Machining is a fascinating subject.
WHAT HAVE YOU MACHINED GUYS?
WHAT WOULD YOU LIKE TO MACHINE?
WHATS THE WORST MACHINING RELATED INJURY YOU'VE EVER SEEN OR SUSTAINED?
WHAT WAS YOUR ALL-TIME FAVORITE PROJECT AND WHY?
DISCUSS, TALK SHIT, SHARE INTERESTING PLANS ETC. ETC. ETC.
and now my real questions...
I might be able to get my hands on a Smithy brand CB-1239 combo mill/lathe/drill press sometime in the next couple of months.
The lathe chuck is seized up really bad(need a hammer to turn the chuck key), where can I find a replacement and how much can I expect to pay for it?
it doesn't have a mill chuck, where can I get one?
the belts that turn the lathe are missing, will automotive V-belts work?
the table doesn't move untill you've turned the handle 22/25 of a full turn is this normal?
if it isn't normal, can it be fixed?
this thing has probably been sitting in the back of a warehouse for the better part of a decade or two, what sort of parts would deteriorate on something like this?
>>952865
>combo
JUST
>>952865
seems like there's a pdf manual. read it. parts connections should be standard (morse tapers/etc.)
>The lathe chuck is seized up really bad(need a hammer to turn the chuck key), where can I find a replacement and how much can I expect to pay for it?
shoot carb cleaner between the jaws and the chuck
take it off with the bolts on the back
you may just have to clean it up
>it doesn't have a mill chuck, where can I get one?
enco or msc or ebay
>the belts that turn the lathe are missing, will automotive V-belts work?
they're probably standard belts. check the manual.
>the table doesn't move untill you've turned the handle 22/25 of a full turn is this normal?
>if it isn't normal, can it be fixed?
is it loose or hard to turn? hard to turn, find the slide lock, unlock it. or the gibs are too tight
loose - broken gears?
>this thing has probably been sitting in the back of a warehouse for the better part of a decade or two, what sort of parts would deteriorate on something like this?
nothing much. will have to clean out lube and relube everything.
>>952865
Take the chuck off the lathe, try cleaning it up.
Soaking in Diesel will usually loosen up the old grease or dried out oil.
The jaws are often numbered to correspond to slots, just reassemble the same way.
If you've pulled the jaws and it's still stiff, find a bit of keystock the same size as the key, chuck it in a drill and while douching it out with penetrating oil, run the drill forward and backward to free it from the dried grease or rust.
A lot of mini lathes use large O rings for drive belts, but if you find a small AG or industrial belt that fits, they should work fine.
I have a belt from a concrete cutoff saw turning my old Atlas.
>>952886
just what?
>>952888
>is it loose or hard to turn? hard to turn, find the slide lock, unlock it. or the gibs are too tight loose - broken gears?
it's really loose for that 22/25ths of a rotation then it becomes really hard to turn but it does turn and with a relatively uniform resistance thereafter.
>gibs
???
>lube lube everywhere
kind of figured
does it hurt you as much as it hurts me that if I don't save it this thing is gonna be left out in the open uncovered near a warm gulf-coastal area?
>>952901
>large O rings for drive belts
the ones on the mill motor look like automotive V-belts
the OP pic is the same model and make of machine, it's not a desk-mount sort of thing...
>>952904
952901 here, I'm just saying that one not need some kind of maker specific drive belt, and that a same sized substitute could prove serviceable.
Just keep mind of the V belt width when sizing for length to keep it from singing.
>>952865
>chuck is stuck
It's just dirty. Take it apart, clean the chips and shit out, grease it, reassemble. Easy peasy.
>combination machine
it's a shitty lathe crowned with a shitty mill, 4/10 would only use in emergency
>belts
yeah probably, but I'd order replacements
>excessive backlash
shitty lathe, cannot be fixed
I know it's tempting to save money by getting a combo, but I've never seen a combination machine that was worth a shit. They prey on the uninformed by selling shitty cheap crap to newbies who don't know better. Lurk craigslist and local industrial surplus places, buy an old south bend lathe and bridgeport mill. Be warned, shit is expensive. basic bitch lathe and basic bitch knee mill will set you back about 8 large including tools. Watch out for 3 phase power requirements.
source, I am a machinist by trade and own my own shop
>>952987
>4/10 would only use in emergency
but would you use it as a machine for learning?
...is $300, or possibly free too much for this thing?
>>952994
Nope. Just rescue it and have fun with it.
Make some chips.
>>952865
>will automotive V-belts work?
my old ass lathe is runnin
audi belts
what up
bought it from a slovenian WV mechanic, so it makes sense
added 45*s on my robot IO plate and removed some excess material tonight, nothing fancy, i just wanted to stay late to check out this finnnne lady that was working nights
everything machinist bro said is bang on, just rip the millhead off.
chuck? take it apart great way to learn
dont worry about backlash either, you arent there yet anyways
>>952987
silencer on the far left
was that one piece or what?
>>953045
>Make some chips.
will do, or else I'll maim myself...suggestions for early projects?
I know a mill or a lathe are both powerful tools of creation, but I need some ideas to copy or try out cause I draw a blank when given too much reign.
eventually I'd like to make fetish equipment, but that is not for here.
>>953052
>my old ass lathe is runnin
>audi belts
awesome.
>>953063
>dont worry about backlash either
>Backlash
THAT WAS THE WORD
I thought it was "whiplash"
>you arent there yet anyways
it'll bug me anyway...I'm used to a CNC router and a Laser. those don't have backlash, and tolerance to .005" and .003" respectively
>>953098
>I'm used to a CNC router and a Laser. those don't have backlash, and tolerance to .005" and .003" respectively
they have at least some backlash, they just hide it well.
With as much money as I've dumped into pic related, I'm not sure I've come out much ahead over just buying something outright.
I KNOW I'd be well behind if my time was worth anything.
But oh well I guess. It's almost done (it's functional and has made a few parts for itself already), which pleases me greatly. Need to re-do the motor/ballscrew mounts (they were never intended to be made out of MDF), add sleeving to the ballscrews, and put on a pump/drain for coolant. Tested it just a little with some mild steel and was very pleased with the results.
Also bought a mini lathe recently. Need to upgrade the headstock bearings on that; it does not perform to my satisfaction even on small steel parts and I hear swapping the stock ones for tapered roller bearings makes a huge difference. I'll eventually convert it to CNC, but that's on the back burner for a while.
Experimenting with grinding fly cutter bits for aluminum. r8 my surface finish. Looks pretty, but I have no idea if it's supposed to do this.
>>952902
Gibs are what keeps the carriage tight as parts wear. You adjust them to keep the play to a minimum while still allowing ease of motion, generally needs to be done every so often depending on use.
>>952865
I understand some of the basics of how a lathe works and can cut and bore, but how do you e.g. make screw threads on things with one?
>>953805
if the lathe has an automatic feed, you can adjust how far the lathe's tool carrier will move per revolution of the work-piece.
is how you make threads
>>953808
aaah
>>952987
>combination machine
>it's a shitty lathe crowned with a shitty mill, 4/10 would only use in emergency
are combo machines really THAT bad?
>>952865
Forgot to take the chuck key out of the lathe abd turned it on at 3k+ rpms to the face. Broke my safety glasses and nose. I thought someone had sucker punched me so I turned to the nearest guy and punched him in the face, climbed on top of him when the shop teacher pulled me off and into the corner to explain I wasn't hit by the other guy but the chuck key. Was sent to the nurse where she gave me an ice pack and sent me back.
>>954366
>the shop teacher
>>954366
>I thought someone had sucker punched me
You really thought someone sucker punched your face from behind? And you just attack the nearest person?
What are you? 16?
>>954373
I had a really cool shop teacher who let us get away with all kinds of stuff.
>kid is making a battle axe and the teacher sees his plans
> he says, "it's not a battle axe, it's a table leg!"
> I'm making a .22 zip pen gun, teacher walks over asking if I'm making a one hitter
> look him in the eye, “Nope, a pen gun"
> we'll call it a spring powered spitball launcher
>>954378
To be honest I thought I had been hit and that was my response. Scared the other guy enough that he stayed away from me the rest of the semester.
