Polymer Clay - Lessons learned: Why some of them are brittle

Why   did some of my polymer clay work  break?

This was very disturbing.

I was feeling quite comfortable with my clay work and bought some more clay. Last time I worked mostly with Premo brand.  This time I picked some Sculpey lll as they were on sale in Jo Ann.  But not the Premos.

Some where I read there is not much of a difference among the different clay brands.

I learn a lot from the web and recently  I also  bought  some tutorials from Etsy.  Some of them are just  great and even free, while  the one I recently bought for $12  is totally junk.

Any way, after I doing some hands- on practices, I came to know that some where I goofed understanding  the Skinner blend thing.

 I don't have a pasta machine yet, I was using my rollers.  I was getting some skinner blend effect but not quite  what I had  expected.

Similarly I made some mistakes understanding the Sutton slice  too, but in the process I discovered some thing on my own which I came to know is called Marbelizing.

Any way, I was happy with my new discovery and here are the results:

When they were cured, I mean baked, I let it cool.  Then I sanded and polished and finally varnished it too for the gloss.

I put tiny holes using tooth pick on most of them, but forgot two.  I thought I'd do that when they are dried.

I let it dry for more than 12 hours and then I wanted to finish it with wire work.

I used 20 g wire and immediately one of the earring pieces broke.

I thought I'd use 22 g .  Again the same thing happened.

Finally it took 24 g for the wire work with all the twisting, turning, swirling that were involved.

But why should it be so brittle?

I did not have this problem with the other ones I tried last time?

I researched and found that the reasons could be:

1. I used Sculpey instead of Premo and several sites concluded that Premo is a stronger clay after baking than Sculpey.

2. My pieces were not consistently 1/4 inch thick.  That is one criterion I must remember.  The baking time is 275 F for 30 min for 1/4 inch thickness.

3.  Sculpey says to bake in  275 F for only 15 minutes .  I did it for 30 minutes.  Is over doing bad?  There are mixed opinions on that. So from now on I'll probably use Premo, but be extra careful with Sculpey lll since I already have some of that left, and I like this design with thinner width.  Some  say it is okay to mix two different brands.  I might use the scupeylll as a core with Premo on the top.


I came to realize that unless I  really do it, I can't tell how much I have really internalized this new medium.

 
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