Alright /k/
so I was reading an issue of Firearms News when i came upon an article titled "Pour A 100% complete AR Lower", and basically this company called ar15mold is selling these kits for you to mold an ar15 lower out of a polymer resin. It requires no mechanical skill and the most basic kit comes with enough resin for 5 lowers (the author of the article said you can easily get 6 out of it with some leftovers) and this mold with a bunch of small pieces to form the holes and make the lower to the correct dimensions. They also have these mettle brackets that you put in the rear of the receiver to withstand the constant recoil of the rifle. Price on their sight is about $340 for the most basic option. If you do get 6 receivers out of this, that would mean each one costs you about 56 dollars and you can still use the mold to make as many as you want.
Would you buy this/ should i buy this? watched a couple of vids and the lowers seem pretty solid. the polymer is made to flex under extreme weights and stress to keep it from breaking, so they aren't "flimsy".
>>30349528
i saw this kit posted here on /k/ a few months ago. really neat concept. i want to be able to buy enough for one lower, not 6. at that price, its too much for an untested novelty item.
>>30349528
Sounds like I just figured out the new family game for Christmas.
>>30349552
i get where you're coming from. How many lowers do you need exactly?
>>30349552
well consider this. when flat screen televisions came out. they were thousands of dollars however; because the people who could afford it bought them, they were able to lower the price of these flat screens. Who knows, if they become a well known company then maybe they'll go down a bit
Why do I feel the extreme need to get a rainbow polymer lower for an AR?
Yeah, sure, it's expensive.
But after you make six lowers, you can make unlimited AR jello shots. The fun doesn't have to stop.
>>30349528
What does this cost? It's not like 6 lowers are going to exactly be cheap no matter how you get/make them. You can pick up some Andersons for $50/each on sale, I doubt this kit is more than $300 + 6 transfer fees.
>>30350198
$340 that makes six. about 56 per
That resin is fuckin expensive. I would consider this if I could get the mold without resin and find something else that works
>>30350321
you can get just the mold on their sight
>ar15mold.com
>>30350268
So then take your pic. You can get make some shitty polymer lowers or you can buy some aluminum ones for about the same cost. I think 80% lowers cost about the same too, if you already have a drill.
>>30350042
>well consider this. when flat screen televisions came out. they were thousands of dollars however; because the people who could afford it bought them, they were able to lower the price of these flat screens.
That's not why TVs are cheap, cunt
>>30350398
these have support braces, so not as shitty as other polymer options
When will they make an aluminum casting version? I want to make my next scary salt riffle out of soda cans.
>>30350143
> /k/ finally can make custom-poured poly lowers to match their custom-poured dragon dildos
mfw
>>30349528
My dude you don't even need a kit. Some guy on arfcom made a mold from a stripped lower by putting it in a box (made of fucking Legos) and filling it with silicone sealant; could even be used for a lost wax aluminum casting if one were so inclined. Can't hunt for the link on mobile but it's out there if you search.
>>30349528
Anyone else find the ingenuity around building AR lowers heartwarming?
No matter how hard those who want absolute control try, freedom-loving Americans will find a way to be free.
The future may bring hard trials, but hope is alive.
>>30349528
I wouldn't trust it dude, there's no control on the orientation of the fibers, it's likely that there are a lot of places for flaws (microcracks) since your pretty much just pouring it in a mold.
>>30352002
I want to build a forge in my backyard for this very reason
![scruffy_second[1].jpg](https://i.imgur.com/r7s6CSS.jpg "scruffy_second[1].jpg")
>>30349568
>>30352002
1. someone already tried and they're shit
2. soda cans aren't 7075
3. soda cans are shit
>>30352059
that's cool and all but how does it save your threading and pin holes properly
>>30352100
>there's no control on the orientation of the fibers
There are no fibers
It's essentially just injection molded plastic which is all you need
They come with support braces for the rear section
>>30349528
>>30352059
Yeah I'm wondering how do few people here know seem to kmow about that. I'm a newfag and not be be a shill but I've mentioned twice this week
http://www.ar15.com/forums/t_3_4/676733_Fruity_Ghost___DIY_100s_of_ARs_cheaper__faster__gentler_.html
Tried it myself with an 80% but didn't have a proper container and ran out of silicon and had to squeeze the sides, fucked it up lol will try again soon
>>30352353
>also, I assume these are easy to paint since polymer?
anything is easy to paint
>>30352359
are you the ARFcunt poster?
why go through the hassle of making it yourself when you can buy them already made for less with a lifetime warranty to boot?
>>30352002
Look into casting. People have been casting objects for over 6,000 years. Yes six thousand. If some fucking goombahs in rhobes could do it before the discovery of electricity surely you can do it in your back yard or garage.
