Help, Another Cracked Bead Problem that Needs Solving [Spotlight]

Polymer Clay Projects - Spotlight Series “I am hoping to find out what went wrong with these cracking Kato Clay beads.” ~Ritzs

Besides allowing you guys to display your accomplishments and share stories of inspiration, these “Spot” features can also be used for discussing problems that may come up with your polymer clay projects. My hope is for these “Show and Tell” features to help strengthen the community by creating opportunities for everyone to interact in meaningful ways.

Cracking Beads Issue from Ritzs

I am hoping to find out what went wrong with these cracking Kato Clay beads. I used Kato Pearl as I had a large block that needed using, and coated them with gold and silver powder. Cured them at 150c as it said on the packet, for one hour, and they have all cracked. I have never really liked Kato and I won’t buy it again. I also mixed a little Fimo Quick Mix with it. Please can you help?


So everyone… let’s get the problem solving started. If you need more information from Ritzs before you can provide some ideas for her to consider, be sure to ask. I can’t wait to see where this conversation goes. It will be fun to see what kind of suggestions you guys come up with.

If you are interested in sharing pictures of your polymer clay projects with the community, please follow these 2 simple steps:

1) Email several of your photos to me as attachments. My email address is shown in the “From” line of the weekly Polymer Clay Newsletter that gets sent out each and every Friday morning.

2) Include a description and/or story about your pieces, being sure to reference the tutorial(s) or blog article(s) that provided at least some level of inspiration for your work.

Don’t be shy. Everyone is VERY friendly here.

In the comment section below, please do compliment each other; Offer encouragement; Ask questions about the techniques used; And in general… be social. This is your community! It’s up to you to make it a fun and supportive place to hang out. All of you are amazing and it’s wonderful to have everyone here!

Cindy, the best thing about your site is the continuing support. If I try one of your techniques and have a problem with it, I can just ask questions here and I know they will be answered. Everyone’s so willing to share their experiences and advice and ideas. It’s awesome. :) ~Silverleaf

Cindy has brought us all together here as a family. This group of people are so wonderful and kind. I know there isn’t one of us that wouldn’t try our best to help in anyway we can. That is what this group is all about, should it be help with a clay problem or a personal problem everyone is there for each other. ~Peggy-B

** Did You Know… Members with current subscriptions to the weekly tutorial videos are always entitled to a 10% discount when purchasing 6 or more back issue packages in a single transaction. If you are interested, let me know which back issues you would like and I will send further instructions on how to complete your order.

Cindy Lietz SignaturePolymer Clay Tutor

  1. Sue F, 29 March, 2010

    From a Kato die-hard…

    My first thought is that the clay might not have been conditioned sufficiently. While it can take significantly longer than when conditioning other brands, Kato should condition to a firm but very pliable and resilient texture without any additives. I’ve found that to be the case even when the clay cut straight from the block is disastrously crumbly to start with. This is only a guess, but perhaps using an additive to soften the clay and supposedly “speed up” the conditioning actually resulted in it not being properly conditioned. I haven’t tried Fimo Mix Quick with Kato, although I do have a packet of it sitting in my workshop so I might give it a go. (I like Kato really firm, however, so I’d be unlikely to use Mix Quick with it for real unless I specifically needed soft clay for a particular technique.)

    I can say that on one occasion when I was experimenting with using a small amount of petroleum jelly to soften Kato — when deliberately overlaying hard patterns onto a soft base for the dimensional effect that results — the petroleum-jelly softened Kato did occasionally crack, although the same clay used on its own never did.

    I do think that people tend to under-condition Kato. I’ve seen plenty of comments about people conditioning it, then the next day going back and finding that they had to expend a lot of effort to condition the same clay all over again, which is not a problem I have. Once I’ve conditioned some Kato to my normal degree, it stays easily conditionable for weeks with just two or occasionally three passes through the pasta machine all that is needed to return to full plasticity. So again, if there’s a tendency to under-condition Kato, particularly if you’re used to another brand like Premo, maybe that happened here too.

    (NB: If the clay isn’t really thoroughly conditioned when forming your beads, you can sometimes help it a bit by working the beads a lot while shaping them, i.e. don’t just stop when they’re round, but keep rotating them between your hands for a time.)

    Also, how were the beads baked? Were they suspended on pins during baking (as in a bead baking rack or equivalent), or were they laid on crumpled kitchen paper towelling, polyester batting, or some other supporting surface, or something else? I now use polyester batting or crumpled kitchen paper towelling on a baking tray almost exclusively for roundish beads as pictured, as they don’t crack at all for me that way. In the past I’ve made beads where I baked some suspended on bead baking pins in a (home-made) bead baking rack, and others from the same batch on crumpled paper towelling, and some of the bead baking rack beads cracked slightly — nothing like the beads pictured above, however — while none of the beads from the same batch but baked on crumpled paper towelling cracked at all.

