Will brass moulds warp?

[fatelvis]

I read that brass is a great material for a mould, but if you get it too hot, there is a risk of it warping. Is this true? I'm concerned because I bought three brass Mihec moulds recently, havent casted yet, but I like to preheat my moulds on a hotplate, and run my alloy hot. Thanks!

[Ben]

It is my understanding that they will definitely warp.

By the way, I own several brass molds and I like them, but I try to be careful with temp extremes that they are subjected to.

Ben

[tomme boy]

Yes they will!

[MikeS]

Brass moulds will warp if you overheat them, but other than that it's my favorite mould material. Cool down your alloy, there's rarely any need to cast over 700F and I usually cast right around 650F with great results.

[Artful]

You can warp any metal with proper or should I say Improper amounts of heat.

[MtGun44]

I can't think of any reason that they would warp any more than any
other metal mold.

Bill

[fatelvis]

I wish I would have known this earlier, before buying these moulds. I like to run my alloy hot, (~800*) I've always had better luck with fill out and really cuts down on the culling. Frosting doesnt bother me. How hot do you have to get these, in order to warp them? Is it fairly easy, or do you have to abuse them?

[44man]

The only molds I seen warped were some I bought used. The handle screws were so tight they forced the mold to warp from heat.

[badgeredd]

The temp of the mold is what you need to be concerned about, not necessarily the temp of the lead. If you cast at 800 degrees, pace yourself to not overhead the mold. If your boolit takes over 10 seconds to start solidifying you are approaching the temp in the mold that could warp it.

Edd

[hermans]

I agree 100% with MikeS....manage your alloy temp between 650 and 700 degrees F, and you should have no trouble with warping, another way that I use to control the mold temp is to put it down on a wet cloth every 10 casting cycles for a few seconds. Mihec's molds are of the highest quality, once you get used to casting with them......you are spoilt forever man!

[fatelvis]

If your boolit takes over 10 seconds to start solidifying you are approaching the temp in the mold that could warp it.
Thank you guys for the words of advice! I would sure hate to spend all that money on such a beautiful mould, just to ruin it unintentionally!

[jameslovesjammie]

Preheat the mould on a hot plate and drop the alloy temp and you will have zero culls and no mould damage.

[Chill Wills]

Is warpage a word?
Brass is my first choice in mould blocks. Great stuff!
Egan, Old West, and NEI brass moulds have all worked with out any warpage for me.
Good advice above and I agree with it but that is the same advice less casting temp that I would give for iron or any block. Slow and easy with heat, avoid banging them around and rough handling, treat them like the precision tool they are, that will keep most moulds working for a long time.

[Frozone]

I use a digital thermometer (see the one offered by NOE) on my MP brass molds.
They all run best at ~ 285º; that is 70 degrees or so above where the Aluminum molds (both LEE and NOE) work best.

They like around 700º alloy as well. I could run cooler I think, But I can't get much under that without spout freeze.

Still not enough to warp a brass mold however. The only problem I have is keeping that much heat in the mold in winter!

It is my understanding that brass is susceptible to warping because of the way the blanks are made - cold rolled.
It is very expensive to get 'stress relieved' brass stock. I'm not even sure you can get it.