It's ridiculously easy to make guns with modern tech. The two things that are a challenge are the barrels because threading but even that's not too bad, really the springs is what will get you if making from raw materials. Springs are fucking magical. People grossly underestimate spring technology.
>>30352415
because that requires an FFL transfer which is between $20 and $100 depending where you live?
>>30352380
No don't have an account there but I lurk, actually not even, just bump into when looking stuff up
>>30352415
>hurr i can't understand why anyone would want an untraceable AR
>>30352415
surely this typa response 2 these things qualifies as archaic by now, surely in 2016
>>30352423
>$20-$100 FFL transfer fee
1. go to LGS
2. "gimme dat polymer lower"
3. "that'll be about $50 +tax, sir"
4. give them money and fill out 4473
5. don't be a criminal
6. ???
7. profit
all my local stores stock a few plastic lowers and if not they have them to order at their website
if they're charging you extra money for an FFL transfer for their own product they're ripping you off
>>30349528
>All those hard edges
Common nig, make it rounded so it doesn't snag when I insert it into my asshole.
>>30352480
>filling out a 4437
this is why you're not gonna have any guns when it's time to use them.
>>30349708
bout treefiddy
>>30352480
I've never ever ever seen a polymer lower sold in a gun store
And I've been to a lot of fucking gun stores
>>30352480
>every gun store has polymer lowers
>missing the fucking point of 80%s
>>30352532
To tell your grandkids you made it yourself :)
>>30352480
>>30352523
And yeah I've never seen lowers either
>>30350321
Also take a look at Fields Metal.
It shouldnt melt the mold, and its metal rather than plastic. Assuming the reciever doesnt get hot, it should hold much longer and harder than polymer.
I would want to dremel some custom rollmark on that mold... do you thing some company would 3D print/ laser it in for me for a cleaner cut?
>mfw special snowflake at last
>>30352480
>don't be a criminal
You mean:
>be a good boy and turn your guns in when the time comes because only a criminal would want to buy guns via private sale or manufacture them from as few finished parts as possible
>>30350042
the thing is, you can do this with silicone, an existing lower, and plastic bought separately for far FAR less than $350.
this is expensive because the company is trying to make a buck off of stupid people.
>>30352314
>that's cool and all but how does it save your threading and pin holes properly
by being a perfect cast around them?
>>30352002
you need a forge for that and knowledge of how to do lost wax casting for that, which is a bit more complex and a lot more dangerous for the common pleb than pouring plastic.
These would be good for putting some serial numbers on then taking them to a buyback or for when gun confiscation ever does come hand them these. They are firearms by the ATF definition after all.
>>30352523
>>30352570
>never seen one in store
i guess it's a Texas thing
a few of the shops i frequent stock in state built .308 lowers too
>>30350321
>>30352684
Yeah again, $30 silicone, can't remember resin, used a 80% for test will do real lower soon. Got my Elmer glue looking lower for under $50 I think +reusable mold
![234-015A_DetailEnlarge[1].jpg](https://i.imgur.com/tKwiSnw.jpg "234-015A_DetailEnlarge[1].jpg")
>>30352634
>Fields Metal
Starts to melt at 144 F. My car gets hotter than that during the summer. No thanks.
>>30352066
Indeed it does.
If the lowers are strong, I'd consider it.
This is going to be a dumb question but do you need to fill or submit any forms for making these lowers?
>>30352793
The answer is no.
Unless you do something dumb and accidentally a pinhole directly above the safety selector hole, about 3/8" up
>>30352742
You're going to fuck that, right?
>>30352423
tfw I can pick up anderson lowers at aimsurplus for $43 out the door. no ffl fee when picked up at their store.
>>30352812
3rd hole isn't the only difference...
I'm an ausfag
if I bought this I would probably go to gaol.
I am probably on a watchlist right now for looking at this thread.
>>30352812
Well shit.
Does this vary by state? Can you give me a rundown on how making you own lower works legally?
In CO for example we have universal background checks required for all sales, effectively banning private sales. Could myself and 5 other friends go in on one of these kits, then each of us pour/construct our own lowers? I'm just trying to stay legal.
Any word on how strong these are?
Are they comparable to these hybrid lowers:
https://www.youtube.com/watch?v=Zyzzcd3wYFE
>>30352877
No, but that's the main one they buttfuck you for.
Unless you have other shit you plan on doing.
>>30352890
Nigga. What you're buying is the equivalent of a specialty ice cube tray.
Is THAT illegal in your state?
Wait, I just realized you can literally use this to make a lower made of ice
>>30352911
I think you mean a lower made from pykrete.