    Finally, since something pretty drastic must have happened to cause huge cracks like those pictured, it’s probably worthwhile noting that I don’t bake Kato sitting on or immersed in cornflour (cornstarch) because the resulting “cured” clay is extremely weak (maybe weak clay is why the cracks are like that). The one time I tried Kato immersed in cornflour, the “cured” clay was incredibly fragile and crumbly and could easily be broken with light to moderate finger pressure. This is a total contrast to Kato’s normal characteristics where it’s one of the strongest clays around, and I have seen another member post a similar comment about cornflour weakening Kato substantially in another thread on this blog. There were only a matter of seconds between putting this Kato test piece in the cornflour and putting it all in the oven so it wasn’t a problem with the plasticisers being leached before baking (although it might have been a super-leaching effect during baking; when I have time I’m going to test that all out properly). So in my opinion baking directly on/in cornflour (cornstarch) is another thing to be avoided with Kato if you want your finished items to be strong and well-behaved. Using some sort of barrier should be OK though, and other mediums like bicarbonate of soda (baking soda) might be OK although I haven’t tried them.

  2. Ritzs, 29 March, 2010

    Thank you Sue for your feedback I have to admit I am not a lover of Kato, I have only used Fimo or Premo in the past and maybe you are right about conditioning although I thought I had done it enough maybe I didn’t. I always bake round beads on polyester batting in fact most of my things are baked that way Well I still have half a block left the large one that is so I will give it one more try I hate to give up, so thank you again for your support. Ritz

  3. Bonnie, 29 March, 2010

    @Ritzs: I agree with Sue about the conditioning and sometimes Kato really shouldn’t be baked at that high of a temperature. It should be bake a little lower, longer. I took a class from Jana Roberts Benzon and she had us putting the Kato in a plastic bag and then putting it on the floor and using a mallet to pound on it to condition it . If your Kato clay was old, that could be the problem also. Jana told us to put liquid polymer clay on our canes to keep them soft and then wrap them in plastic wrap. We all had trouble with the Kato clay and did have cracking on some things because we didn’t condition some of the clay well enough. The worst was the black clay. We all trouble with the black clay and we all ordered our clay from the same place because we had to condition almost 2 pounds of clay. Three of us broke our pasta machines trying to condition the black clay. I kept adding liquid polymer clay to mine after I whacked it for quite a while and that helped. How old was your clay and did you leave it out?

    Put your beads back in the oven for about 5 minutes at 250 and then throw them in ice water while they are hot. We have done this at our guild when we had cracked beads. Don’t know if it will work on beads that have powder on them but it can’t hurt.

  4. Cindy Lietz, 29 March, 2010

    WOW! What helpful and insightful feedback you have all offered to Ritzs! Thank you so much everyone. Very impressive!!!

    @Sue F: I love your idea for disguising the cracks as though they meant to be there. Salvaging a ‘mistake’ can lead to the best ideas so thanks for suggesting that!

    @Bonnie: I have never heard of that trick before. That sounds neat!

    @Ritzs: Your sticky problem leads me to believe that the Mix Quick could be part of the issue. I look forward to hearing more about your testing on that.

    Cracking usually happens when one part expands or contracts and another part doesn’t. Though I haven’t worked with Kato myself, the under-conditioning theory that was suggested could be the case. If ingredients in the clay were not properly mixed , different areas could have baked at different rates.

    I was also wondering if the heavy mica coating had somehow baked at a different rate (either faster or slower) than the inside did, possibly causing the cracks.

    The only real way of solving this problem is more testing. Try all the suggestions and see what works best. Thanks for sharing this problem with us. It is always fun to figure out the solutions together!

  5. carolyn, 03 April, 2010

    @Ritzs: These have the look of the torn watercolor beads. Was there any similarity in the construction? That might give an idea as to what happened. Frankly, I rather like these. Just call them Picasso beads and you’d sell bushels!

  6. Carolyn Good, 29 March, 2010

    I use Kato clay almost exclusively but sometimes I mix it with Premo. I had problems with cracking for a while but discovered the same thing about having them suspended on a bead rack vs. laying on a soft “bed”. Donna Kato recommends Baking soda (not cornstarch) and I tried that for my larger beads and haven’t had a bead crack yet and they are still very strong.

    Only problem is that you can’t use this method if you have mica powders on them before baking as you have to wash the baking soda off after (I’m assuming that is what was on those beads?

    One other thing about conditioning Kato is that it only stays conditioned for a day or so and then you have to condition it again where other clays will stay conditioned for days and even weeks. (Can’t find Donna Kato’s link for this)

  7. Sue F, 29 March, 2010

    Hi Ritzs,

    It’s a shame your first batch cracked, because they look like they would have been lovely otherwise.