>>954380
Did you apologize?
>>954378
I was probably 16 or so, this was around ten years or more.
>>954385
Yes, when I got back in the shop I immediately said sorry.
Im trying to build my own lathe but im wondering if i can usea steel beams for teh bed
>>954390
>steel beams
feel free to use jet fuel around it
>>952987
Your cans, or someone elses?
New to machining. Actually in an adult education class for it right now because work is sending me. Nothing better than taking a raw piece of material and making it into something useful.
>>953098
Lightsabers. Sell them and buy better tools.
>>954390
Concrete and grout.
>>954718
I doubdt i can get a perfect flat surface with concrete, as i recall, you need a flat leveled surface for the carrier and stuff
>>954830
You don't use concrete for the bearing surfaces. You cast steel into the concrete for that.
The problem with concrete is not that you can't get it perfectly flat (you can), it's that that it shifts slightly over time. The thing will only hold tolerance for a relatively short time after it's made. Epoxy granite is a promising alternative that doesn't have this problem and is essentially identical to concrete construction, but is significantly more expensive.
>>954843
Steel casting? Thats way off the possibilities of my backyard, thats why i was thinking of something already made, also, i been told that a small washer engine would suffice as a starting point
>>952865
Just another nobody's opinions
>I might be able to get my hands on a Smithy brand CB-1239 combo mill/lathe/drill press sometime in the next couple of months.
I prefer separate lathe and mill, but if a combo is cheap, it s WAY better than nothing
>The lathe chuck is seized up really bad(need a hammer to turn the chuck key), where can I find a replacement and how much can I expect to pay for it?
you can take it apart to clean it
FIRST, use an engraver to number the jaws clockwise, so you know how they go back in.
>it doesn't have a mill chuck, where can I get one?
you gotta know what kind of spindle it has: R8, MT or whatever. for mill bits you use a collet, for drilling you use a chuck.
>the belts that turn the lathe are missing, will automotive V-belts work?
depends on what kind of pulleys it has... need pictures
>the table doesn't move untill you've turned the handle 22/25 of a full turn is this normal?
>if it isn't normal, can it be fixed?
it's not good but it might be worn, might be misadjusted, either way is probably fixable as long as the screw is good.
>this thing has probably been sitting in the back of a warehouse for the better part of a decade or two, what sort of parts would deteriorate on something like this
rubber parts - seals. not a lot. rust is the main problem, tight-fitting parts tend to fuse togehter....
>>955191
>but if a combo is cheap, it s WAY better than nothing
thats why I'm champing at the bit to demonstrate that the repairs will be more trouble than the machine is worth to the company...because it is...we're a welding shop, nobody here machines.
>you gotta know what kind of spindle it has:
MT3 according to the manual.
>collets
about that...I've seen fluted mill bits that have cutting surfaces on both ends, with flats i the middle...wouldn't that tend to carve out the inside of a collet?
>tight-fitting parts tend to fuse togehter....
I'll watch for that.
apparently the tailstock is also very stuck...
also, the lathe chuck opens to a 2" hole all the way through the machine, it looks like that was the intent, but what benefits does this have for me?
>>955181
Gingery uses a cast aluminium ways with a purchased plate of cold-rolled steel on top.
Scrape ways, scrape steel, screw together, scrape steel again.
>>955204
>thats why I'm champing at the bit to demonstrate that the repairs will be more trouble than the machine is worth to the company...because it is...we're a welding shop, nobody here machines.
it aint worth much. scrap value maybe. big 3-in-1 machines weren't ever popular
>>you gotta know what kind of spindle it has:
>MT3 according to the manual.
>>collets
>about that...I've seen fluted mill bits that have cutting surfaces on both ends, with flats i the middle...wouldn't that tend to carve out the inside of a collet?
No. the double-ended mill bits are usually made stubby, so they will work in any style of holder. it gets grabbed by the center section, no matter what kind of holder you use.
Pic related: MT3 stuff for a mill
----the top image is a plain MT3 collet. this holds one size mill, or a drill bit with the EXACT same size shank.
----the 2nd image is a mill holder on an MT3 arbor. This holder only holds one size of mill bit, and it has the retaining side-screw for the flat cut into the tool bit. If you buy a set of these holders then ALL your mill bits must have that flat for the side-screw to hold them in, or you must grind a flat yourself with a diamond grinding disk. Round-shank mill bits will NOT stay in these, even if you tighten the side-screw hard.
---the 3rd pic is a ER25 chuck on an MT3 arbor. this holds a range of sizes; normally ER chuck sets can hold any diameter of tool from the smallest to the largest size.
any of the above is okay for hobby use. the ER25 is most convenient, but there are considerations (***continued in the next post***)
---the 4th pic is a jacobs-style chuck on an MT3 arbor. good for drilling with but you don't ever use this for milling.
>also, the lathe chuck opens to a 2" hole all the way through the machine,
that is so you can cut on bigger pieces of metal, up to ~2" diameter. it's a good thing.
>>955345
>any of the above is okay for hobby use. the ER25 is most convenient, but there are considerations (***continued in the next post***)
When you are starting out with a hobby mill, mill holders are expensive but you don't really need to be able to hold ANY size of mill bit.
You only really need one size: 3/8".
,,,,for any size of mill bit from 3/8" down to 1/8", you can buy mill bits with a 3/8" shank.
,,,,for making light but broad cuts (to flatten surfaces) you want a "fly cutter", and the smaller cheapo fly cutter sets have a 1/2" shank. So for that you want a 1/2" holder too.
,,,,And then you would want a jacobs chuck too, for drilling.
You could buy a complete MT3 collet set for $60, but some of those sizes you will NEVER use. It's not that good of a deal.
MT collets are $16 each on ebay. A MT3/drill chuck is $20. So $50 + shipping and you're GTG.
If you get that ER25 collet holder set shown instead,,,, it costs more but then you don't really need a drill chuck, because ER collet sets normally cover the entire range from the smallest to the largest collet sizes.
Such as,
if the ER25 collet set has sizes from 2mm to 16mm (every 1mm), then each collet can squeeze down 1mm from whatever size it is. So you can hold any size of shank from 16mm all the way down to 1mm. You could hold any mill bit between 16mm and 1mm shank, and any drill bit within that size also, and it will all work properly.
ER collets are made to hold a (small) range of sizes properly, but other styles of collets like MT or R8 are not.
An MT or R8 collet that is 1/2" size can ONLY hold a tool that has a shank that is *exactly* 1/2". Any larger tool won't fit in, and any smaller tool will wobble no matter how hard you tighten it.
>>955357
Also we note: a big reason you end up with a collection of tool holders for a smaller mill is because of the vertical space limitations.
Different tool holders are different heights,,,, sometimes when working on a tall part, you don't have room for the one you would normally use (pic related)
Spindle collets leave the most vertical room--but they also only grab one single size of tool.
>>952865
>tfw never had acess to tools and knowledge related to machining and welding but always died to do that
>tfw apartment with no space
>tfw little money and classes 24/7
Fuck my life. The only "hackerspace" in 1000km is a 5x5 room filled with homos and hipster from the architect course that only know how to work with arduinos and get wet over some flimsy over priced drone.
>>955345
>data data data...
YES
>>955357
>And then you would want a jacobs chuck too, for drilling.
I actually have a drill-press at home...granted it's twice my age and a little worky...
>An MT or R8 collet that is 1/2" size can ONLY hold a tool that has a shank that is *exactly* 1/2". Any larger tool won't fit in, and any smaller tool will wobble no matter how hard you tighten it.
I'd have thought some engineer would have worked out some system for correcting that...
>>955368
>vertical space
with this setup thats less of a problem, the milling head swivels all the way round and raises really high to clear the lathe.
>>955406
my suggestion?
move some place with a modest industrial work. the city I grew up in makes a majority of it's money courtesy of oil refineries. this means that everyone and their brother comes tool-equipped for something. it also means that more people are also selling tools and stuff secondhand.
I grew up with access to SMAW and oxy-acetaline welders and a full(or nearly full) wood-shop. almost all of this was secondhand tools bought for cheaps.