>>30352890
Idk about co but it's usually leslegal to construct firearms for yourself as long as the gun is legal (no full atuo, short barrel etc) and your not planning to sell it. I guess each person would have to mix and pour their own
Also this isn't the official but some other guy who's molding and casing, trying diff resins. Can't remember what mine was. Something cheap from Amazon
https://m.youtube.com/watch?v=MSDovg_d5v4
>>30352911
Chocolate
>>30352940
I wonder if you could make a candycane lower
>>30352925
Anything, really.
>>30352890
Look, BUYING a gun changes all over, but general rules include being 18 for long guns and 21 for pistols, passing a background check, and whatever hoops your state mandates.
MAKING one....just don't make an NFA item without first informing (and getting the consent of) the ATF, or have intent to sell once built.
If you and some buddies went in on it, none of you bought a firearm. You all bought this cool mold and some liquid that hardens after some time. Legally, this is a huge difference.
>>30352940
This man gets it.
>>30349528
It's a neat concept, but for $340 you could easily have both an upper and lower receiver of reputable quality rather than 6 complete gambles.
>>30352933
Yeah that makes sense. As long as each individual is actually making their own lower and no one is selling any completed lowers to anyone.
I'm honestly very interested, just concerned about the quality and durability of the end product.
>>30352978
Well if you look close at my pics I beefed it up quite a bit, you can research different resins, add fiber glass or aluminum strips, I'm sure you'll be able to make something tougher than some low end poly lowers. Mine feels pretty solid, I really need to try again and assemble
Maybe the /pol/ is getting to me but this feels like a shill thread.
http://www.youtube.com/watch?v=D3Asb6Ou6ds&t=16m27s
These lowers seem weak.
>>30353241
https://www.youtube.com/watch?v=D3Asb6Ou6ds&t=18m32s
They're fucking flammable. Underdeveloped product. Won't be buying.
>>30353262
Holy fuck, this thing isn't even suitable as a fucking range toy.
>>30353262
>what guns? i lost them all in a tragic campfire accident
>>30353241
>>30353262
>>30353295
Lmao! I'll watch full vid tomorrow, I don't see mine (white one^) doing that, idk what plastic they're using
If you do it right you can make really strong cast plasitc, they gotta make a profit but if you buy good resin and fiberglass or whatever you can get something pretty though
>>30350397
I'm not seeing it. Only the kit which includes resin already. The rest are spare parts for kit
>>30353262
so they're charging out the ass and it isn't even suitable resin
>>30353788
Consider this
>1.buy kit
>2.makes lowers
>3. Bring lowers to local gun buyback program
>4.get $50-$100 bucks per lower
>5. Repeat steps 2-4
>6. Profit?
>>30350143
Now if only ARs could use Bakelite mags...
>>30349708
>need
>>30350176
>AR jello shots
Why hasn't this been a thing.
Also, op, buyinf stripped lowers in bulk you can get pretty low. I ordered 6 Anderson lowers from Classic arms for $39 apiece. $20 shipping, then FFL was $20 for the 1st, then $10 for each consecutive serial.
$54 a lower, shipped and transfered.
That being said, these would raise no ATF flags and you coils make as many as you want in whatever colors you want. Could be fun. Not for me though
>>30355517
Holy shit.
>>30355517
Wait, would they accept these?
>>30352793
>do you need to fill or submit any forms for making these lowers?
as long as you do not transfer the complete lowers, no. If you transfer them, then they need to be serialized, don't know if they need to be registered.
>>30353295
>>30353305
>>30353350
Yeah the resin they're supplying is obviously crap and not strong enough.
I'd consider the kit if it were simply stronger.
It really is a shame they're not stronger, because otherwise it is a great idea. I was wary of non-aluminum lowers but the hybrid lowers from Tennessee Arms look quite strong.
Also I'm not sure how this slipped through but this kit is way overpriced. They're $340 for 5 lowers, or about $70 per lower...
>>30356152
it is technically "the gun"
>>30355517
Buybacks are anonymous, right? Are there any limits per day?
>>30356530
Yeah just checked mines flammable, but I KNOW I bought cheap resin, think $15 and I think I have half left. I have tnarms lowers on the way and think they're injection molded as opposed to cast? Idk maybe I'll do a flame text. Also I might be able to seal mine somehow
>>30350198
Do you have to pay transfer fees for these? I think they'd fall into the same category as 80% lowers
>>30352702
And how do you seperate the mold when you have a 2 inch piece sticking into your front take down pin hole
>>30352237
>>30352870
Lucky bastard
AIM has good prices if shipping weren't a thing
>>30350321
Would bondo work?
>>30355531
>Bakelite AR lower
Did some testing, stress fractures appeared almost immediately. Also saw a video in which it didn't hold the parts together correctly and when the bolt came forward it tore the feed lips off the magazine
In short, unreliable and shitty
>>30352870
where in sw ohio do you live? i also go to aim quiet often.
eastgate area here
>>30352002
>>30352118
>>30352420
>>30352728
Linking all you anons so you can all see this.
