cracks in polymer clay- baked too long?

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BigguyZ

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I recently purchased some polymer clay (last night), and the blanks I made have cracks in them all over. Not huge, but enough to be a concern. If I was going to use CA, I don't think I'd worry, but I like the feel of the bare clay. Is this because I baked the clay for too long? I baked at 275 like the package said, and they were in there for a bit over an hour (they were thick "rods"). But I noticed that the colors on the Green and Yellow clays are uneven in color. The Yellow browned a bit.

Also, I didn't have the greatest adhesion between the different layers. I rolled the layers out in between sheets of wax paper, and folded to make a Makume effect. But there were a few bubbles and some plys didn't adhere very well (though some definitely adhered).

Lastly, the clay was pretty stiff out of the package. Can you warm it to soften it up and make it easier to work? Can you overwork the clay?

Lastly, I made a pen with just the polished clay, but is it something that really needs finishing, or is it OK by itself?

I really like the material so far, so I'm excited to learn more about this stuff.

Thanks!
Travis
 
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DozerMite

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The clay needs to be conditioned before it can be used. To do that, just run it through a pasta machine until it becomes soft and pliable, approx. 10 - 15 times through. Baking times and temps vary a little by brand. The yellow turning brown sounds like it burned. The cracking can come from baking too long, but sounds more like it wasn't conditioned. Hope that helps.
 

nava1uni

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Did you sand the tube before applying the clay. You can soften the clay with contact with your hands, just knead it after just holding it in your hands. Different polymer clays are easier to work. Sculpey is softer then Fimo. There is a diluent that you can use to make Sculpey a little easier to work. Baking for an hour is way too long. You can bake a pen in about 20 minutes because the metal tube transfers the heat from the inside and makes it bake quicker. Any discoloration is an indication of overcooling. If you are making rods then it will take longer to cook, but you can insert a wire down the middle of the rod to help with it baking quicker. PM with any questions.
 

BigguyZ

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I made solid sticks, and drilled one of them out. Was able to get a smooth finish after using CA. Would have preferred keeping it with just the clay, but whatever. Do any of you leave the clay without a finish and just polish?

So, the clay should get easier to work the longer it's handled?

What are the pros of wrapping the tubes, rather than drilling? I would imagine that you would save in materials- but it seems to me that the patterns would be different rolled onto a tube than it would be mase solid and drilled.
 

ngeb528

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If you want the 'natural' clay look, you can use one of the mid grit MM pads to dull it a bit. Just a thought.
 

PaulD

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I made solid sticks, and drilled one of them out. Was able to get a smooth finish after using CA. Would have preferred keeping it with just the clay, but whatever. Do any of you leave the clay without a finish and just polish?

So, the clay should get easier to work the longer it's handled?

What are the pros of wrapping the tubes, rather than drilling? I would imagine that you would save in materials- but it seems to me that the patterns would be different rolled onto a tube than it would be mase solid and drilled.

You can just use a plastic polish on the clay and it will give you more of a satin finish. I've done polymer with and without the CA and both approaches seem to wear just fine. The big pro about wrapping tubes, aside from the obvious issue you noted, is that it is the only way to really do millifiore and other canes with some design integrity. And yes working the clay by hand will soften it, but I agree the pasta machine approach is easier.
 

BigguyZ

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You can just use a plastic polish on the clay and it will give you more of a satin finish. I've done polymer with and without the CA and both approaches seem to wear just fine. The big pro about wrapping tubes, aside from the obvious issue you noted, is that it is the only way to really do millifiore and other canes with some design integrity. And yes working the clay by hand will soften it, but I agree the pasta machine approach is easier.

What's that" I tried a simple two color swirl using some local FB team colors, and then I did a Makume style pen just roling a thin layer in 3 colors. Then, rolled all 3 colors on top of eachother. Then cut that in half and piled the layers on top of eachother, and rolled that together. I repeated many times, and ther rolled the whole thing up into a stick. That last part didn't adhere too well with the clay, so I'll have to figure something out....
 

PaulD

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What's that" ...

Millifiori mean thousand flowers and it refers to making canes of stacked clay and slicing them to make thin flowers or other creations. Here are some of mine as examples.

DSC_0004-3.jpg


DSC_0001-1.jpg
 

PaulD

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What's that" I tried a simple two color swirl using some local FB team colors, and then I did a Makume style pen just roling a thin layer in 3 colors. Then, rolled all 3 colors on top of eachother. ....

Oh and here is one of my mokume ganes. This one uses ink painted on top of layers of translucent clay with gold leaf. You can really do nice things with polymer clay

DSC_004.jpg
 

nava1uni

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If you make your pattern in a sheet, then you can roll it around the blank and it cooks much easier, less time, less wasted material. You can do lots of designs, etc.
 
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