Casting Aluminium (not aluminum, you yanks just cant spell gooder!!!!)

[Camel]

Thanks to Camel I now know that almost all the extiguishers I have are T6061, one is T7060 and bugger me if it isnt corroded around the neck (white powder coating). Its to be set aside.

Just out of interest, what's the difference in weight between the 6061 and 7060 cylinders?  The 7060 might come in quite useful for other applications.

[artie on edge]

  Ha!  Thought you might!  Here come those rear uprights!  You'd better be quick though......

Artie, are you using a waste oil furnace?

Where do you source your crucibles?

And isn't bentonite (kitty litter) a better option than oiled sand?

Camel

No mine is coke fired and air blasted.

My crucibles are bore casing from water bores. Fairly common out here in the sticks and come in a variety of diameters. Normal mild steel would be ok if you are only doing ali but mine can also handle cast iron.

Green casting sand (mix of fine sand, bentonite clay and water) has several advantages over oiled sand but also several disadvantages.

Basically it will cast to a much finer surface finish but has a long lead time before you can actually cast in it. (ALL moisture must be removed so if the casting box is too big for your oven it will take days to dry sufficiently).

Oiled sand can be molded and cast from immediately. Im moving to green sand for my next item.

Doug, check the thread on casting ali housing in fabrication for more details.

[cleppla]

Where do you source your crucibles?

I had seen people use 3 or 4 inch round pipe threaded with an end cap used for a crucible.


Chris

[cleppla]

where does the heat supply come from? and what is the operation and involvment. With all that swarf I have Im starting to brainstorm. 

 I made my own furnace a few years ago with concrete, perlite and sand mixture in a small metal trash can.  I was able to melt aluminum using charcoal and an old blower fan from a dishwasher. The aluminum came from old car parts.

Not sure if this was posted yet. Tons of info. http://www.backyardmetalcasting.com/

Here is the recipe on the foundry material,.

http://www.visi.com/~darus/foundry2/refractory.html


Chris

[b.c.bugger]

hey, 6061, I win I win!!
What's my prize??

[artie on edge]

hey, 6061, I win I win!!
What's my prize??

he he he.... you lookin mighty purty lil american man..... 

Well done btw!

[b.c.bugger]

easy now, I may be purty but I aint no 'merican

[SPEC]

 

[artie on edge]

easy now, I may be purty but I aint no 'merican

awww close enough......


 

[Doug Heim]

OK so all this swarf I have, I figure I could cast a bunch of discs to machine some more hubs and or bearing retainers from. So all I need to do is make up some steel "bowls" (crucibles? not familiar with terms here)
and pour into those? Should the bowls be pre heated?

I still would like some details on how I can melt the stuff down easily. Is it a matter of just building a insulated "box" (furnace) and throw heat into it. What type of heat are we talking for 6061 t6?

[XRH348]

[artie on edge]

OK so all this swarf I have, I figure I could cast a bunch of discs to machine some more hubs and or bearing retainers from. So all I need to do is make up some steel "bowls" (crucibles? not familiar with terms here)
and pour into those? Should the bowls be pre heated?

I still would like some details on how I can melt the stuff down easily. Is it a matter of just building a insulated "box" (furnace) and throw heat into it. What type of heat are we talking for 6061 t6?

noooo... The crucible is the bowl which you melt the scrap in, then you pour it into a mold.. ill try and find you a link to a site that shows you how to make a foundry...

[Doug Heim]

Awesome... Thanks tons!

[artie on edge]

Well I guess no one will want to go with charcoal (im old fashioned so heres the burner

http://metalcast.boorman.us/reil_1.html

And of all the foundry 'recipes' that ive seen, this is probably the best of em... however, I would 'upsize' this a bit. Mines a 60 litre castrol oil drum and is big enough.

in fact after reading these, expect mine to be gas fired when you next hear from 'her'......

http://incolor.inetnebr.com/bill_r/fun_with_molten_metal.htm

Much is made of the 'housing' these things are made of. It isn timportant apart from the size. The insulation in these things is soooo good that at approx 1300 deg F I can 'almost' place your hand on the outside. Mine has the original castrol paint job still in good order. The difference from here is mine has a layer (1"?) of insulwool in the casing before the the refractory cement was put in place.

[artie on edge]

Well, I had previously decided that I didnt like the big lumps of steel that I had made the bearing carriers at great cost of time. They are just far too heavy.

So Im going to cast them up using the hard ali I just got my hands on.

Out comes Alibre again, mock up the unit for the casting plug and here she is.






The lug on the end is so it can be mounted in the lathe and is gone when its finished as that space is wide open (see last pics)

And here it is in the flesh..... made from MDF (wood, sort of) and sealed with enamel, a bit more filling required yet.....



And in case you are unsure, this is where it will sit once cast.



It will take the place of this unit I previously made from steel....






This is what it will look like once its been machined up....