Today I decided I needed a short piece of aluminum tube to modify a prototype... I didn't have any so I made a piece. Geez.
- posted
13 years ago
Today I decided I needed a short piece of aluminum tube to modify a prototype... I didn't have any so I made a piece. Geez.
Watch the criticism Bob. We'll have you in the back yard digging for bauxite.
:)
--Winston
Next time, write in and someone here will make one for you. You can afford it.
Steve
Ger Welcome!
Gunner
My junk-collecting dumpster-diving buddy wants me to hook up a smelter in my shop.... goodgawd.....
I've got a foundry furnace built in a 5 gallon steel bucket . Wheels , radiators , extruded stock , cylinder heads , nothing is safe from melting but cans . Too much work for too little material .
What do you then do with your melted/smelted stuff??? Forge it?? :)
And, couldn't you just crush the cans first (in an automated hydraulic 80 ton press, of course), and drop them in with the heavier stuff?
What happens if you melt, say, alum, brass, and steel together?
Sound really neat. Mebbe I WILL get a little foundry thing going!!!
Well , some of it becomes tooling , like the adapter for my chucks to mount onto the rotary table . Some becomes flask parts for sand molds . Some will become decorative trays if I ever get the venting right .
Problem is the coatings and contaminants also contribute to the dross . Not very good stock for machining either , it's almost pure and is very gummy to cut .
Aluminum and brass will melt together , forms an alloy (depending on the base stock) that can be impossible to machine with the tooling I have . Ain't gonna try to get to steel/iron heat until/unless I get a real crucible .
I've got around a hundred bucks into the equipment . I've already recouped that investment from stuff I've cast . The bucket furnace is a modified Gingery design , the burner I'm using is a naturally aspirated Reil type with minor mods for better gas flow . Biggest expense is an adjustable regulator , I was lucky enough to receive one as a gift . Good sand (crushed olivine , for example) is a little pricey , but playground sand that's been sieved to get the bigger chunks out works fairly well to get started .
When I took mickey-mouse metalworking shop eons ago, they had a little
18"x18"x18" bricklined gas-fired furnace, I think for heat treating or sumpn. It used a blower, which was deafening, even tho it wasn't that big -- mebbe a 4-6" diam blower (tops) -- musta had hellified cfm's. With natural gas.I seem to recall the instructor talking about how the air/gas mixture made this thing blisteringly hot, much hotter than a regular gas oven.
How much hotter, I wonder? Do you use a setup like this?
Would an oxyacetylene setup make sense, be at all economical for run of the mill smelting? Or good only for special projects?
You'd burn through a lot of gas without a lot to show for it. Acetylene burns HOT, but doesn't have a whole lot of heat per unit volume. Air/natural gas or air/propane will do the job a lot cheaper, or you can go with a blower and the Gingery route and use charcoal in a modified bucket. Insulation has changed a lot in the last decade or two, you no longer need buckets of bricks to line a forge or furnace and it's a lot more efficient. Space shuttle technology at work.
Stan
O/A is expensive. I don't think it's practical for anything beyond jewlery work in thimble sized crucibles.
What Pete and Stan said . The Reil design burners I use burn LPG (no blower) and I can have 5 lbs of aluminum melted in under a half hour - for the first melt . Once the furnace is hot , I can melt the same amount in under 10 minutes . There's a ton of info on burners at
Works fine for crucibles significantly larger than that, easily works for cup sized crucibles. But I have also used clay and grass open hearth with charcoal for that same size with bronze. Not a whole heck of a lot slower.
jk
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