    I haven’t seen cracks like that before, so I’m figuratively scratching my head about what could have caused them.

    What did the clay feel like when you were working it? And are the beads really hard and strong but cracked, or are they brittle? Kato baked at 150C for an hour should be both hard and strong, so if they’re brittle instead (as possibly suggested by the cracks) then I’d guess that the composition of the clay has been affected. I don’t know whether that’s the Mix Quick, although I’ve read of it being used successfully with Kato, or whether something about the storage conditions of the clay, possibly before it even got to you, has adversely affected it (e.g. sitting somewhere hot enough to partially start the curing process, preventing it from binding together properly when you wanted to cure it for real).

    Maybe try it without any additives the next time? Or combined with some regular polymer clay instead of Mix Quick (e.g. a small amount of non-mica Kato if you have such, otherwise Premo or something else)? Being a born tinkerer I’d probably try all the combinations available to me based on the products I had on hand, comparing the behaviour to plain Pearl Kato too, just to try to figure it out…

    For conditioning, since you say Fimo is one of the other clays you’ve used in the past, based on an admittedly small amount of playing Fimo Classic in its conditioned state has a different feel to Kato in its conditioned state despite both being firm clays. Fully conditioned Fimo Classic feels and behaves to me like nearly-but-not-fully conditioned Kato. I’d say about 30 passes through the pasta machine at a medium to medium-fine setting (where clay conditions faster than at thick settings) is the minimum I ever condition even my best-behaved blocks of Kato. My crumbliest block of Kato at the moment happens to be an old large block of Pearl too, and it requires a lot more than that.

    (By the way, I’ve had a bit of a play with the new, tweaked Kato formula in the last few days. It is much easier to condition, as intended with the formula adjustment, and while I personally definitely prefer the older formula the new one is much better than I’d expected, and I think it will really please most people. Including anybody who got freaked out by the description in the previous paragraph of how much I condition my current Kato! ;D)

    For the cracked beads that you photographed, maybe you can “repurpose” them by deliberately playing up the cracks — e.g. using a crackling medium and paint to give a fine crackled finish to the rest of the surface that could be accented by the major cracks in the clay, or by back-filling the cracks with thick acrylic paint, rubbing a bit of paint over the rest of the bead surface and then rubbing most of it off again before it dries to give a cracked antiqued effect — or just use them as bead cores and cover them with uncured clay.

    And for the remaining uncured Kato, if all else fails maybe you can use it as the minor proportion when padding out your scrap clay, which is what I’ve started doing with the few blocks of Sculpey III I inherited from various sources (using a bit at a time with my mixed-brand scrap for making my own texture sheets).

    Good luck with your next try… I totally know what you mean about hating to give up!


  8. Maria, 29 March, 2010

    I agree with Sue F – from the pictures you sent, the beads look pretty cool as they are, as if you purposely made the cracks. Wondering if using something like TLS to patch the cracks would help?

  9. Ritzs, 29 March, 2010

    Hi all, thank you for the help, I store my clay in a plastic craft box with a clip closure i cant remember when i got the Kato but it would not have been more than a year i don’t think. the beads are very hard and i always dunk them in ice water as soon as they come out of the oven, i did wonder if this could have been what cracked them and i used pearl ex powder on them I will try them back in the oven as Bonnie suggested I no Kato is very crumbly but i felt it was quite soft after conditioning The strangest thing is the silver ones apart from the cracks are fine but the gold ones feel very slightly sticky and the gold has now changed to a not nice gold color I will try making more with the same clay but without the pearl ex and fimo quick mix let you no the outcome, But i would like to say thank you all so much for caring it means so much to no i can scream for help love to all the clayers

  10. Lisa Whitham, 29 March, 2010

    Ritz, although I use Kato – I’ve not had a problem with large cracks… I’ve had a hairline crack here and there, but that’s probably because I didn’t have my clay conditioned enough. Sorry I can’t help you with this…

    ~Lisa :)

  11. Bette L, 29 March, 2010

    It could be that you have a ‘bad’ batch of clay. We had cracking problems in one of our classes and the instructor talked to Donna Kato about it. It seems that there were occasional problems with some batches. The problem has been addressed by the company. Maybe you should try the new Kato when it is available in your area. It’s supposed to be easier to condition. I use mostly Premo! because of the conditioning problems with Kato.

  12. Ritzs, 30 March, 2010

    I will let you all no what happens I think i will try and save the silver beads by disguise, but the gold I will use for bead core, again thank;s to everyone

  13. Ritzs, 31 March, 2010

    Bonnie you suggested putting the beads back in the oven at 250 is that C or F I want to give it a go.