>>30352293
>someone already tried and they're shit
If it's the guy I'm thinking of he did it in sand and fucked up the cast completely, it wasn't the aluminum's fault he has butter hands.
7075 has zinc for a primary alloy metal, so I guess it's a little bit like the opposite of zamak but not really. There's like 2% magnesium and I think 1% copper, and the zinc content is something like 5% but base 7075 is basically no better than straight aluminum. What you want is 7075-T7 which is tempered by overaging. I don't remember the precise temperature values or for how long off the top of my head, and my connection is potatoes.
Beercanium is going to have some impurities if you're an amateur, but if you know your shit you'll be able to get it more pure than not and cutting in the alloy metals will help because you need to add flux during that stage anyway. Either way getting close to 7075 and then tempering it (tempering any aluminum is going to help) will get you a nice chunk of metal. You would be better off tempering a billet of knockoff 7075-T7 and then machining it but I guess tempering a finished cast would work fine too.
>>30358253
Buncha beer cans+couple of pennies
After casting throw in oven next time you cook
???
Profit
>polymer AR lower
>>30358850
You'll need a fuckload of cans and pennies are not solid copper, you would be better off getting some junk copper pipe and cleaning it. Magnesium can be found in a fuckload of sources, right along with zinc.
Just be sure to keep the percentages good, alloying is not an exact process because of oxidation and so on. Rarely will you find something with a precise amount, it's going to be a range of percentages. Maybe cutting in some zamak (die cast cars, etc) and then casting a small bar, anneal it, temper it, and then test it. Don't put it into your oven with food, that's a bad idea.
>>30358924
There's nothing wrong with polymers, anyone who tells you otherwise is retarded. Metals just do all the jobs individual polymers do with equal proficiency, which is why it's just easier to use them for most applications. (some metals, just like polymers they're not all made equal)
>>30359163
I'm just saying, I know the whole schtick of these is that they're ghost guns and all, but I just bought a stripped aluminum lower for $43 off SG. I'd rather have metal than polymer if it came down to it.
Also, pennies are hardly made out of any copper anymore. If they were, they'd be far more valuable for their metal than one cent.
>>30359163
What about using screen doors?
>>30352754
This is going to be on CSI as a melting gun, mark my words.
>>30359244
>I'm just saying, I know the whole schtick of these is that they're ghost guns and all, but I just bought a stripped aluminum lower for $43 off SG. I'd rather have metal than polymer if it came down to it.
I truly don't have a preference, quality is quality and either way I'm going to get the same performance out of it. I can easily work with both, but I'm not a huge fan of casting which means I mostly have metal stuff.
>Also, pennies are hardly made out of any copper anymore. If they were, they'd be far more valuable for their metal than one cent.
That's why I said get some junk copper pipe which is solid copper.
>>30359335
>What about using screen doors?
Depends on what alloy they use but sure, that could work. Personally when I'm casting a billet of anything I tend to be very selective of what goes into it, using scrap alloy is not something I like doing without running a test batch. Ultimately you will need to cast a tiny amount (or use the casting waste) and then temper it and test it like I said, just so you know the performance you're getting. 500MPa tensile strength is what you should be aiming for, that's near commercial 7075-T7.
>>30359163
the problem is that the buffer tube is nearly unsupported, even on molded fiberglass it is pretty weak compared to aluminum.
Would buy it if they beef up that bit and actually ship it out with decent resins but from the looks of it it is just going to be a meme novelty that they probably patented.
>>30353241
>Hop eees
REEEEEEE
>>30358253
What about an aluminum bronze receiver?
Polish it up well, slap on some well finished wood furniture and you could probably sell that for a pretty penny to autists like me.
Would JB Weld work?
>>30359504
That'll be wasted on a 5.56 gun, modify the mold for an AR10 and we'll be cooking with fire.
>>30359431
Yeah I'm not so sure about straight resin being the best option here, I think cutting in polymer fibers would be a better choice. but there's no way to compress it in the mold as it cures.
>>30359504
>What about an aluminum bronze receiver?
I mean if you want to but you could do the exact same shit with annealing at a far, far lower price. Aluminum bronze is amazing in highly corrosive environments but beyond that it's not particularly amazing in any way. It's just bronze/brass that's lighter and won't drop zinc or corrode.
>>30359590
I was just throwing out whatever bronze alloy that is strong that came to mind.
Also after googleing someone made a copper plated one and it looks amazing.
