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POTTERY, CERAMICS, POLYMER CLAY => Polymer Clay: Discussion and Questions => Topic started by: ashasaurus13 on June 10, 2009 10:33:36 AM

Title: newbie with question thats probably stupid
Post by: ashasaurus13 on June 10, 2009 10:33:36 AM
I couldn't find anything on maybe I'm the only one who has this problem?
I'm using sculpey clay and i made the cutest little dinosaur  in blue and bright pink and I baked and baked it because it wouldn't set. then after 30 minutes(when according to the package mine should have taken less then 15 minutes) of baking i decided id have to take it out and then my colors were so dark and un-cute and it still doesn't feel like its set because its kinda bendy D:?
why did this happen to my innocent little dinosaur?

Title: Re: newbie with question thats probably stupid
Post by: Diane B. on June 10, 2009 11:14:30 AM
(Not stupid at all... those are common problems for new clayers, unfortunately!)

There are a couple of things that are or could be going on with both the darkening of the colors and the "bendiness" of the clay.  

First, all polymer clays darken a bit when cured, but especially certain brands (like Sculpey III, SuperSculpey-flesh, and original Sculpey) as well as certain "colors" of clay (translucents, or any color with a lot of translucent in it--which isn't often obvious at all).  Kato Polyclay darkens the least, and the others are in-between.
One way to help with that is to add a bit of White to any color... that will both pre-lighten the color so the darkening won't be as great, and since white is always quite opaque will counter the translucent clay.

Darkening can be made worse if the temperature that actually reaches the clay --at any place on the clay, for even a short time-- gets higher than about 265-275 for most brands (original Sculpey can't even be baked that high).  That actually happens in most ovens, so it's at least essential to preheat, to use an oven thermometer near the clay to see what the actual temp is and if it stays the same, not to put the clay too close to any oven coils or sides and to avoid any "hot spots" in an oven, not to use certain baking surfaces, and possibly to protect the clay from excess heat by using a partly- or completey-enclosed baking method.

You can read lots of detail about all those things on the Baking page of my polymer clay "encyclopedia" site: especially on the category called Darkening, Scorching, Burning

As for the "bendiness," you've either not let the clay cool before bending (it softens when heated, until cool), or you've underbaked the clay (too low a temp and/or too short a baking time).
Also most all the brands will be quite flexible if they're thin, even after cooling --polymer clays are different than earth clays in that regard, and won't be quite as "hard."  Actually though, the 3 Sculpey lines I mentioned above are fairly stiff and hard  after baking compared to the other brands and lines of polymer clay, but that also makes them more brittle if they aren't fat and rounded (so easily broken).

You can read much more about that on the Characteristics of Clays page at my site too: on the category Strength--Rigidity, Flexibility
Be aware though that that particular page is having a display problem if you're using Firefox... the problem may be fixed for Firefox later today).

You can also check out that Characteristics of Clays page at my site if you want much more info on all the brands and lines of polymer clay, as well as their handling and other characteristics.

For beginners btw, I usually suggest using Premo or FimoSoft--which has a bit less strength but still better than Sculpey III.  (If you have hot hands or live in a hot area, you'd definitely just want to start with Kato Polyclay or FimoClassic though.)


Diane B.

Title: Re: newbie with question thats probably stupid
Post by: ashasaurus13 on June 10, 2009 11:46:05 AM
Thank you so much, this is very helpful! my peice was rather thin so that explains why it bent.. hmm