Marine Man

Hi All,
I have been lurking in the backround for a while and I must say this is a really great site - well done!

My brass scrap box is growing rather full and needs to be smelted down and recast. A couple of years ago I did the job using an old clay pot as a crucible which worked for a few times before finally cracking. I cast round stock using the inner bore of large diesel engine gudgeon pins as molds. I must say it worked a treat and the cast stock was some of the best I have ever machined! (must have had just the right mix of everything). I was wondering if there are any suggestions for more durable crucibles, short of expensive carbon ones?

Machining-wise I have just finished juniors oscilating steam engine, and am now working on a Stuart D10 kit of castings.

Look forward to hearing about crucibles. Thanks guys.

Bluechip

Welded from steel ?? No, I don't do casting, just know of this site ... so don't ask ..

http://backyardmetalcasting.com/crucibles.html

Dave BC

abby

If you are serious about casting buy a couple of plumbago crucibles, At around £25 for an A8 the cost is small and treated with care they will last for years casting brass.
Don't use flux in your melt as this will eat the crucible away in no time.
Steel is useless and can fail with dangerous consequences.

doubleboost

Hi
Steel crucibles can be used ok for aluminium
Ceramic is best for brass & bronze you also get better heat transfer in to the metal
This link should take you to how i make steel crucibles
http://www.metalworkingfun.com/showthread.php?tid=153

http://www.metalworkingfun.com/showthread.php?tid=581

I hope i am ok posting links
I will be posting alot more on hear now that certain people have gone to pastures new
John

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The downstairs loo is very handy for cooling welded parts

abby

When replying to a question I try to give relevant , safe , advice always based on my own experience and not on what I have read somewhere.
The question was "what is the best crucible for melting brass" not aluminium.
Even though it is common to melt aluminium in a steel pot I would not recommend it unless a suitable internal wash has been applied.
Steel dissolves readily in molten aluminium , not only contaminating the melt but gradually weakening the container.
You would wear the correct protective clothing for any hazardous operation , why skimp on the tools ?

doubleboost

I totally agree with you ceramic crucibles are the way to go
I needed a big crucible for one pour (i could not get a bigger ceramic one in my furnace)
All i was trying to show was how to make a steel crucible as safe as possible (have you seen what some people use)
John

__________________
The downstairs loo is very handy for cooling welded parts

oilmac

I worked in the foundry trade & i can concur with Abby, that steel crucibles are an absolute No No for melting brass &bronze in, & i would go the length of saying the same goes for melting aluminium, In the case of brass &bronzes, taking aside the melt contamination, with the high temperatures one is melting at, & by and large the construction of your crucible ( it is more than likely constructed with a welded base,) One has a recipe for a serious accident, Molten metal is a very unforgiving substance, It does not take a lot of it to do serious damage to a human

I feel for what it is worth for peace of mind, the cost & use of a clay graphite crucible is very much worth considering. Saying that look after your clay/graphite crucible Keep them in a dry environment between use, Dampness & water is the mortal enemy of crucibles

Remember our hobbies are an area of our lives for relaxation and enjoyment, not to be marred by cutting corners

Tin Falcon

can you yes recommended well my gingerly book that tells one how to make them has disclaimers recommending you buy them.
so yes you can make them but it depends on your skill and knowledge of doing so . and therefore no guarantee.
tin

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Ad maiorem dei gloriam - Ad vitam paramus
amat victoria curam

rhitee93

Smaller crucibles are really pretty inexpensive, and readily available. I make just about everything myself, but plan to buy a crucible when I finally get around to casting some parts.

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-Brian

Atzerath

Where could I buy a good crucible online In Europe??
I f*ck*d up 2 steel pots today when trying to melt aluminium....
I sure did smelt it but I'm stuck with an aluminium blob mixed with coal...