>>30359163
Pennies made after a certain point in 1982 (denoted by a slight design change that takes a trained eye to spot, just stick to 1983 and newer) are about 99.9% zinc with an electroplated copper surface, while pre-1982 pennies are about 95% copper (5% tin and zinc), meaning that if you pay attention to date you could use them as viable sources of both metals.
>>30361706
Again, it would be easier and economical to use copper pipe and a direct source of zinc rather than sifting through a pile of pennies looking at the dates.
Pennies are a stupid source of raw materials for anything.
>>30361811
True, scrap copper is everywhere and zinc is cheap as shit. Of course, these would be preferable; I just meant that pennies could be used in a pinch.
>>30359163
No I know, pennies are mostly zinc, with 2.5% cu which you said is the primary allowing agent, can't remember bit it takes a couple dozen cans for a pound of aluminum, like half burns off as vinyl and half remains is slag. I have mild metal melting experience. Also the guy who cast that white lower above
>>30352742
What kind of silicone did you use? that cast looks like it came from a crummy mold.
>>30362323
>I just meant that pennies could be used in a pinch.
Right, but I'm just wondering what pinch would require you to resort to a gallon jug of pennies.
>>30362325
>No I know, pennies are mostly zinc, with 2.5% cu which you said is the primary allowing agent
I said zinc is the primary alloy metal, copper is absurdly small in this equation. Zinc is fairly common in consumer goods, it's not really hard to find but if you two really want to use pennies then sure, go ahead. Zinc is still zinc.
>can't remember bit it takes a couple dozen cans for a pound of aluminum, like half burns off as vinyl and half remains is slag
You need to compress them down tightly, the amount of dross is usually minimal if you keep it tight. Starting with a billet and then adding the crushed cans after wastes less because it doesn't oxidize and burn, but this can all be avoided if you just melt them in a reducing environment anyway.
>>30362390
oomoo 30. like i said it really did, I miscalculated my container volume not making it "snug" enough and ran out, so i threw RR spikes in and squeezed to fill it lol...but also I built up the lower with (sulfur free) clay to bulk it up. but yeah the mag well is distorted
>>30362535
but I thought a buch was already oxidised, oxide surface area on basically sheet aluminum= not much "pure"? I'd use comp heat sinks, and maybe some quarters. sounds like a quality alloy right thur
>>30362942
>but I thought a buch was already oxidised
I'm having trouble following your post.
>oxide surface area on basically sheet aluminum= not much "pure"
All aluminum exposed to oxygen develops an oxidized film, you can see this when you polish it. When you have a thin piece under heat in an oxygenated environment that layer runs deeper, in the case of aluminum cans it's pretty bad. Minimal surface area is the best way to avoid this, you will inevitably lose some aluminum but the difference is milligrams versus grams.
>I'd use comp heat sinks
This would work but,
>maybe some quarters. sounds like a quality alloy right thur
This is just pissing away money, it's a dumb idea. Pennies are one thing, but the value of a quarter is greater than it's base metals.
>>30363225
I meant aluminum cans are extruded or spun or whatever, and therefore already have a layer of oxidation, on top of thin walls meaning you'd only be getting appreciable amounts from the top and bottom. Also idk i figured the nickel of the cuprunickel might help some but if not yeah wires or pipes. also this isn't even something I'd plan to do. Maybeee an AlBronze for looks but id still have to machine some holes and probably threads
>>30362875
>oomoo 30
pleb tier. Pony up for a platinum cure silicone, and don't cheap out. If you make a good platinum silicone mold, it'll last decades.
Take a page from how hobbyists do it, and make the mold in parts, with indexing keys to keep alignment.
With a softer rubber, you'll probably need internal supports in the rubber to keep the magwell and fcg cavity from flopping around like a limp dick - k'nex and legos are great for that. If you're clever about masking and internal support, you could probably do a two-part mold out of shore 15 or 20 rubber - one part for the internal cavity, the other for the exterior shape, and use the stretch of the rubber to demold it.
Else, you can try a three-part mold for left and right halves and the internal cavity using a firmer rubber, shore 30 to 40.
Remember you're making compromises in each case. Firmer rubber is more dimensionally stable, but needs more parts to demold without tearing the rubber, which means more flashing and more potential for misalignment between parts. Softer rubber is less dimensionally stable, but less parts means less flash and less misalignment.
We need a /diy/-/k/ party one of these days.
>>30359644
Oh god that's sexy
>>30357962
That really is a shame. Otherwise it would be a fantastic product. Imagine, you and some friends could all go in about $60 bucks, and a couple hours and beers later everyone has their own lower!
>>30358924
https://www.youtube.com/watch?v=_9XTToSSF6o
I would totally buy the kit if the lowers it produced were as strong as the Tennessee Arms Hybrid lowers.
>>30359553
Wouldn't flow right. Probably would be too brittle.
