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[geoff p]

Hi All,
Have any of you done any 'back-yard foundry' stuff?

I have a charcoal brazier thing, which Thai people use for general cooking, with an ex-computer fan blowing under the fire - lots of heat, though the charcoal does burn away quite quickly with the forced draught.

My 'pot' is a steel, screw-on end cap for 3-inch pipe.  It is a bit small, really, but it's as big as will fit in the fire.

Melting aluminium is not terribly difficult though using Mole grips to pick-up the pot from the fire gets a little dodgy, to be polite.

My problem is simple:  I have quite a lot of brass/bronze swarf, which I would like to melt-down and re-use.  Last night I tried adding it to a small amount of aluminium (as a puddle of molten metal to carry the heat) but the swarf just sort-of oxidised to a powdery dust.

I know that Aluminium-bronze is a standard commercial material (www.copper.org) so combining the two materials must be possible but commercially they start with copper then add the alloying 'stuff' to it.

Have any of you tried to melt brass swarf?

Is there a flux I can make up from the contents of the kitchen cupboard?  (Thinks, salt, just like the blacksmith used for fire-welding.)

Or just tell me I'm nuts!

Geoff

[HS93 (RIP)]

have a look on this site there is some casting  BUT it can be very dangerous even if the sand is a bit damp so get the right safety gear.

http://madmodder.net/index.php?topic=3841.0
http://madmodder.net/index.php?topic=2826.0
Peter

[Circlip]

You need to look on T'internet for specialist home casting sites Geoff as most on those know what they're talking about. One or two on "Modder" do, but many are suck it and see. Met one of the modders at Arrowgate this year and he is seriously talented, but you can spot him a mile off. T'ain't a black art, you just need the correct info. Be careful, crossing the road is really dangerous, look both ways first.

  Regards  Ian.

[geoff p]

Thanks, both of you.
I started with a 'back-yard' foundry some thirty years ago - melting aluminium in the Rayburn cooker when the wind was strong enough to pull a good, hot fire.  The 'target' in those days was a new propeller for my (very) ancient Evinrude outboard engine.  It was about eight inches diameter; though it was a bit hole-y it did the job.

Later, a local school gave me all their foundry gear - furnace, crucibles, tongs, flasks and safety gear - because 'elf and safety' wouldn't allow it in school anymore.  A foundry in Aberdeen sent me some 'proper' sand, and I was away ... All sorts of things were possibly, so long as it was aluminium.   I made the castings for an astronomical telescope; the headstock, tail-stock and slide-rest for a wood lathe, amongst various other items.  One thing I found was that a re-design (for whatever reason) cost only some gas to re-melt the first-ones and re-cast.

Alas, those heady days are no more, and I live about 7,000 miles away from there.

As already mentioned, though, what I want to do now is use up some of my yellow swarf, and I think Peter's links have already 'set-me-right' on that score: the tarnished surface of brass merely forms dross, so the huge surface-area to volume ratio of swarf would simply make huge amounts of dross with next-to-no usable metal.

So much for that good-idea!

Perhaps I'll stick with aluminium after all.

Geoff
P.S.  HS93, Peter, I've spent all evening reading those threads, and have enjoyed every minute.  Thanks for a good read.