Casting aluminum on a backyard

[john.k]

Cans are worth a 10c refund here .....never see one ,not even the stainless ones....When I was a kid ,a guy down the road used old motor bike alloy to make pulleys ...Indians,Harleys ,Hendersons ...all went to make pulleys.

 

[brino]

Cans are worth a 10c refund here .....never see one ,not even the stainless ones

The beer stores here have stopped taking back bottles and cans for deposit (due to covid-19).
They are starting to pile up.

If the aluminum to other(paint, interior coating) ratio was better, I would consider melting them down.

I might start throwing them in the blue recycling bin........

-brino

 

[speedybtx]

Source from Sand castings, eh ? So old Maico Dirtbike engines. NOOOOOO ! save them!

 

[Diecutter]

Large aluminum castings such as transmission housings can be heated up (in a log fire, with a weed burner, etc.) and then easily broken into crucible sized pieces with a hammer. The temperature needed is way less than melting temperature. I have also had luck in sawing aluminum auto cylinder heads into pot sized sections on my 4x6 bandsaw, then simply fishing out the valve seats, guides, etc. when the sections melted.

 

[r3292c]

Here is one more experiment. I tried to compare green sand to water glass sand on the same draft.
My water glass sand was more sticky, so I had much less loose sand with it. The green sand was made of finer sand, it provides smoother surface on non-machined areas. This is also expected. But what wasn't really expected that porosity is much better with water glass sand. Do you think that the water used in the green sand may cause more porosity? All other conditions were the same - the same batch aluminum, the same foundry, the same Borax used, about the same casting temperature...
By the way, when I pour aluminum to a tin can, the porosity is also much better than with using green sand.

 

[Cheeseking]

If we need good finish we use a zirconium (zircon) sand. Its a pain tho making a separate setup apart from the silica/air set line.

 

[Nutfarmer]

A little trivia on aluminum cans. The lid ( top of the can ) is 5182 allloy. The inside of soda cans are coated , while beer cans are not. Beer is not as corrosive as soda.

 

[Larry$]

I do a little AL casting. My favorite video site is Olfoundryman. I fire a home made furnace on propane. Use a clay/graphite crucible. I bought a commercial degassing product. Helps but not absolute. I just buy fine sand at Home Depot & bags of Bentonite at the local concrete company. I use sodium silicate & sand for cores. I bought a cylinder of CO2 to set the sodium silicate. Have never tried baking an oil, sand, clay core. Depending on what I'm making I'll use about any alloy. But for best result with scrap I like old automotive castings. I think pistons usually have 10+% silicone. Things I've made with them came out OK. Extrusions are less than ideal but readily available and OK for many things. I get 6061 cut offs from a machine shop. Melting cans is a waste of fuel. I've had some zinc get mixed in and like the resultant harder(?) less gummy machining characteristics. Controlling shrinkage seems to be mostly in the design of the mold, use of gates and riser-size/ connection. limiting oxide inclusion is done with pouring so the oxides are kept floating and not entering the mold. I've been using a pouring well and a quite small tapered sprue that has been better than my previous attempts at just using a hole left by a piece of 3/4" piece of copper tube.

 

[brino]

I do a little AL casting.

Indeed. Lots of details and hints packed into that post.
Thanks!
-brino

 

[r3292c]

Casting of a hand