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Cutting up engine blocks & other good sources of alloys
computid - 8/8/23 at 12:11 PM

Hi all,

For various reasons, I've started casting my own aluminium parts, and I'm now looking at sources of cheap, good quality aluminium alloys. Alloy wheels are fantastic as they often have the alloy stamped on them and they're easy to cut up, but finding them cheap enough can be challenging. Pistons are excellent for similar reasons, but much as above they're hard to find cheaply in any quantity.

Which turned my attention to alu engine blocks. Plenty of irreparable blocks around for pennies, and lots of wonderful alloy to be had, but far far too big for me to melt at home! Without spending hours and hours with a cutting disc, does anybody have any ideas for cutting them up? I thought about just taking a gas axe to them but apparently cast aluminium doesn't respond well to that. Open to any ideas on that front!

Also, if anybody can think of any other good sources for quality aluminium alloy please do let me know!

Many thanks!


gremlin1234 - 8/8/23 at 01:14 PM

quote:
Also, if anybody can think of any other good sources for quality aluminium alloy please do let me know!

how about computer disk/CD drive chassis.


[Edited on 8-8-2023 by gremlin1234]


HowardB - 8/8/23 at 03:07 PM

have you tried cutting aluminium with a hand held reciprocating saw - this sort of thing?

I have an old one and with the right blade it is a great tool for cutting many things - including bricks!

[Edited on 1 by HowardB]


jacko - 8/8/23 at 06:08 PM

Plasma cutter but get a good. One


obfripper - 8/8/23 at 06:11 PM

Have you any friendly bodyshops locally, they usually have a good turnover of scrap alloy wheels and their scrap pile usually funds the tea kitty so cash is king.

An old bandsaw is probably the most economic way to chop up an alloy block into small enough chunks, using a 10-15tpi blade and 500-1500 fpm speed should be good. Also, before starting cut into a candle or bar of soap to coat the blade and stop the alloy sticking to it.

Will also probably be useful when you come to trim up the sprues and flashings on your new castings as well.


Dave


Benzine - 8/8/23 at 06:50 PM


nick205 - 9/8/23 at 09:10 AM

Befriend a few local CNC machinists. See if you can collect their swarf. They'll know exactly what alloys they're using and swarf will be easy to melt down.


coyoteboy - 9/8/23 at 09:58 AM

I think blocks are generally fairly poor alloys, as are most cheap alloy wheels. Scrap from machine shops might be better quality. Swarf will be full of cutting fluid. What are you doing with it?


computid - 10/8/23 at 01:42 PM

quote:
Originally posted by obfripper
Have you any friendly bodyshops locally, they usually have a good turnover of scrap alloy wheels and their scrap pile usually funds the tea kitty so cash is king.

An old bandsaw is probably the most economic way to chop up an alloy block into small enough chunks, using a 10-15tpi blade and 500-1500 fpm speed should be good. Also, before starting cut into a candle or bar of soap to coat the blade and stop the alloy sticking to it.

Will also probably be useful when you come to trim up the sprues and flashings on your new castings as well.


Dave


Good point! I'll pop by the local body shops and see if they've got anything.

I would love a big band saw but I'm a bit space constricted. I could potentially squeeze one in but at the cost of other machinery which I think I would rather have unfortunately.

quote:
Originally posted by nick205
Befriend a few local CNC machinists. See if you can collect their swarf. They'll know exactly what alloys they're using and swarf will be easy to melt down.


Swarf unfortunately apparently creates very porous castings, and being coated with coolant etc. makes it a bit difficult to get a good casting out of or so I'm told.

quote:
Originally posted by coyoteboy
I think blocks are generally fairly poor alloys, as are most cheap alloy wheels. Scrap from machine shops might be better quality. Swarf will be full of cutting fluid. What are you doing with it?


They usually have the alloy stamped on them though, which is better than not knowing! I'm mostly casting parts for various bits at the moment, currently a motor mount for my milling machine power feed, so nothing insanely stressed but it can't be cheese either.