Tips and Information about making jewelry



With this blog, I hope to share my knowledge, successes, trials and errors, student's work, tips, and information about making jewelry.

Showing posts with label testing metal clay. Show all posts
Showing posts with label testing metal clay. Show all posts

Friday, November 22, 2013

What is the Reaction of Metal Clay with Aluminum?




Over the years I’ve been told not to place my moist metal clay on aluminum or there would be a reaction, so I never have. With that being said, I don’t know what the reaction is! Inquiring minds want to know now! I tested PMC3 and the new Sterling Silver metal clay to find out. 

I placed a sample of each clay on aluminum foil and also samples on an aluminum pan. I cut out a total of four oval discs labeling the discs that are laid on top of foil with an F and those laid on top of the pan with a P. I allowed them to sit there for an hour, until they were fairly dry. 


PMC3 & PMC Sterling on pan
PMC3 & PMC Sterling on foil


The two samples on the foil had a huge reaction as did the foil. 
Reaction to foil

Foil's reaction


The two samples on the pan had less reaction. 
Reaction on pan











Fired and polished sterling silver
It looks like the combination of moisture, clay, and aluminum causes the reaction. The PMC3 clay on the pan had less moisture and so had little to no reaction whereas, the foil seemed to trap the moisture between the clay and foil. I fired each sample per the manufacturer’s directions on the corresponding packages to see if the reaction area would burn clean. It did not. 





Fired and polished PMC3


After polishing each sample, the reaction areas are raised and extend past the surface of the clay. It gives the clay a look of reticulated metal. So, if you want a cool looking texture, now you know how to get it. Otherwise, keep the clay away from aluminum.

Friday, April 27, 2012

Sterling Silver Metal Clay Testing Results with Casting Investment (Ring Plugs)

In September I posted the results from testing the sterling silver clay in August. In this test I found that using an investment plug causes a reaction with the sterling silver clay.

Someone told me that I could place this back into the kiln and fire it again to remove the black.
I did just that and found that it does not go away! I also tried pickleing it in Sparex, it still didn't fade away!
 The only way to remove it is to sand! 

So, fair warning to everyone. Do not use an investment plug to control the ring size. Wrapping it with fiber paper didn't work either.  For the sterling silver metal clay, create the ring three sizes up from the wanted finished size allowing it to shrink down close to the size needed.

Until next time!

Janet Alexander
www.janetalexander.net