EJR Beads

Author Topic: Cured Polymer  (Read 3425 times)

Benicia Iridescence

  • Newbie
  • *
  • Posts: 19
Cured Polymer
« on: July 06, 2015, 06:49:24 AM »
Hello and happy to be in your community! I am a Polynewbie and I would like to ask the members
how can I be sure that the pieces of Polymer I have baked are totally cured? I mean, is there a chance that they
haven't after having baked them for the appropriate time and at the right temperature?
Kind of a "test" so one can tell if it fully cured and strong?
Cities, like dreams, are made of desires and fears.
Italo Calvino

Peter

  • Hero Member
  • *****
  • Posts: 1586
  • Because together we got power
    • Mango Fizz Creations
Re: Cured Polymer
« Reply #1 on: July 06, 2015, 07:37:39 AM »
With round beads there is a definite timbre to them when I bounce them on my worktop. Buttons too now I come to think of it.

ejralph

  • Administrator
  • Hero Member
  • *****
  • Posts: 6030
  • They're not people, they're Hippies
    • EJR Beads
Re: Cured Polymer
« Reply #2 on: July 06, 2015, 08:12:10 AM »
You cannot really over bake the clay, so long as you keep to the right temperature and don't burn it.

So I advise always, get an oven thermometer, so you know the temp is accurate and don't be afraid to bake a little longer. I bake more of my beads for around an hour.

Also waste a little clay and make a test piece.  Roll it into a log pencil thin or a little thinner and bake it. After baking let it cool completely then try to destroy it! A strong clay like cernit or fimo professional will bend several times and show stress lines before snapping.

Beware though some brands are naturally weaker and even when correctly baked will snap more easily. It still gives you a good idea though and you can experiment with each baking to see if higher or lower temp gives better results

Emma
Emma from Sunny Sussex, UK
www.ejrbeads.co.uk Projects, articles, bead galleries & more
www.ejrbeads.co.uk/shop Art beads, clay & jewellery supplies

Benicia Iridescence

  • Newbie
  • *
  • Posts: 19
Re: Cured Polymer
« Reply #3 on: July 06, 2015, 03:29:07 PM »
Thank you very much Peter and Emma for your answers. I haven't really tried anything like you suggested, I have only tested them with my fingernails and judged by that the hardness of the material, I guess it's wise to be harder on a piece so one can be sure of the quality of the finished product.
Cities, like dreams, are made of desires and fears.
Italo Calvino

ejralph

  • Administrator
  • Hero Member
  • *****
  • Posts: 6030
  • They're not people, they're Hippies
    • EJR Beads
Re: Cured Polymer
« Reply #4 on: July 07, 2015, 09:28:05 AM »
it is worth investing  a small amount of clay just for experiments. Try to make thin sheets, logs etc - bake them and break them! You learn so much about the clay this way and learn its limits

Emma
Emma from Sunny Sussex, UK
www.ejrbeads.co.uk Projects, articles, bead galleries & more
www.ejrbeads.co.uk/shop Art beads, clay & jewellery supplies

CMcE

  • Newbie
  • *
  • Posts: 1
Re: Cured Polymer
« Reply #5 on: July 13, 2015, 02:58:55 PM »
Hi, I am new here too and enjoying all your wonderful advise.

Could I please ask a question regarding curing polymer too?  I have a toaster oven but the lowest setting temp wise is 180c .. do you think this is usable if I protect the clay or insulate it in some way?  Many thanks Carole x

MilleD

  • Hero Member
  • *****
  • Posts: 970
Re: Cured Polymer
« Reply #6 on: July 13, 2015, 08:00:02 PM »
Welcome to the forum CMcE.

I would suggest that is too high for polymer.  Even if you insulate the clay, there is no way of knowing what temp you will actually be curing at so could easily under cure or burn.

Do you have a normal domestic oven that goes lower?  Or even better (at least I think so) a halogen oven?

ejralph

  • Administrator
  • Hero Member
  • *****
  • Posts: 6030
  • They're not people, they're Hippies
    • EJR Beads
Re: Cured Polymer
« Reply #7 on: July 14, 2015, 02:50:15 AM »
I agree, it sounds like it would be hard to get the right temp.

But is the 180 the lowest marked setting? Or is it physically the lowest the dial will go?

Sometimes the dials are able to be turned lower, they just don't bother marking on lower temps because they are seldom used for food cooking.

So see if the dial will go lower, then purchase an oven thermometer and do some test bakings. You might find a place on the dial that works and holds a steady heat. Check and see how the heat changes over a period of at least half an hour. Does it rise and fall or does it stay stable? If the latter, you might be able to use it

I must admit though, since getting my little halogen oven, I've not looked back!

Emma
Emma from Sunny Sussex, UK
www.ejrbeads.co.uk Projects, articles, bead galleries & more
www.ejrbeads.co.uk/shop Art beads, clay & jewellery supplies