>>955345
also
>perfectly smooth cones
what stops these things from simply falling out of the mill?
>Milling grips for an old gun
>Have brilliant idea to mill the top and bottom face, drill holes, then screw it down to a block in order to do all the outer edge at once
>After breaking several bits opt for an aluminum block instead of cold-rolled steel
>Pic related once it got to milling, just ripped the fucking threads out
Pretty cool how the threads were still on the bolt, probably just going to put it directly in the jaws, just wanted to avoid it at first because it will require half a dozen setups
>>955703
A lot of pressure evenly applied
>>955212
In the beggining i was thinking of a gingery style lathe but i kept being told that, its great as a learning experience but not so good for some serious machining, so i thought that i could follow those plans and prints, and replace some parts for another material, like those "T" shape steel beams or some square tubing filled with concrete for added weight and torsion resistance
>>955703
You see the opening on the narrow end of the taper. That is for what is known as a draw bar. It pulls that taper into the taper in the machine thusly making sure it doesn't fall out and stays perfectly central. Its amazing stuff truly.
>>955795
Rule of thumb. For maximum thread strength drill and tap 1 and 1/2 the depth of the width of the thread. So for 1/4-20, go down 3/8ths.
For 3/8th's go down 9/16 So on and so forth.
Also, helicoils are your friends with aluminum in high strength situations.
>>955701
>I'd have thought some engineer would have worked out some system for correcting that...
well they did.
The ER collets (and other more-modern types) contract at both ends when squeezed.
Earlier collet styles like MT and R8 only contract at one end.
>955368
>vertical space
>with this setup thats less of a problem, the milling head swivels all the way round and raises really high to clear the lathe.
yea, but when milling or drilling with the mill you can still run out of vertical room... in particular, when you are using a larger + longer drill bit and want to drill a deep hole in something.
>955703
>perfectly smooth cones
>what stops these things from simply falling out of the mill?
the mill spindle has a drawbar--a long screw that comes down from the top of the spindle and threads into a threaded hole in the rear end of the collet.
what keeps jacobs chucks on a JT arbor is,,,,, Stephen Hawking's pimp hand, biotch.
You just make sure both are clean, tap it a couple times with a hammer and it stays on as long as you only drill with it. Many people (like me) even wipe it with a bit of oil when it falls off, to help prevent rusting--and it still sticks on and stays on for a few months. This is why you don't mill with a drill chuck, because side-loads will cause the chuck to fall off.
You can find one-piece and screw-on jacobs chucks & arbors if you want. You still can't mill with them tho, as the mill bits will tend to creep downwards out of the chuck jaws. Drill chucks aren't made for side-cutting, at all.
LOCKING TAPERS AND DRAW BARS
also
weldon holder a shit
dont get a weldon shank holder
Did someone say Machining?
>>956158
Currently working on this, finishing up the taper tomorrow maybe. Will post progress.
>>956159
1.) how do you get the smooth taper?
2.) how are you going to put on the carriage mounting arms?
Any machinebros have any advice on turning up some soft face hammers?
Need a few, mainly brass face, UHMWPE and a dome faced version of each.
>>956222
>how are you going to put on the carriage mounting arms?
from the drawing, it looks like a press fit cross drilled through the barrel. note this is not authentic in any way to the civil war era.
The modern drill bit was actually a byproduct of the civil war. Prior to that star drills were pounded day and night to ream a gun barrel, which often led to metal fatigue, and devastating malfunction on the battlefield.
for a replica, the plan doesn't look bad, just don't call it authentic.
>>956310
neat...now the real question.
do you think it could fire safely?
>>956313
Did the plan come with instructions for use, or was it just decorative?
I can't morally, ethically, or legally answer your question, but I have made plenty of small canons that use 3/4"I.D. (.760) Seamless Mechanical Tubing, for the barrel, and fire 12 gauge shotgun shells.
>>956322
Heavy Wall Seamless Mechanical Tubing is available in all sizes.
Check with an attorney in your state for any legal questions.
>>956325
>those walls
What schedule is that? How the hell do you join those?
>>956326
with very deep bevels, and a lot of passes...
>>956326
https://www.youtube.com/watch?v=KMT97bqaOdM
>>956222
I'm going to mill a block to mount this onto, that's what the pin is for. There's another page with instructions on the block.
>how do I taper
It's manual/ CnC
I can program the taper in like so and even set a program to automatically repeat taper cuts for me until the end diameter is 1/2
>>956319
Oh lordy, I couldn't do this without auto feed. Manually setting up for a taper isn't that hard but it's a pain in the butt.
>>956322
>can it fire?
I doubt it, its made to be decoration. Not that it would blow up or anything since it's CR steel mounted onto a steel block I will soon mill with a Brass/ Steel pin. If I wanted to make it fire I would have to drill an ignition hole half way up the barrel.
>TL;Dr
Maybe, but I wasn't designed to fire. Its decoration.
>>956942
My current progress is turning the barrel down to 7/8 to begin the taper. I work on it for an hour and a half Monday - Friday so progress is slow but steady
>>952865
There's a guy on u tube reworking a combo lathe search that you will find it interesting and useful. BUY THAT COMBO!!!
>>952865
>WHAT HAVE YOU MACHINED GUYS?
I machined a lineup punch with a replaceable hardened steel end about 14 years ago in highschool metal shop.
I'm hoping when we move and I start my new job I'll be able to get a shop built at our new house so I can get a lathe and a mill and get back into it.
>WHATS THE WORST MACHINING RELATED INJURY YOU'VE EVER SEEN OR SUSTAINED?
Once saw a guy get two of his fingers et by a lathe. Apparently he was lucky it wasn't worse.
Without starting a new thread this looked like the best place to acks.
So, I collecect, refurbish, and generally love old microphones. I just got a beautiful 1940s astatic mic for like $15 - it's worth around $130 refurbed. Worth even more to me as an awesome project and collectible.
Most of my refurbs involve repairing/replacing the electronics and not more than brushing and polishing by hand... however, this is obviously going to take some machine work.
I have a bench grinder and I bought a brass wheel and a buffing wheel with a few different polishing compounds. My plan is to remove all the old rotted paint and corrosion with the brass wheel, and then polish to a sheen with the buffing wheels. Am I doing this right? I've done a good amount of google dot comming and youtubing on the subject and this is what I've decided to do, although some people say I should do a chemical paint strip instead. Which seems messy as dick. The mic is steel (possibly stainless) so it should be able to handle the brass wheel fine, I think.
>tl;dr: clean & polish metal wat do general
>>956942
>I would have to drill an ignition hole
Not necessarily: given how small the thing is, you could probably use touch explosive to do the igniting, and set it off by giving it a tap.
>>957561
inb4 someone whines about ruining the "patina".
>>955181
No, not actually pouring molten iron into the concrete/granite. I mean you put your rough steel parts into the concrete form/mold before pouring the concrete into it.
Then you machine and scrape them as necessary before assembly.
>>957568
kek, i know right. this thing is beyond patina. anyone who considered that to be patina probablu considers barnacles on a ship and fire damage in a house to be patina
>>957571
btw pic is closer to what it's sposta look like, although i have some different idears
>>955703
Steel has a fairly high coefficient of friction.
And there's a SHITTON of force on those mating faces.
Assuming just 20lb/ft on a 16TPI thread, there's over 24,000lbf pushing the collet into the holder. Accounting for the angle of the taper adds another ~10:1 advantage, for an absurd 240,000lbf distributed across the mating face of the collet.
With non-ideal materials, that probably drops to well under half of that, but you can still easily see why that thing ain't goin' nowhere despite not having any positive locking mechanism on it.
>>955795
>>Pic related once it got to milling, just ripped the fucking threads out
How the fuck? Aluminum obviously is nowhere near as strong as mild steel, but the force required to tear out a screw thread (unless it's a very small screw and/or has very few threads of engagement) should be far higher than force necessary to mill the thing...
>>957571
God guy you gave me a boner.
Tho, the metal casing isn't steel. It's some aluminium X aloy. I've seen a lot of it on stuff made before the 60s.
