https://youtu.be/hHD10DjxM1g
Thoughts on this guy?
I was interested in making one of these mini forges but I don't know enough about it to tell if theres a smarter way of doing it
seconded
Pretty sure that thing is only good for aluminum. Which doesn't mean you shouldn't make it, but just don't expect it to be more versatile than turning cans into knick-knacks.
But it does seem like if you want to melt aluminum on a hobby scale, that's a pretty damned good way of doing it.
>>988916
I've built two now, it works pretty well for aluminum, I haven't tried anything else though. I think it's good for the amount of money spent building it.
>>989295
Yes you can. They're called letter openers.
>>989295
Nope, but you can cast some pretty sweet ornamental bolsters and fittings for them
The other use for the little foundry's is that they do just fine for heat-treating blades for hardness.
>>989295
Aluminum cannot be forged or hardened. It's useful for projects that require low weight metal castings. Functional knives and hand weapons are not really possible however.
However, this is a very simple, inexpensive, and relatively low temperature furnace. I think it would be good experience for a more substantial furnace capable of melting copper and other metals to make bronze, which would be more useful for such things.
dual purpose structure.
Make a brick forge that can also be used for cooking.
Can you make bronze in them? I really want to see more bronze weaponry around.
>>988916
I made the one he made in his video. It works pretty well just make sure there's enough room for charcoal around the crucible and you're good
>>989388
The trouble with this particular furnace is that it uses a steel crucible. That's fine for aluminum because aluminum melts at around 650C, and at those temperatures steel retains almost all of its strength.
To melt copper (the primary ingredient of bronze) you need about 1100C. While steel melts at around 1350-1450 (depending on what kind) it loses the majority of its strength long before then. At 1100C your fire extinguisher crucible would be really soft, and might not be able to withstand the weight of the bronze.
That's assuming you're running your furnace right at the melting point of copper, which won't be the case because it would take too long. At the temperature you'd run the furnace to melt a significant amount of copper quickly and economically, your steel crucible would have the strength of wet cardboard and would almost certainly fail.
You will want to make a ceramic crucible.
>>989435
Looks like the erectile dysfunction graph
Same guy has a video on how to make a propane torch for the foundry which will allow you to melt shit like copper, assuming you have a decent crucible.
>>989435
How does one make a ceramic crucible?
Also whats better for crucibles ceramic or graphite? I've seen some graphite ones around for pretty cheap.
Is a ceramic crucible just a ceramic cup I want one and I have full access to a ceramics studio but I'm not sure if a normal clay would withstand heat that could melt steel?
>>989673
Stoneware clay is generally used for the lower temp stuff (unglazed), not quite sure what's used for the higher temp stuff
>>989673
Steel is a different beast altogether. We were talking bronze, not steel.
Casting steel is pretty much beyond the scope of the hobbyist.
>>989673
silicon carbide
>>989502
get castable fire cement
I made one similar to this but with high temp castable refractory, I haven't gotten to play with it much since school started but it melts aluminum perfectly fine and i have gotten mine up to copper temps but i didn't do anything with it. I would recommend a well made propane burner for anything over aluminum though, I use charcoal and coal and the temp has a tendency to fluctuate. This summer I plan on building a forced air propane burner for my furnace so I can maintain the temps easier.
I recommend the design for a hobbyist but with a few modifications to make it more durable.
>I recommend the design for a hobbyist but with a few modifications to make it more durable.
Such as?
>>989929
Not him but
>use fire cement not plaster
>have the burner or blower attached off centre (see pic) - so flame circulates around the crucible heating it evenly instead of hitting it on one side. Your furnace should always be round as well, for the same reason.
>the part where he forms the inner chamber using a plastic bucket which he removes latter is dumb, use a steel bucket, leave it in there - your furnace is always more vulnerable during its first few firings, moisture is still escaping, the steel will support it until it's fully fired/fused/whatever.
>always slope pipes downwards into the furnace or have them raised off the base. That way if your crucible fails you don't have molten metal pissing out down your blower/burner pipe onto the floor.
Is this torch/burner enough for a foundry?
Wandering /k/ommando here: How difficult is it to cast aluminum into a complex shape? Like, say, pic related?
>>990589
Basically, if you can make it out of foam, you can make it into aluminum by putting a foam copy into some really fine sand, and when you put the molten aluminium in, it instantly melts and fills in where the foam was. But you know, aluminum isn't exactly known for its durable qualities, so it might not be too practical in your situation
>>990589
Middling-hard.
>>990593
Lowers are made from aluminium.
>>990589
You can do it, but it'll be pretty rough and I wouldn't trust getting the pin holes right. So, you're going to have to do some machining anyways...
>>990604
Lowers are milled from aluminum.