>>30352415
or, OR, pay $10 more for an anderson lower and not worry about it snapping in half
>>30350176
I like how you think Sir.
>>30363483
Problem is, for starters, any two part resin that you can cast at home is going to be shit compared to the kinds of polymers they can use at an industrial level.
Second problem is that nobody thinks to use any kind of reinforcement in these. The weakest areas are the pin holes at the rear, beaver tail, and the buffer tube.
Chopped Fiberglass or kevlar strand and a metal insert would go a long way in turning these ~300 round before they break DIY receivers into 30,000 round receivers.
Will they ever be as strong as forged aluminum? No.
Will you be able to beat fascists to death with them like you can with your nugget? No.
But it's entirely possible to DIY cast a receiver that's comparable to a commercial polymer one.
>>30363332
Yeah no, you don't want to start cutting in different metals unless you're developing a specific alloy and in that case you might want to step back and examine the metallurgical properties of everything first.
Nickel would most likely be a good addition but it increases hydrogen solubility which means it gases when melting and hydrogen suspends in solution without proper flux. Anything with nickel has a raised pouring temperature but unfortunately this means it picks up hydrogen even easier. Oxidization occurs rapidly which is why most nickel alloys are superheated in a reducing atmosphere and fluxed to drive out all oxygen and cast in an inert atmosphere to drive off hydrogen to prevent any pickup.
>>30352885
We're watching you cuz your such a threat and all on 4chan.
>>30363623
Thanks, didn't know all that. I've seen on the internet though where people make their own crucible steel out of thermite and added carbon, they put it in two nested flowerpots, with a nickel inbetween blocking the hole, long enough for the reaction to take place, then it melts into the rest of the allow, usually into another crucible (silicon) nested in perlite or vermiculite pic related, ripped from here
http://www.swordforum.com/forums/showthread.php?53491-thermite-steel-jthe-joys-of-pyrophilia
>>30363351
also thanks for tip, did have a (cardboard) center support lol. I'm messing with melting milk jugs together for hdpe billets for uses like that
>>30362390
You mean cummy ;)
>>30349528
If I could get a Nylon 6 or 10 polymer and some CF pulp to mix into a single polymer and inject into the mould then I'd be interested in buying a single mould without any polymer.
>>30364162
Problem is, Nylon 6 melts at about 520 degrees fahrenheit. You'd need a metal mold to handle that temperature for starters, and probably something to pull vacuum to get a good cast too.
>>30359556
I'd love to do AR10 molds for upper and lower for beer-can magic, but I also wish I just had a damp mill and lathe so I can just make my own rifle from scratch just by ordering the stock billet and hammer forged components.
>>30359644
Looks like about $6000 lol
Fucking gorgeous ass on it though... Dat grain son
>>30362535
WHY WOULD YOU NEED THAT MUCH ZINC ANON? Christ on a cracker are you churning these out like Russian AKs in '48?!
>>30364287
Shit. Well, back to the lab guys.
Seriously though, I wouldn't be opposed to that. Would aluminous distort from thermal expansion too much for a good Nylon 6/CF pulp mould? I figure that would be much closer to the quality of pistol frames and the polymer that HK and FNH use in some of their rifle receivers.
>>30364620
>>30364287
Like... basically would it be feasible to machine a mould from aluminum, say 7075-T7 billet, and use that, put some holes around the perimeter, use some pins to act as the holes that hold the trigger group to the receiver and have a machined block shaped to the trigger group housing and another for the mag well and another threaded piece for the buffer tube port, the latter two pieces being bolted in to the exterior housing so they stay fixed in place but once it's set can be unscrewed from the housing to aid in disassembly and allowing the buffer block to be unscrewed from the moulded receiver...
What do you think?
What kind of investment would that likely require?
>>30364620
I really couldn't tell you, but you're still looking at significant issues from the viscosity, or lack thereof of the nylon 6, and fiber strand won't help it any.
If you're talking about industrially shitting out piles of polymer lowers as an FFL, you're on the right track. If you want higher quality than two-part resin cast in a silicone mold in your garage, you'd be better off looking at lost wax casting aluminum in plaster.
Aluminum shrinks as it cools, so you'd have to take that into consideration, your wax would have to be 1.0104 to 1 scale.
Usually that ~1% shrink isn't of any concern for people casting bottle openers and shit, but I'm sure that AR tolerances wouldn't take too kindly to it. If you want to use a cast of a receiver to make your wax, it gets even tricker - wax shrinks ~2.5% as it cools, so you'd need to make a mold at a 1.035:1.0 scale, which is just as difficult as it sounds.
some 3D printers can print in wax. That'd be your best bet - print a wax blank in at 1.01:1 scale, smooth over the 3D printer texture the best you can, and drown it in plaster, let it dry, and cast aluminum.