It was greate, but is now super britle.Most screw threads will be unsuable after you take them out, so get some tappers ready. The drit and the dus till come off after a wash with acetone, and a few runs on a soft buffing wheel. Just take it slowly, since said material is by now really easy to scretch on the surface witch will amke it look ugly. If you take it slow it will be all nice and shiny
>>957601
thanks for the info friend! so i don't want to use acetone if i can help it (it's a long story but using shit like that in my dad's workshop isn't going to fly over well). how bout i use the tripoli compound stick with the buffing wheel? that should get the paint and rustshit off without harming the Al too much yeah? also please look at my most recent photo of refurb'd beauties... missing a few recent ones but oh well
>>957606
The acetone is to get the top layer of dirt off. Its mostly grease and shit from the air around it, you could use WD40 and a dry rag to do the same cleanup if your dad is some sort of all natural no chemicals in my shop machinist hipster, but acetone is a dirt cheap method.
Do thins before the polish to get a better result
A "friend of mine" machined a 1911 and an ar15 lower. Both turned out very well if "he" doesn't say so "himself"
>>957613
cool beans! i will probably do that then. thanks again for the tips
>>957569
Oh i see, ill check that out, but i kept reserching..aka searching in jewtube, and theres a guy that made his lathe with motorcycle parts....and ive got plenty of parts laying around, so i might try that desing
>>952865
Don't have pics on me right now but have some burr I made the other day that turned out a pretty purple
>>955795
10-24 thread, and I think I went a bit too aggressive for the feed on the milling (Not too aggressive for the bit, just too aggressive for the thread)
>>957614
Come on man you don't have to be like that, if you're American then machining your own gun shit is 100% legal as long as you follow GCA/NFA (SBR/SBS/Machineguns) and don't make it for the purpose of sale
I'm doing a project for uni (mechanical engineerin). I have to design a part that has a square through hole in it. The side of the square is around 30 mm (that's just ballpark, it's up to me really). There is going to be an end of a lever inserted into the hole; it's cyllindrical in shape and the axis of the cylinder is perpendicular to the axis of the hole. Due to the nature of this linkage, i need all four of the inside faces of the hole to be machined to some reasonable precision and surface finish. I believe it's easiest to roughly cast this thing first and then machine the surfaces that need it.
How would machining something like this work in real life? Is casting+machining a reasonable way to manufacture it? I want to design it in such a way that it would be realistic to manufacture.
>>958095
If you're a mechanical engineering student then come back when you have a CAD drawing (or at the very least a shitty hand sketch).
>>955701
>my suggestion?
move some place with a modest industrial work. the city I grew up in makes a majority of it's money courtesy of oil refineries. this means that everyone and their brother comes tool-equipped for something. it also means that more people are also selling tools and stuff secondhand.
I'm currently stuck here doing a Electrical engineering course. I'm at the beggining of it. The plan is to move out and buy a piece of land in the caucasus or the US once I have enough money to sustain myself for some time.
>>952994
It's ok for learning, I guess. for $300 go for it.
>>953063
none of those are my cans
>>953805
two ways. If your lathe is equipped with power feed and a half-nut you do this: http://www.mini-lathe.com/Mini_lathe/Features/features_2.htm#Half_nut
If not, you can still die-cut threads. Die cut threads aren't as accurate or neat as single-point threads.
Of course, if you're talking about inside (ID) threads, you'll use a tap in a floating holder held in your tailstock.
>>954336
yes. The only thing a combo machine saves you is one set of carriages. A lathe will have a carriage to move in the X and Z directions, a mill will have a slide for X and Y. A combo machine uses the same piece of steel for both functions, otherwise it has all the same parts as a lathe and a mill. For the privilege of this tiny savings, your mill head is perched atop your lathe in a manner that is terrible for rigidity, which is crucial for good quality milling. I would honestly buy a 7x12 lathe and a Taig or Sherline mini-mill for hobby machining on the cheap.
>>958112
My bad, here is the drawing. The part in question is #3, or rather the far right end of it.
>>956943
do you even make chips bro?
>>958549
isn't that feed a little deep?
>>953622
That's fucking dope. I've wanted one of those since forever. Finish looks sick idk what it means either lol
>>958549
3,5mm depth and 0.3mm/rev feed.
she could handle it, but it was just in her comfort zone
>>957990
>touching the shavings
I food that once, and cut my hand really bad. Never Again.
>>959050
>food
Did. What the fuck, swype?
I have £12,500-15,000 to spend on a 4-axis vertical cnc mill. What do I buy?
>>959050
>pick up metal shavings
>ouch sliver
>can't get out
>feel metal shaving splinter in finger for weeks
>MFW it makes it's way through the pad of my finger and out underneath my fingernail
I'm with you anon.
>>959646
>>959050
one of my friends got a metal sliver right in the vein in pic related and when he was fucking with it he pushed it in and the tip of it traveled up to about his elbow and a bruise started forming. had to go to the ER and get it removed. ever since then i've been more afraid of the world.
>>959648
zozzle, forgot pic
Anyone made their own CNC and made money making stuff with the CNC?
So I'm looking to get a part done. It's stupid simple, just facing operation and drilling on a 1 x 1.5 x 0.5 inch block, but it's steel.
Every company I talk to just wants to partner with companies and doesn't want to help a diy gook like me.
Any idea what kind of person or company would be willing to do that in the states, and how much a company would expect to charge me?
>>961169
Forgot pic
Ignore seemingly random lengths. They are standard sizes in inches.
>>961169
>how much a company would expect to charge me?
more than you buying a block off ebay, buying a drill press from harbor freight, and drill bits
For anyone that works/worked in a shop:
Could a guy ask to come in and learn from you guys a few days a week?
I'm an engineering student soon to graduate. I had a bit of machining experience (lathes and milling mostly), but loved the fuk out of it, and want to keep learning about it. I noticed my interest in it is making me a better engineer too - when we get asked a design type question in class, most people don't consider what it's like to actually make a part in the shop and what will make it harder/cost more to do so.
>>958171
Drill then broach.
If you are looking for persision better than 5 thousandths broach a little under sized and file to size.
I broach about 15 parts during week and i achieve 2-3 thousandths repeatability.
>>961169
How many do you need? As long as we're not talking 2+ hours of machine time I'd take a crack at it for more practice, hell we probably have plenty of scrap stock to do it out of here
>>961182
Best bet would probably be to find a smaller shop (<50 employees) that has CNC machines that aren't in heavy use, and try and work out a deal with them to rent time/expertise.
Hell, at our shop if someone wanted a deal like that we'd probably just have them running our CNC setups to pay for it, 2 birds with 1 stone
Also, are you looking for a job? And if so where do you live/are willing to live? We're in major need of another person to handle engineering roles and it's hard as fuck finding people who want to learn and be good at what they do
Pic unrelated, most recent side project to machine a new firing pin plunger for an old pistol
I sometimes forget how strong my dremel skills are
>>961219
Literally just one.
I can tap it myself if needbe, and if you're serious I could pay you. I don't have like 200 to spend on this, but I'll happily pay you 40 or 50.
>>961231
And the tolerances are pretty much arbitrary. if you can punch a hole with a 3/8" drill bit, a 3 mm drill bit and a 6mm drill bit, that's good enough, or at least good enough for me to clean it up and tap it myself.
>>953622
What are those things your wires go through called?
>>961244
Cable carriers?
>>961231
Yeah that's doable, shoot me an e-mail at [email protected]
>>961244
Cable chain, cable carrier, and drag chain are what I've usually heard it called.
They're also obnoxiously expensive for what's basically some cheapass injection molded plastic, but what can you do?
>>961296
Buy 'em from china?
http://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20160314072720&SearchText=wire+carrier
>>961182
Depending on how busy my shop is, my boss might entertain the idea and maybe even let you do some of the work yourself.
>>956942
Prototrack Brother! We have a SLX lathe at work. two MX2's, and and EMX converted mills and a SMX 3 axis bed mill.
So god damn easy to learn how to use.
And speaking of working on a barrel.
This is the final operation I did on the barrel for my 10/22.
I cut it down, threaded it, recrowned it, cut a dovetail in it for a front sight and made a muzzle brake (thread protector mainly).
