Metal Casting Zone

I am getting ready to order more metal. These are the two alloys I'm considering:

"Tin / Base Fine Pewter (Lead Free)
approx 90% Tin, 8% Antimony and 2% Copper. The copper makes the metal more ductile so that it can be formed easier with a hammer if necessary. Melt Temp Around 466 deg F"


" alloy with approximately 92% Tin and 8% Antimony and containing no copper. Melt Temp Around 466 deg F"
(taken from the company website.)

I have been using an antimony free alloy containing tin, copper, bismuth and silver and my problem is tarnish. Because I make jewelry, the oils in the skin will dull this alloy down in a year's worth of time.
I was told by an artist that pewter NEVER tarnishes and that the silver in my alloy was the culprit. I have been using antimony free pewter because I read that antimony can be toxic in larger amounts.

Also what differences can I expect with copper/no copper in my alloy?

Can you help me decide on my next metal purchase? I want to get rid of the potential tarnishing and need more info on the danger of exposure (if any) on using antimony in my alloy. I have a home studio with two small children and I want to be safe and have a quality product.

Thanks to anyone who shares their time~

Welcome to the forum!

There is a small article on Pewter on down in the forum, I just read through it last night. I don't know much about it. I imagine antimony is a lot like lead. Lead isn't very harmful as long as it is in the metalic state. If it is heated to boiling them it releases lead oxide and that is harmful. I've handled and melted printers type for years, it has Lead, tin and antimony. I get tested every six months at work for heavy metals and have never had a problem.

Hi miss Dee
You sound as thought you are walking along the same path as me with your interests in casting .Jewellery casting and spin casting in pewter.Hope I could give you a few ideas ,,your picture of the pendent looks good .. is it spun cast in silver or pewter??/
Your reaction with silver is not new to me. Possibly you could think of having the items in silver Rodium plated ,in my company we rodium plated the silver mens ring all the time and this help from tarnishing problems. At least for a few years.Don't know of the Antimony as toxic ,lead is more of a no no than Antimony. Antimony gives the alloy strength and have read that it desolves in a lead alloy but doesen't melt. For safer metal you could cast all in sterling silver. Sterling silver is only fine silver with copper for strength, Silver jewellery is stamped 925 indicating 925 parts per thousand pure silver , So maybe cast in stg sil ,rodium plate the items, safe metals no tarnish.Keep me posted on your casting projects.

Johncast,
Thank you for your time!
My work is all spuncast in pewter. I don't have the means yet to work in silver. My pewter alloy contains silver though, which i think might be causing my tarnish problem.
I might choose then to switch to a pewter alloy with Antimony and no Silver content.

I would love to be able to rhodium plate items that I cast. I have tried to find a company that would do it locally but I live in a small town and haven't had much luck. Is it something that would be viable for a small scale studio?

Make it Hot,
Thank you for your time! I'm glad to know that the antimony is not a safety issue.
I will check out that post and see what I can learn!

Hi Miss Dee
Well I,ve broused over your web site and enjoyed looking at the designs the whole range is a credit to you. You love what you do I know how you feel. How do you like the Romanoff spin casting unit you have in the photo.? Very similar to mine. To set up to Rodium plate needs a little equipment. Power source DC, Ultrasonic cleaner,these are expensive , unless you already have one. Small baths for the solutions.The prosess needs a lot of practice and trial and error to get right.It is a little like the stripping process I did at my workshop a few years ago,there was a lot of constantly changing perameters to keep track of ,power output ,size of item,gold or silver ,temp of solution,duration of item in bath,on and on sometimes very frustrating. Small setups are not hard to do as many jewellery manufactures plate their own items. Certainly worth looking into . If some of the items are sculptured, do you use milliputty for the sculpting?.I have used this quite a lot for my model componets and you can place it directly into your spincasting rubbers for valcanizing.

Hi miss dee

sounds like you have not got your metal hot enough you are casting your pewter around 240c and you would probably have better luck at around 280c or about 536f .

Just because your pewter melts around that temperature does not mean that is the best working temp my pewter melts at 220c but it is not worth a hill of beans till it gets to about 280c.

This is vitally important if you are spin casting you will have a lot less rejects and more fuller sprues.

You will however get porosity if your metal is to hot mould life could also be affected by higher temps my advice to you is contact your supplier and ask for a recommended WORKING TEMP for your metal.

I hope I have been helpful

Miss Dee,
I found this link to lead free pewter alloy. At around $15 per pound with a 25# minimum. Ouch, includes shipping. If you didn't want that much maybe we could all go in together at 5# each or so. Just a thought.
www.purityalloys.com/Pewter_Alloys.html