>>30363351
>We need a /diy/-/k/ party one of these days.
May as well include /tg/ into that too. Im a fa/tg/uy and this shit is casting 101. Ive been casting detailed miniatures for years, an AR lower is much less detailed.
>>30364643
If you throw enough money at a CNC machinist, anything is possible. The expense though, would be significant, and I don't see what aluminum molds would do for you that silicone wouldn't, unless you're trying to become an FFL 07 and intend to do injection molding with all the fancy German $100k machines.
For the hobbyist, the best options are viscous two-part resins with fiber and metal reinforcements in a silicone mold (and ideally a vacuum chamber to pull air bubbles out), or 1.01 scale 3d printed wax for lost wax casts.
>>30364824
Miniatures have plenty of undercuts, but they usually don't have entire cavities that you need to be autistically detail oriented about reproducing in perfect detail right down to the threads. I can't think of any miniature that you wouldn't be able to do in a two-part mold, but I struggle to imagine how to do a receiver in any less than three parts.
That said, I'm sure any fa/tg/uy who knows his way around a silicone mold could figure it out in a try or two - then he could ork up the master and have a bonanza making lowers that'd make even Spike's Tacticool cringe.
>>30364762
Yeah fuck that, I'd rather stick away from casting aluminum like that as my metallurgy and forging skills are absolutely nill.
As for the nylon/CF pulp idea, what do you make of this:
Make a sealed vacuum chamber with a 1/2" thick Pyrex top, vacuum down the atmosphere from the mould, have the nylon vat connected with a valve, open the port and as it slows flow, re-vacuum the chamber down again then open the fill valve again till its full and close it off. Let it cure and call shit good.
Disassemble chamber/mould and clean up the seams.
Biggest issue that comes to mind is how to safely heat the nylon 6 mixture I'm figuring I'd likely have to use brass, or aluminum, or steel tubing for the poly feed line. Then have to replace them after each use due to the nylon curing inside of them unless I'm able to punch the nylon out of the tubing
>>30352420
Anyone can make springs man.
https://www.youtube.com/watch?v=jAawhg6JtyY
>>30364549
>>Christ on a cracker are you churning these out like Russian AKs in '48?!
>implying this is a bad thing
>implying we're not tooling up to arm all our neighbors and their extended family
>implying I don't go to sleep every day on a stack of homemade dyneema fabric draped over hundreds, perhaps thousands, of homebuilt weapons
>>30364830
Aluminum molds would allow for casting the high melting temp Nylon 6 mixed with pulp ed carbon fiber to have a lower of comparable strength to poly Glock and Sig and Springfield and S&W pistol lowers and FNH and HK rifle receivers.
Nylon 6 melts at ~430°F
Most silicone I can think of would either lose its integrity or melt before that point.
>>30364852
They used to be way easier to cast. But modern minis pretty much cant be done with 2 part molds for the most part, without breaking them down into thier component parts, which of course makes it not a two part mold.
The way easier option here is to just do an 80% and drill out the trigger group. Which is stupidly easy with resin compared to plastic. The magwell is the biggest gap, but if its a large gap its really not hard compared to the fine detail of modern minis.
>>30364887
>implying i intended that as an insult or negative thing in any way.
I hope you do make tons.
After the wife and I buy a house I'm saving up to buy a mill and lathe and I'll be making my own firearms from stock materials I buy.
>>30350198
>+ 6 transfer fees.
Cuck detected
>>30364862
You'd probably want to keep the mold and tubing heated as well to prevent it from solidifying.
Pulling nylon into the mold under vacuum sounds interesting, but unnecessarily complex for probably not a lot of benefit. I'd look more to having adequate vent flutes cut into the mold for air to escape, and a couple of reservoirs to feed the mold as the nylon cools. Pull vacuum on the molten nylon, pour into the mold, and pull vacuum on the mold. You'd have more flashing to trim from the reservoirs and vents, but you'd probably get just as good of a cast.
The biggest barrier is the fiber strand. That's just going to be extremely difficult to accomplish without injection molding. You'd probably be better off using metal reinforcements inserted into the mold, roughened up to hold the polymer at the weakest points, and fiber mat elsewhere in the mold.
>>30364890
lost wax cast aluminum would be of comparable strength to, well, pretty much anything made of aluminum, and much easier to do as a hobbyist. You'd pretty much just need the wax blank, a bucket of plaster, an electric crucible, a ladel, and a couple of cases of your preferred aluminum-canned beverages or any other decent scrap aluminum.
>>30364896
But where's the fun in casting 80s? Might as well buy them at that point.
The satisfaction is being able to piss some resin into a mold and pull out a fully semi automatic teflon coated salt weapon.