The threading operation. Adjustable 3 jaws are an awesome thing.
>>961175
Look for small job shops. The one I work at would do that. As for charging, I can't say as I am just a handle turner and the boss would be the one to decide that but probably around 50-100 bucks.
>>958095
You need to learn to Broach . This can get expensive . But you can hold tolerances using this method . Real tight dimensioning and you will need to make the part with 2 pieces . Bolting one part to the other .
>>961182
I run a boring bar . The shop charges $108.00 per hour . those tolerances get your price way outta range for you .
>>961169
I run a boring bar . The shop charges $108.00 per hour . those tolerances get your price way outta range for you .
>>961185
>It needs to be done by cnc
Nigga any hackjob machinist could manage 0.002" as long as the machine itself can.
A retarded capuchin could do it with a DRO.
I'd do it myself for him if my machine wasn't out of commission for an indeterminate amount of time.
>>963593
it's probably going to bug you when I tell you that lots of engineering coursework (apparently in lots of places or so it's been insisted at me by my professors) tends to condemn blood-and-meat machinists as woefully inaccurate and inconsistent and not fit for work down past .001" unless it's absolutely the only or last option.
the textbook for my elements of manufacturing processes class said that for anything finer that CNC is the only way...other textbooks on the same subject say similar...
...let you rage flow through the interwebs...
I also work with welders who have apparently been using a small end-mill as a drill press for several years and think 1.) a couple of locking grip pliers is enough to hold pieces in place, and 2.) that there's nothing wrong at all with drilling through pieces and into "that fancy moving drill vice"(the milling table) "the shavings are a different color, I can tell when I'm through my stuff"
>>954385
yes but it was awkward
>very nervous try to say "are you okay" and "im fucking sorry" at the same time
>say "are you fucking sorry"
>the kid cries
>>954378
Why would anyone have a shop teacher if they were over 16?
>>963913
Because some of us took four years of shop in high school.
>>963799
As a welder, a machinist, a CNC operator, and an engineering student, I am disgusted. There is so much wrong with that paragraph.
Please tell those individuals to pack sand up their ass with a jackhammer.
Currently working on a mastercam program for a gear replacement part for a manual lathe
Just milled a gozillion threads in hardox 500 (50+ HRC).
God, have mercy on those poor souls who decided it was a good idea...
>>965910
as one, uninitiated in the machining skill...what part of the process was difficult and why?
>>965912
It is wear resistant steel. Five times harder the usual mild steel. I couldn't find a combination of spindle speed and feed for a pair inserts to last more than 10 holes...
What does this mean:
ALL SHERLINE MILLS...(See Figure 2.) To check the built-in error of the machine use a dial indicator mounted in the spindle. Move the table under spindle with the Y-axis handwheel and note the error. This error will usually be around .001" to .002" (.05mm) in 3" (76mm). (Remember the components are not precision ground, they are precision milled.) When squaring the head this error should be accounted for. Remember you are squaring the head and spindle to the base of the machine where the saddle travels, not the surface of the table itself.
Why would you square to the machine base and not the surface of the table?
>>965912
As >>966341 said, Hardox is semi-exotic alloy of steel that's particularly hard and wear resistant. The harder and stronger something is, the more difficult it is to machine and the faster it will wear down your cutting tools.
There isn't much that's worse to machine than that stuff that you would actually try and machine. Off the top of my head, I can only think of chromium-molybdenum ("chromoly", pretty common material for bearing balls), which is an outright nightmare for anything but grinding.
>>966595
I've Heard bad things about beryllium bronze and titanium, more of the same problems?
>>966600
Beryllium bronze is somewhat toxic, and if you actually get what it can give you, it's a chronic effect. It's only really a problem if you're making dust with it, though, and I don't really know how you'd do that without grinding it. Which, in turn, also wouldn't make much sense, since it doesn't grind well at all. In any event, most workplaces will mandate special precautions when working with it, which are inconvenient. Other than that, it's quite machinable.
Titanium's just really tough. It's not all that bad, considering the kinds of superalloys that are out there, but it's more problematic than most typical steels.
>>954366
>autisim hurts
>>966600
The fella above has it right, Beryllium itself is nasty stuff but outside of nuke stuff it's almost always around 2% of a copper alloy. Dust particles that enter your body (lungs) remain there; your body is able to breakdown the copper over time leaving the beryllium. As with asbestos concentration is the key, it's longterm exposure that gets you.
It should be machined wet, as even if you're making nice chips (it does machine well), along with those chips is dust. I machine probably less than a pound of it per year and keep it wet, I'm a cautious person and I'm not worried.
Titanium can be bitchy. Really sharp tools and good chip evacuation are necessary. It work hardens in the blink of an eye, drilling is tricky, step drilling is a no-no, and tapping is really a bear. Specialized taps are really worth it. Since it's so strong you can go oversize on the tap drill as long as you can get that approved by the client.
Repair of water impulsor
>>961238
>And the tolerances are pretty much arbitrary
Never, ever, ever fucking do this
every time i see a print like that i want to strangle the incompetent shithead who made it
if you slap a needlessly tight tolerance on all your dimensions "just to be safe" you deserve everything bad that happens to you
tolerance any critical dimensions to where you need them and use ISO 2768 for the rest
IT grades are fine too, if you want to be weird about
"TOLERANCES UNLESS OTHERWISE SPECIFIED: ISO 2768-m"
that one sentence will make your (and the machinists') life so much simpler
>>958095
You'd use a horizontal shaper, which you'll find in any machine shop in the 1970s.
>>968535
Is there a chart like this for US units as well?
So machining general, I present a challenge
How would you reduce the diameter of this chunk of metal by just over 0.1", without using a lathe?
I ask because while I do work in a machine shop, our lathe is busted (Used to just not be concentric, now it doesn't even turn on) and it's been a very low priority because we practically never have a use for it. And the only machine shop in the area that does lathework is going to cost upwards of $200, so fuck that
>>969048
Chuck part in mill spindle, tool in vise (or bolt your lathe toolpost to the mill table). Now your mill is a lathe. I've done this several times for weird jobs.
>>969053
That sounds just crazy enough to work
And hell, we've got a manual and CNC mill (I should probably stick with the manual one though the CNC gives me terrible ideas)
>>969053
>>969059
Scratch that, turns out our manual mill has too much play in the Z axis to be able to do this kind of shit. Boss said he'll go ahead and see if he can get our electrician out here to look at the lathe since apparently it just doesn't get control power, though the lack of concentricy worries me, my tolerances are loose enough that it will probably be fine
God knows when our electrician would be by, so I'm still open to other ideas
>>969053
>Chuck part in mill spindle, tool in vise (or bolt your lathe toolpost to the mill table). Now your mill is a lathe.
I've done this for small & short parts, more than a couple times.
I've even been meaning to get a couple of mini lathe chucks (a 3-jaw scroll & 4-jaw) and put them on a straight shank so I can use them just in the mill for these silly tricks... Another thing I've not yet gotten around to doing.
>>969071
>hough the lack of concentricy worries me
k while this shit is spinning in the chuck, give it a smack until it runs true
or use a surf grinder and a whirly-jig
>>969048
Is that a Sten bolt?
>>969163
>a surf grinder and a whirly-jig
I have a sudden desire to know what those things are...
and before you tell me to google them, their names are ambiguous enough that google gives me less than trustworthy data...
>>969166
lol i googled it quick before posting to make sure it was a thing,
whirly-jig is a like a rotary table, but for grinding, so its accurate as shit but not as rigid as a milling machine one, i dont even know the real name
punch former? radial tangent dresser?
whirly jig grinding is what i googled,
thats what we call it at work
and surface grinder
Currently working on a project for myself. Here's a pic on how awesome is this mill from 1940.
Held together with wire.
>>958645
Most carbide tools are under used. You are using it just fine.
I remember that when i was a noob at machining i was scared to work that fast.
Now i crank up the lathe as much as it can.
>>969071
Are the bearings shot or are you using a crappy 3 jaw? If not the bearings and the 3 jaw has too much runout you can shim with shim stock or cigarette paper to get it true.
