Metal Casting Zone

Hi Stephen

Yes i certainly have cast zinc items I got envolved with buying out a fellows business in 2000 and he did a lot of metal fashion items ,badges for clothing and belt buckels I took over the thing and I regreated It from the first week,Near nervious breakdown, anyway.,,,, Did cast some buckels but the zinc is a whole new ball game silicone moulds and zinc which is so so hot to cast , Mould life is reduced consideably . The previous owner said I'd never cast zinc with a electric pot and he was right ,,you need gas to get the temp. and tempature that the zinc is cast at, is not as important as lead tin I am doing now,. I ramped up my pot to 420oc and that wasent good enough to get good results. And if the zinc gets into the lead tin pot it contaminates the pot and you are in real trouble.. I gave the thing away and closed the whole thing down within 3 months , keeped the equipment which some was ok had 400 kg of zinc that i sold to the scrap metal yard. Zinc casting I'd steer well clear of it has bad memories. The only positive with zinc it is very cheap compared to tin lead alloys

Wow John, that puts zinc in perspective. But the good part of that story is within three months you reversed course. Most folks are too proud to do that and go down with the ship.

One of my lady friends makes fun of my marriage because it was only for four months. If that contract, commitment, emotional, financial had been a mistake. Well, what would be worse, four months or four years? Four years of hell and four years later we are still close friends.

Zinc is used a lot in low unit plastic injection molding and as you noted much cheaper. But with the difficulties you noted and the fact that it is the prototype object that is my focus and not the long term replication; I think sticking to pewter is the best path for me. I could actually do with out it entirely by using jewelers bracelet wire for twist formed armatures in my delicate sculptures and have invested heavily in surface color and textures in resin that are still novel in the marketplace.

So I better stick to the simplest surest path in my metal casting experiments. Tin based under 315 Celsius (600F) is quite comfortable working with even the lee melter and the softer silicones molds I have on hand once treated with graphite. The silicones I will be purchasing in March should handle it even better. I am going to be trying samples of several tin based RTV as it is less expensive and matches with a more dexterous family of resins I need to use.

February I will be just sculpting. In my spare time I will be learning with the tin based metals already mentioned. Also learning the use of graphite, talc and mic as I have a sampling of that coming next month. My applications require squeezing some normally unnecessary attributes from parting agents.

I'll use what ever I have on hand for molding material as I am out of silicone until March.

So John what are you working on now?

A small spinner wouild be of great use to you.

I have a commercial spinner and it does a great job with pewter.

Do you know of anyone nearby that has a spinning setup?