>>30364965
That makes a lot of sense.
My thinking behind the vacuum on the mould is to pull the poly through all the tiny orifices and help remove bubbles and air pockets.
Mostly due to the viscosity of theach Nylon.6 plus the fiber.
I figured the fiber as additive throughout as I remember reading that glocks used a carbon reinforced Nylon 6 compound and I know the polymer in their frames is strong as sit and the same polymer used in a lot of other military equipment ive used before.
>>30364965
>where's the fun in casting 80s
im not saying you cant cast a 100% lower in aluminum, but ive never seen anyone do it and basically you cant do it. If you you could eliminate the machining process from casting and forging ar lowers somebody with a degree and years of experience would be doing it right now and undercutting the price on the competition. A 100% lower cast in metal at the garage tech level is just not happening. In other materials that maintain dimensions properly, sure.
pic related is a cast and forged ar lower. This still requires what I would consider a fairly extensive amount of machining to make usable.
The real trick would be redesigning/designing a weapon that COULD be made entirely with a cast receiver with no machining necessary. IIRC the sks was designed with this kind of low tech manufacturing in mind (pot metal parts will work), but as of yet I havnt seen anybody homebuild one.
HEY For Anons concerned with how flimsy brittle flamable, etc, the resin is that comes with this kit...
Try this website. Industrial grade shit, even one like pic related.
Feel free to look around. I sure as hell spent an hour here. I won't go further into detail as I'm not 100% educated in this matter.
However, I felt I learned a lot just visiting.
https://www.smooth-on.com/applications/model-making/
Also found something here that was interesting. very /k/ related.
https://www.smooth-on.com/applications/model-making/
https://www.youtube.com/watch?v=MSDovg_d5v4
some testing of different casting types
>>30364924
>implying I took it as an insult
>implying I hope you think up new designs and share the plans with everyone
>implying I'm not drinking a toast to your future success right now
>implying it's not my own piss because it's sterile and I like the taste
>>30365206
neat
>>30365416
>drinking your piss as a toast
MEEEE TOO!!! XDXDXDXDDDDD
You uhh... know it's uhh... time... to oil up
>>30365134
I suspect it's not as much about not being possible, but rather that it's not as structurally sound as at least machining out the interior by casting the outer shape then tempering it then machining the insides and such. If nothing else it shouldn't be too hard to cast a lower of aluminum with the lost wax method the other anon have mentioned then breaking the plaster mould and nicking the plaster out from inside it. Then tempering it.
I just think it's likely that the aluminum would be soft enough to not justify the extra time doing cast instead of machining at least on the industrial level.
I'm also curious as to the viability of vacuum bagging a CF lower... just curious as to whether or not it's a viable thing. In theory if you have the lower part of the receiver as the base of the CF (bottom of the magwell) you could vacuum bag CF and formore it with a nut incorporated for the handle and another larger one for the buffer tube threads and a bushing for the buffer retention detent, then just cut out the ends like the bottom of the magwell and the exterior side of the buffer tube hole to open it up for use. Those sound like the least stressed sides of it as long as the rest is solid... I need to get a damn vacuum setup so I can try doing this. Make a mould, then make a resin infusion honeycomb base form, layer CF around that top and bottom sides around the treated nuts and bushings needed for friction support and attachment points, then vacuum bag it and Dremel out the holes that are covered in CF after that process. I wonder....
>>30367137
Or like I just stumbled upon, Tegra Arms makes a CF Composite lower which is essentially what I was looking to do with the vacuum moulded poly idea. It's the same material I was talking about
Found the poly I'm looking for:
Thermoplastic Carbon Fiber Resin Material
www.toray.com/products/plastics/pla_012.html
Aka Thermoplastic CFRP
Another few manufacturers of it
Teijin
PlastiComp
Can't seem to find anywhere to buy it though.
Roechling has a good dataset on it
Pic related it'll definitely have the mechanical properties needed. If it's thermally stable in excess of 400°F once cured Im sure it could be used even for the upper receiver and buffer tube.
Really need to figure out where to get it
>>30352634
>Assuming the reciever doesnt get hot
HA!
also I before E, except after C
>>30365134
>making a lost-wax cast is IMPOSSIBLE!!!
It's time for you to stop acting like a know-it-all piece of shit for ten seconds.
Oh yeah
>>30367137
I wasnt trying to imply that you couldnt cast an aluminum lower, my point was that you arnt going to be able to cast an aluminum lower that then requires no machining to operate.
also:
> then just cut out the ends like the bottom of the magwell
Ive never done it, but its my understanding that cf is a bitch to machine. Also you might as well have aluminum bushing for all of the pins so they dont egg out. The way that other nylon and cf ar lowers are made obviously sets the precedent.