Or if you have one (I am always amazed not everyone does) a 4 jaw will get you dead nuts.
>>968535
I once had someone ask me to machine him a part to 0.00001"
I told him to pack sand
>>969644
why not take his money? it's not like he can actually check that.
Don't know enough about lathes to guess what the actual problem is, but I can say this
It's a 3-jaw, big sucker too
And apparently there was an incident involving the lathe and an overhead crane and that's why it's off center, so my guess is it's not going to be a wear and tear issue
>>969644
>I told him to pack sand
Why do that when you could just give a quote for 100x what you'd normally would do it for?
Turned some motor shaft adapters out of aluminum on a cnc lathe and mill the other day.
Was my first time ever machining anything and now i want a lathe and mill of my own.
>>969942
I still remember the first time I ever did a proper machining operation.
>TFW
This is getting stupid, hopefully I can stop harassing /mg/ about my lathe problems, but I'm still trying to think up how to do >>969048 with what I've got
>Need to remove about 0.12 inches of steel from the diameter, our lathe is apparently .050 off center on top of not running, plus I'll have a hard time getting my workpiece in the jaws due to the size
>Boss said if I needed less taken off I could just chuck it up and hold a piece of sandpaper on it while it spins until it's the right size
>There's only 1 place around here that does lathework, and they'd charge and arm and a leg for this
>Looking more and more at a benchtop precision lathe, just not ready to drop the money needed for one I don't even have space for
>Wondering if I should just slap something together like this: http://www.instructables.com/id/Mini-Metal-Lathe-1/
>Don't want this project to drag around with no progress for ANOTHER year
>>952865
Oh, I miss CNCs...
>>952987
Another machinistfag by profession.
This man speaks the absolute truth. I came to this thread to say exactly this.
>>970353
how do i become machinist
>>952865
Worst injury i saw was a guy get a 4 inch open end wrench straight through his chest. He left it on the the edge off a massive fucking die press and it came down hit it the perfect way and it shot across the room and nailed him.
Before he died he said look what ive done to myself and dropped
What is a good accurate not crazy expensive caliper option,
>>970435
Starrett
>>970416
>Worst injury i saw was a guy get a 4 inch open end wrench straight through his chest.
>Before he died he said look what ive done to myself and dropped
>>970442
reminds me of the bug in AOE2 that if you save a game as "staret" when you go to load it, it will instantly cause a defeat.
>>970416
Well no one is going to top that...
>>970481
I've heard horrible stories from work, but haven't seen any.
Falling off utility pole wrong and getting a 4' long piece of wood through your torso.
Not working around power right and getting fried by 20kv going through the guy and his bucket.
Using a winch wrong and frying the whole truck by connecting it to high voltage when the cable snapped.
...
But the most important thing in our weekly safety meeting has been sorting trash properly, for months.
>>970416
>shit getting launched and ruining someone's day
The thing here.
Someone left one on top of an anchor plate on a vertical CNC. CNC was running at ~3k RPMs digging through a chunk of steel.
One of these vibrated off the anchor plate, fell onto the end mill, and got launched into a guys shin. Shattered it so bad they cyborged him with metal plates.
>>971232
I do machine work for my design team at Uni. It was 9 at night, and I needed to get this joystick mount done on the mill, and it was a lot of stopping, locking up the spindle, changing tool, starting, going, stopping repeat.
Bottom line is I fucked up, grabbed the spanner, go to lock up the spindle, and accidentally turn the machine on.
Darn thing would have broken my arm if I went the other way, but instead it got thrown across the shop, bounced off the pneumatic press and nearly killed a guy on the lathe, who shot me a "what the fuck are you doing here" look.
I finished the part and left and haven't been back since.
>>971410
If I had a dollar for every guy I've seen launch vice grips or a wrench or a chuck key, I'd be very well off.
These are measurements in thou of a tooling plate I'm making. My goal was to remove the extreme ramp the table had in the x axis, which I have done, but now the y axis reads this. Would you leave it alone or cut it again?
>>971575
>Would you leave it alone or cut it again?
If you're that guy who has to square that thing multiple times per job, I'd stick with my previous suggestion of "throw it in a shredder".
And, if, for some reason, you still insist on keeping it, I'd say that's probably about as good as you're going to get on that thing. If it's fuckin' up that badly, going again isn't going to help matters.
>>971582
Not him, I'm the other guy complaining about this shit machine.
All will be well soon though, I have ordered an unadjustable fixed column that comes square from the factory. I will use that to make a flying buttress support for the flimsy z axis.
Eventually I need to find some way to replace the head entirely because even that rotates relative to the z and is held in alignment by friction only.
are these any better than those combos with the milling head mounted by the chuck?
>>971746
To be fair, bridgeports are only held in place by friction. But its also 5/8th's bolts. Sure they have screws on them for moving the parts, but they have a couple degrees slop in those parts.
Really the difference comes from the weight of the parts and the fact that they don't use cheap shitty hardware.
New Drills.
>>971746
>held in alignment by friction only.
That's normal. Any mill that has tilt/nod adjustment is just being clamped there by the bolts. Doesn't matter if it's "just friction" when there's 10-tons+ holding them together. Granted, you won't be seeing that much on a machine that small, but it won't be experiencing anywhere near the cutting forces, either.
It's merely a question of "how well was it made", really.
>>961169
>>961175
>>961169
>>961175
Putting that tight of a general tolerance is just stupid. There's no way that every dimension needs to be that tight. Tolerance the tight ones, and blow the general tolerance out to +/- .15mm
Anyway, Rapidcut will machine this for you, for like 50-100 bucks with very fast lead time. This assumes that you relax your tolerances to normal ranges.
>>963824
I didn't come here for these feels.
>>969644
I have parts that are toleranced that tight, they're gauge rings that are used to calibrate inspection tools.
They get cut out on a lathe, cylindrically ground, and then coated (electroless nickel). Then they get lapped to final dimension.
My inspection department doesn't have the equipment to check this, so we just take the vendor at their word. But yeah, that guy sounds like an incompetent idiot. So many engineers these days are just stupid kids that are being pushed through college my the thousands. It's absurd the amount of money they waste with tolerances like that.
>>970416
>>970481
>>970472
I work in maintenance
we just had a fatality with a guy I work/worked with. investigations are still ongoing because it just happened yesterday.
>the guy and I were working close but not on the same line of machines
>we shoot the shit about machining and he tells me he just got a new small lathe for watch making and about how much he loved it.
>we go back to doing our jobs and about an hour later...
>heard the other line turn on and incoherent screaming
>I already knew what happened
>walked over knowing what to expect, but seeing it on 4chan and in real life are 2 different things.
>Just red everywhere
>top of the guy's head sticking out was the only thing I could see, but it was so quiet a pin drop could have probably been heard.
>blood and gore dripping on the ground and the strong smell of blood and gastric juices penetrated my nostrils.
>imagine 2 steamrollers eating you feet first, very slowly, so you felt and knew every little thing that was happening to you as it crushed every bone and blood vessel as flat as a piece of thin cardboard.
>female operator saw the entire thing
>she had to be taken to the psych ward because she had a psychotic break screaming "turn it off!" repeatedly 15-20 minutes after there was nothing that could be done.
Guy left behind a wife, a 4 year old, and a 1 month old. He always talked about his family with a smile on his face.
Lock out tag out properly, guys.
oh and to be on topic does anyone have any drawings for a standard tool holder for a lathe? I don't want to have to spend 50-80 dollars for one on msc, and what steel are they usually made from?
>>972018
It might be time to rethink your career choice.
>standard tool holder
There's no such thing, what size tools are you working with, quick change tool post etc.
>>972028
>It might be time to rethink your career choice.
yeah, I've always looked at this job as a stepping stone to something I've always wanted to do.
>There's no such thing, what size tools are you working with, quick change tool post etc.
fuck, I was a afraid of that, I guess I'll have to pull one off the lathe, dimension, and copy cat one I already have.
>>972018
This is what lock out tags are for. Unfortunately they get disregarded in some work environments. I know guys who have walked off jobs for simple harmless lockout infractions- this is why they are alive.