>>988916
I fell for this meme too
it ended up costing 50 bucks plus fuel
should have gone with electric... You can save like 5 bucks per melt
>>990589
Receivers (at least good ones) are generally made out of forged aluminum, which is a very specific alloy that is compressed into a billet for later machining.
I guess you could technically cast a roughly receiver-shaped billet yourself, but I think pop-cans to 80% is outside the reach of the hobbyist. Also, the casting would be even weaker than factory-made cast receivers due to impurities, dross, etc, and the wrong aluminum alloy. And the outlay for the furnace, the fuel, the supporting equipment, and of course the machine tools would be more than just buying a stripped lower.
tl;dr - probably not a good idea.
>>990871
It's usually possible to pick up snapped/damaged/old bike frames for cheap/free from the local recycling center. Being that those are often a very high grade of aluminium to start with are they worth chipping up and melting for higher quality casts?
6061 seems to be the most common at the moment, I have a couple old 6061 frames that are too battered to use or resell, I was going to make them into garden ornaments but melting them might be fun too.
You should get jet fuel.
Its the only thing you need, it melts steel.
>>991579
He's right, jet fuel melts steel beams, nothing else cuts it.
>>988916
>fucking grill tongs to hold that crucible of molten aluminum at 5 minute mark
jesus fucking christ.
>>991515
I don't think the starting grade of the aluminum stock is going to make much of a difference. The difference between cast aluminum and forged aluminum is that cold working the metal alters the properties of it. Forged aluminum has been compressed with a hydraulic ram before machining, which hardens it. Cast aluminum without the compression will always be much softer.
You certainly can make a receiver out of it, but it'll be a shitty receiver. You can already buy a hard anodized 80% forged receiver for like $60, so I don't see the point in making a furnace, a crucible, sandcasting or investment molds, etc, and actually casting a receiver that you know is going to be shit before you start.
https://www.youtube.com/watch?v=sEc5Jak9jsg
I just used fire bricks. The sand, plaster, setup, too much fucking about compared to bricks.
>>989295
A good way to think about it is this:
you can sharpen anything you want to the point that it cuts. The difference is how long will it stay sharp.
>>990642
mind liking me to a good electric furnace?
>>988916
Was planning on making one next week. Was going to order a crucible online so i dont have to worry about the steel melting
>>990309
Nice
>>990642
You can always make your own charcoal, which costs nothing if you have scrap lumber or land that needs to be cleared of trees.
>>988916
Will this foundry melt silver and or gold?
>>988916
Speaking from experience, it works really well. But as someone who has used both coal and propane forges, it's not at all cost efficient if you use charcoal since it burns up extremely fast.
That being said, I managed to get the internal temperature so high that it melted the steel pipe used for the air flow. I'd say do it if you're working on small projects but be prepared to work quickly, and if you're beating out metal instead of casting try and find a shady spot. Personally I would like to set it up somewhere open air with a roof, but I'd still need to construct a chimney since it gets really smokey.
The main thing to think about is the air flow since stronger air flow = hotter internal temperature. I have a hair dryer hooked up to mine and it works really well, but if you get something more powerful you'll be able to heat things faster at the cost of using up your fuel faster.
>>992709
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=40&t=6355
Is it necessary to strip paint or coatings off of aluminum before melting or does that all burn off?
>>995065
it ends up as dross that floats to the top that you skim off before you pour
>>995065
Nope, just drop your cans straight in. Just pay attention when pouring out the liquid aluminum
Our local scouts group switched from bottles to cans a while ago (people were too lazy to pay for a glass of soda, but willing to pay for a can. People are weird).
We bought one of these and now once a month just melt the cans. Tried bottle caps, but the foundry just doesnt get hot enough for those.
It works quite well, but you need a shitton of cans to get a decent amount of liquid aluminium.
Also, when building the foundry we did not have the plastic bucket laying around. Someone had a huge candle laying around so we just melted that. Worked surprisingly well.
We do need some ideas for the nuggets of aluminium. Was thinking about making some lampshades or something. What do you guys with the nuggets?
anybody know where I can buy alumina-silica bricks from? I wanted to build a bit larger furnace but these bricks are basically impossibly to find at a reasonable price.
>>989295
Not one that you would want to take out to the woods. Aluminum doesn't sharpen well. I casted a knife before out of aluminum and tried to sharpen it. It just doesn't hold an edge.
I'd love to get into this kind of shit, but being a university student makes it pretty much impossible
Tried it, didn't work too well. I'd recommend this one instead
https://www.youtube.com/watch?v=9XO1rE7v44g
>>990581
definitely if you want to spare time and spend on propane this will do for making swords
>>990589
You could try copper or brass, it might be heavy as shit bit it will look cool.
