Metal Casting Zone

Hi All,

I'm new to the forum, and somewhat new to casting. I use to work in a steel foundry years ago, making sand molds and working on the pouring floor, so I know a little bit about it. I had a couple questions regarding pouring zinc. My aim is to create some zinc anodes for my sailboat and I’m not sure how to increase the size of an original part to compensate for shrinkage?
Also, I'm looking for a good source to buy zinc from?

I'm sure I'll have a lot of questions as I get into this more; I'm collecting parts to build a furnace right now. I'd appreciate any help.

Thanks...Jeff

Hey Jeff! welcome. Sounds like you already know what you need. Look up online shrink tables for the particular alloy you are going to be using. As far as where to get it, there are lots of suppliers online, just be prepared for sticker shock. Might be just as cheap to melt pennies. (Note: for the government types out there monitoring this, I am not actually suggesting anyone melt down currency, which is highly illegal, unless it's Canadian pennies, then go for it... )
Look forward to your progress.

Hi Jeff,

How pure dose your zink have to be? If you can find scrap die cast most of that is 96% zink. Good luck.

Peter.

if you want to just "enlarge" the pattern.....dip it in wax...you can multi coat this and trim back

I buy zinc at rotometals. I am not sure if it is a good price or not really but I use pretty small quantities so i don't worry too much about it. I do love coming home to a flat rate USPS box full of 50lbs of zinc bars.

i collect it up from old old car grills ...door handles....most is plated with chrome.

I do the same thing. I melt down anything made of zinc and to make it work better, I then throw a couple of aluminum pop cans into the melt.
An easy way to tell if it will pour well is to pour a small amount on a steel plate and see how it looks on the surface after cooling.
If it looks smooth and not like styrofoam, then it is ready. If not just add another pop can.

Coley wrote:
I do the same thing. I melt down anything made of zinc and to make it work better, I then throw a couple of aluminum pop cans into the melt.
An easy way to tell if it will pour well is to pour a small amount on a steel plate and see how it looks on the surface after cooling.
If it looks smooth and not like styrofoam, then it is ready. If not just add another pop can.i love melting the stuff! just a large soup ladle on a gas stove....enough for a 500 gr pour.