On a similar note, when I was a pup I scrubbed down fishing boats evenings after school for cash. The super cool old dude at the ice house was gone for like a week, he had been there rain or shine for 40 years or something (the ice house had this monster hose that would blow ice into the goliath coolers on the boats).
He was clearing a bockage in the auger when the owner's son hit the switch. This was deep South no lockouts like 1900 tech. But everyone knew to yell for an all clear before power. It's always the fucking owner's son/nephew/some other knucklehead family member who does this dumb shit.
Guy came back a couple weeks later with his right sleeve pinned to his shoulder. The lunatic kept working there.
>>972217
>Failed to do so properly
Shiiit.
You shouldn't have to use a $100 cut proof lock. You should be able to use a zip tie and everyone should respect it, but we know people are pieces of shit.
>>972018
Same thing happened at the finish/sampling building across the parking lot from my job.
Guy was cleaning a sampling press for a plastic injection mold. Had it locked out.
Some fuck head took the lock off (I have no idea) and switched the machine on.
They had to squeegee him off the wall/floor of the machine. I was forklifting some finished molds back to the truck bay, heard the most inhuman sound. Guessed what had happened.
I took the next day off. Couldn't stop hearing it.
>>972245
Not the other guy.
I bought my own lock. Only other guys who have keys are the superintendent and the foreman.
>>972282
did the guy who took off the other guy's lock go to jail? because we're told that's a criminal offense if we do it.
>>972283
we're given locks from day 1 and told to keep them safe and within eye sight at all times.
>>972245
his lock wasn't taken off or cut, he was locked out but not correctly. (I deleted my previous post explaining this but I felt I went too indepth of details.)
>>972087
why on earth does someone ever turn on something they're not using?
clearly if you go to use a machine you should ask around why its switched off at the breaker?
>>972283
>someone else has a key to my lock
this is bad practice. everyone should have their own locks with no other keyholders. the reasons for this should be blindingly obvious. bolt cutters will get them off but try explaining to a judge why you cut off a lockout lock and killed someone.
especially you should never trust a faggot with an interest in avoiding LOTO proceedures like a foreman or plant manager. they get billed for every hour of downtime. there are things called performance bonuses. at minesites for example, managers get paid a fixed sum. then any hour of downtime is fined from them. they will fuck with safety proceedures just because every hour down costs them thousands of dollars. they can expect some downtime. but they are going to want to minimize this.
lookup how often electricians get crushed by machinery they're working on because no LOTO
>>972288
well it's clearly murder 1. its not like a lock saying, "removing this will kill me", thinking about it, removing the lock and flipping the breaker can ever be considered an accident.
On a lighter, more unrelated note, the robots for a new system arrived, and the little one is kawaii as fuck
>>971749
Not really, its pretty much the same thing.
Although, the 'mill' part would have a greater travel in its X axis.
The vertical colum for the mill is held in place by a single bolt, so any heavy cutting or crashes will require you to re-align it.
Also the table on that lathe doesn't look like it has a convenient way to mount a small vise to.
If you have a very specific idea of what you want to make, and that machine is capable, it probably will survive you will, but its far below the versatility of having a real mill as a separate unit. (Even if its a smaller one)
I'd imagine the lathe part is just fine, same as a normal lathe that size/import quality without the mill adaption.
>>972713
oh my fuck that is so adorable its like a scaled down large one, not the usual small style
is that an EXP1250?
What is the best way to store little drill bits?
I have a bunch I've bought separately over time, because decent-quality sets of small drills are farkin expensive... Some places sent them in a little plastic case, but others just send them in a paper envelope or plastic bag. The envelopes and bags take up too much toolbox room and are a bother to search through.
I had to order a few more and I am having raging autism attacks over how to store the things.
I couldn't find anywhere that sells GOOD cases for tiny bits. I need a way that I can mark the size of the drills on the case, because most are too small to have markings directly on them.
I could buy a $2 set of cheap Chinese crap drills and throw away the drills, but the cases aren't real good either. I need to be able to mark the sizes of the drills correctly. Like 2mm, 2.05mm, 2.1mm, 2.25mm, ect....
Just now I found some place on aliexpress selling mechanical pencil lead cheap that came in longer tubes, so I bought a bunch of tubes of pencil lead, (yes, you know it's coming),,, Imma throwing out the lead and just keeping the tubes. They wanted like $2.25 for ten tubes of lead, and the lead is 12cm long. I can mark sizes on the tubes.
I'd like some way to store them that is easy to get to any one, but that won't dump them all out if it gets tipped over.
Sticking them in a sponge/in a box would work, but you can't mark sizes on a sponge....
You can mark sizes on a piece of white rubber, silicone or urethane,,,, but machine oils tend to destroy rubber, silicone and urethane....
sigh
I can't think of any way that seems like it's gonna work well. :P
>>973352
I assume you have a good drill press at least.
Take a wooden block long enough for the drills and slice it so that you know have two pieces. Draw a grid pattern on the top and bottom pieces, and drill a small hole on the bottom just big enough for the drill bit. Drill a larger one up opposite of it so that you can put the blocks back together. Leave enough room to mark what drill goes where and you should have a nice drill block. If you want to keep it all together, get some hook style latches and you can use those to keep it together in case of falls.
>>972947
Yep, and I may get to learn how to program them this time around too, so I can't wait until I have one flailing around doing stupid shit in the name of practice
>>973352
Look for a "drill index", you might be able to find empty ones to buy
But if you mean storing multiple bits of the same size, you can rig up a rack like so I guess
First time on a surface grinder. Launched a chunk of hex stock at my lip could have lost teeth or broken face bones. Got lucky with just the lip split. 10 stitches and it was deep enough to split that little web behind my top lip. I'm still warming up to the grinder again.
>>969053
That is so fucking ghetto.
I love it.
>>971841
They're drill *bits* you fucking double nigger.
>>973594
No, those are drills. The thing with a table and a handle is a drill press. The thing you hold in your hand is a drill motor. The thing you hold at the top and rotate the middle is a brace. And in a brace goes a bit. Bit and brace.
The actual cutting tool is a drill, simple as that.
>>973614
Bit and brace refers to the drill(bit) as you refer to it and brace being the mechanical drive.
https://en.m.wikipedia.org/wiki/Drill_bit
>>971841
>New Drills.
how much did they cost? HSS? cobalt? $$$-carbide-$$$?
I know where to get good sets, but they cost a lot of money. Like, $300 for HSS and $450 for cobalts
I took the usual route of buying a crappy $80 set and just replacing the individual bits as needed.
Some people say "don't buy shit" but this does make financial sense because many of them you never use anyway. The common fractions and the common tap drill sizes get used a lot, and most others stay totally clean.
>>973365
>Look for a "drill index", you might be able to find empty ones to buy
I need one for tiny bits and can't find any like that.
pic related: there is only 3 kinds of mini drill bit cases on aliexpress:
#1--case design is okay but bulky... it can be marked on because it's yellow tho (these drill bits are shit, only good for wood & plastic)
#2--the case design sucks (half the space wasted) plus it's black (can't be marked on) plus only room for 1 or 2 of each size. (drill bits are also shit)
#3--only works for small + short drill bits. (drills are carbide, so they are brittle--but at least it's real carbide)
#4--is the cheap-ass version of #3, since it is just the inside part.
I may make something like #1, since I like it best.
>>973775
Hertel 135 degree split point HSS oxide coated. $370 normal, I got it for $270 on sale after tax.
It has everything from #1-60, A-Z and 1/16th to 1/2th by 64ths.
I work in a job shop and since we never know what is coming around the corner having everything is worth while for me.
>>973807
hertels are nice
i'm a hobbyist so i wait for 20-25% off + free shipping from enco to stock up on cheap stuff. i guess msc/enco are starting to completely merge, i'm getting emails from both and msc boxes from enco.
>>973817
Hertel is MSC's offshoot now. used to be owned by Kennametal but was recently bought off.
I got my drills on a 35% off sale offer my boss got. We have a deal. I bought the set, he maintains it since it is only being used at his shop.
The big thing is the point geometry is ideal for us. Those split point's don't walk and cut very nicely.
>>971841
My university shop has that exact set
>>961175
That M6x1 hole shows a flat bottom and threads to the absolute bottom.
That would be difficult to do, and would require thread milling on a CNC, or an old-school machinist to hand modify a tap.
I suspect you will want to allow drilling deeper than the necessary thread length.
Those 9.53mm dia holes are a touch over 3/8". this is probably some sort of slide.
You want to spec those holes to be reamed. that process can hold very tight diameters.
people don't want to deal with you because you don't know what you are doing, and will be a pita, unless somebody wants to take pity on you.
But, you have got to start somewhere.
Oh and jesus fucking christ, if you are a fucking American, and are designing parts in inches (which you are), don't be a fucking douche and dimension in metric. And if you are designing in inches, don't use metric fucking threads unless you absolutely must.
This drawing screams amateur on about every fucking level.
Yeah, mechanical engineer that owns a machine shop.
Don't feel too bad, we all have to start somewhere.
>>968535
>>968963
I've run hundreds of thousands of dollars of parts though machine shops (maybe millions at this point - all one off), and never dealt with this.
BUT every single feature on every drawing I create is dimensioned, with a tolerance (usually the global one on the sheet).
This reliance on a standard is a very European thing (I know of it, but don't use it).
My drawing sheets end up very American style, with notes to the machinist. I'll do a design review with the shop foreman, and maybe the machinist before releasing the drawings for fabrication.
I think that as an engineer it is my responsibility to think a design all the way through fabrication, including the machining setups necessary. If a machinist chooses another approach, as long as he hits the tolerances, I'm fine with it. I have always felt the usage of these style tolerance guidelines are a cop-out for the engineer; and results in just throwing drawings over the wall to a machinist to just figure out, and do the best they can.
I try to design for the processes, people, and even machinery they have when doing the design. Normally I am personally responsible for the success or failure of a given project. There is no 'team'
Anyway, I don't like that fucking table.
>>976211
About on point.
I do a lot with 3D printing, where I can just plug in whatever shape I want and say "Go" and it's done.
The problem I ran into with the dimensions is that the components that slide into the two holes are all a standard 3/8", but the standard threads that go into the top and bottom are M6x1, so no matter what units I used, something looked messed up and I had to round. Is there a standard format for different units I'm not aware of?
>>977692
>The problem I ran into with the dimensions is that the components that slide into the two holes are all a standard 3/8", but the standard threads that go into the top and bottom are M6x1, so no matter what units I used, something looked messed up and I had to round. Is there a standard format for different units I'm not aware of?
I'm not sure that I understand what you are saying, but you can easily override each dimension's units on a case-by-case basis. So if the part is is going to be machined from inch CR1018 bar stock to inch sizes, with 3/8" holes, just dimension everything in inches. If say you have one value whose native units are mm, you could add that dimension as mm with a note elsewhere on the drawing that all units are in inches, except where noted.
But given that the part is basically all inches, all the machinist is going to do the moment he sees your drawing is do that conversion with his trusty calculator and write it on the print. Normally I would suggest make the dude's life easier and keep that single unit in inches.
I design in both unit systems; the choice depends on the problem definition, and customer. That fits my engineering training. If the problem is specified in SI, do it in SI. If in feet/pounds/slugs do the calculations in the native units.
For mechanical design, if the design is for the US military or for overseas, the design is SI. If for the US market, mfg with US material, use US units.
One thing I noted about your design is that you really over-specified machining operations. Because machine work is so expensive, you want to limit every single operation that you can. If the raw bar stock comes out with a +/-0.02" width tolerance and a .008" thickness tolearance, and you can live with the bulk dimensions, just bump the tolerance on the relevant sizes up to the sock tolerances. If you need a single face dressed, just specify that and drop the major dimensions enough for a finish/skim cut.
>>977767
>>977692
Because you have such tight tolerances on the outer dimensions, your poor machinist is going to probably going to start with 2"x3/4" bar stock then machine every single face while cursing your name, and the shop owner will easily charge you $80/hr.
Normally you only want to have a single dimension shown once in your drawings. You dimension the isometric view, but these are superfluous. This just clutters your drawing, and adds zero information.
Really the isometric view adds nothing (or very, very little), and you should add a view of the other side with the M3 tapped hole. Drawing every face with machining operations is a good idea. In this case it would just help you get a part back with 2 tapped holes instead of one on a single face. If you at least should have added a (2 Plcs) to clarify without the other view.
You have not paid attention to datums. You dimension what is relevant. I suspect the distance between the 3/8" holes is what is critical. The dimension should be between those two holes, with the tapped hole between them dimensioned either from the block edge datum (preferred) or one of the holes.
When the part goes to QC, they are going to try to measure exactly every single dimension you have drawn from exactly every datum you show. You really screwed the pooch on that one. Your datum choices are all over the place.
Shop drawings are a language in and of themselves. I used to think they were a stupid complication between CAD and making chips, but I no longer think so. I take pride in dropping a bundle of drawings off at the shop, and the machinists love to point out when I screw up and forget a dimension. They always get the DXF files for waterjet, etc too - no sense redrawing geometry on the machine.
>>977692
I know you're using Inventor, so setup a dual dimension style that you can apply for individual dimensions
Also, center lines are your friends when it comes to holes, it's an easy way to let fabricators know at a glance whether a hole is meant to be on center or not
Granted none of these were a problem on my end, because my CNC programming suite works directly in Inventor, so I simply don't need drawings for it, just the part file itself.
If I were sitting at the CNC punching this in though, it'd be a totally different story.
>>977770
Hey, that's pretty much exactly what I did. In all fairness, I've never machined steel before so I didn't realize how agonizingly slow it was until I sat down to do it. Round 2 is going to just be with 1.5"x1" bar stock though, the guy said cold-rolled tolerances should be just fine for this application so all I'll need before the holes is a cleanup pass on the saw cut ends
any of you have mini mills and / or lathes? Are they worth it or better to save up and get a normal sized one?
>>978077
Get a normal sized
>>979219
Where from and how much should i be spending? Want to be able to do aluminum at least.
>>979907
how much space do you have? get the biggest machine tools that will fit
![480.4959[1].jpg](https://i.imgur.com/jBpDbTE.jpg "480.4959[1].jpg")
>>978077
I have pic related, but upgraded with a quick change tool post and 4" 4-jaw chuck (standard is a 3" 3-jaw).
I like it, but the size is both its major strength and its major weakness.
For one, I have no place left in my garage to fit any more tools. Between two workbenches (soon to be a third one that has to fold out of the way), a CNC router, all the other stuff that's stored there, and the fact that the car has to still fit, a full-size lathe simply is not an option in my case. Thus, I'm happy that it exists at all because, otherwise, I'd simply have to go without.
The size also keeps cost down; new, including the accessories and tooling, I only paid a little over $800 for it. You'd be lucky to find an old, barely-usable small-ish lathe for under $1000.
But, of course, the small size greatly limits the size of your workpiece. Despite being a "7x14" machine, around 2" stock is the absolute maximum you can comfortably work with (this is generally true of all the mini lathes). Larger and you're likely going to have to come up with some odd workholding solutions, and finangle with the compound to get the tool in position for your cuts.
There's also the consequence of a small machine not being as rigid as a large one, limiting the rate of your work. It's fine up to aluminum, but steel is kinda slow going to avoid chatter issues. I've read in my case that upgrading the spindle bearings to tapered rollers from the stock deep groove radial bearings is actually most of the issue with that, not so much rigidity. Haven't done it yet (most of my work is in plastic), but it's a cheap upgrade at $13-ish for two wheel bearings.
If you've got the room and money, a proper lathe is definitely the way to go. The niche for the small machines is really people like me who simply can't work one into their shop and budget.
As an aside, if it doesn't come with a quick-change post, get one immediately. They're not expensive and the lantern toolposts suck to use.
>>976211
thread milling a M6x1 is nearly imposible.
The drawing may be simplyfied.
Threading to the bottom is made with a finish tap.
It comes with other two taps in a kit.
>>981805
>thread milling a M6x1 is nearly imposible.
This kind of false, even M2 is doable
>>981805
>M6x1 impossible
>not thread-milling .5mm x .1mm