  14. Cindy Lietz, 31 March, 2010

    Thank you everyone for the great conversation going on here and all the supportive ideas! It is you guys that make this community all it has become.

    @Ritzs: Bonnie must have meant 250F because 250C would be way too high! 250C = 482F

  15. Nevena, 31 March, 2010

    Sue and Bonnie-Thank you very much for sharing your experience!I had a lot of trouble with my Cernit polymer clay-being very crumbly and hard to condition-i finally decided to replace it with Kato.I just bought some blocks,haven’t tried it yet but you are really saving me a lot of unsuccessful tries!
    Special thanks to Cindy for organizing and maintaining this supportive society!

  16. Ritzs, 01 April, 2010

    oops: thanks Cindy

  17. Ritzs, 01 April, 2010

    Well I have made some more beads with the same clay and wooppee no cracks, I also re-baked the cracked ones as Bonnie suggested but still the cracks are their so I think it had to be either the quickmix or the pearlex. maybe I will try both ways one with one and one with the other and see what happens.

  18. Christine Dumont, 01 April, 2010

    To prevent a big bead from cracking, Donna Kato recommends to sink it half-way into a bed of baking soda, cure it for half the required amount of time, then turn it over, sink it back into the baking soda and cure for the rest of the time.

  19. Phaedrakat, 01 April, 2010

    @Christine Dumont: Interesting tip, Christine — Thanks!

    @Ritzs: I’m so glad your beads didn’t crack his time! Hurray!

  20. Cindy Lietz, 01 April, 2010

    @Ritzs: YAY!!!! That is so awesome to hear! Isn’t it great to have such helpful friends! It would be great to find out which of the two (the Mix Quick or the Pearl Ex) were the offenders. Make sure to let us know after you have tested them out. So glad that your beads are now crack-free. Another problem solved!

    @Christine Dumont: I have not heard of that tip before. Thanks! Will have to try that sometime!

  21. Caroline, 02 April, 2010

    We were told at Ilkeston UK that if you press a cracked bead tightly together – using a cloth – as soon as it comes from the oven it sometimes heals…I had limited success with this though! HSome hairline cracks worked.
    With the large cracks you have maybe you could fill the whole void with a contrast colour and re-bake?

  22. Phaedrakat, 02 April, 2010

    @Caroline: Oooh, another great idea! A backfill kinda thing~ I like it!

    Happy Spring, everyone! Did you see the other day that Cindy mentioned PRIZES? At the end of the 1st paragraph of the “Crackled Ink Technique with a Side Dish of Mokume Gane” post, Cindy mentions that there will be prizes, something to do with spotlights & sending photos. I think there’s going to be another CONTEST! I’ve been asking a lot, but only because no one is answering…Cindy! ;0

  23. Cindy Lietz, 02 April, 2010

    @Phaedrakat: I’ve definitely been seeing your messages about my PRIZES reference… but have been holding off on responding to first see if anyone one else pipes up too.

    You are most certainly on track with your suspicion that another bead giveaway contest could be looming on the horizon. But with all your valiant efforts to draw attention to my subtle teaser line from the other day, it almost seems as if no else is interested in winning some more beads from me. Hmmm…

    Or maybe it’s just that everyone is out hunting for Easter Eggs on this fine Holiday Long Weekend. If anyone is curious about participating in another bead giveaway contest, you are welcome to speak up :-)

  24. Cheryl, 02 April, 2010

    Definitely interested in another bead giveaway. Would love your beads Cindy. Wondering which technique is next???

  25. Linda K., 02 April, 2010

    @ Cindy: I figured Kat was making enough commotion for all of us, LOL. I’d love to know what you’re planning!

  26. carolyn, 03 April, 2010

    @Linda K.: I agree … I was waiting for Cindy to weigh in on this. Of course I’m interested in another giveaway contest!

  27. Louise Traylor, 02 April, 2010

    I would be VERY interested…

  28. Silverleaf, 03 April, 2010

    Me too! I noticed, but figured you’d explain in your own time.

  29. Joyce M, 03 April, 2010

    Yes, yes, yes, another contest sounds great. I will be unable to participate the last of April through the 20th of May but other than that being an obstacle I vote Yes. Maybe I can just play catch-up if the time extends a little if you get started sooner. Willing but ??able?? Thanks for speaking up, Kat. I missed it, must have been speed reading lol.

  30. Cindy Lietz, 03 April, 2010

    What if I told you that the next bead giveaway event is actually, already happening… right under your nose’s. Wouldn’t that be kinda fun to find out about? Especially for those of you who are already entered and don’t even know it yet :-)

    Anyone care to speculate about what I might have up my sleeve this time? Surely some of you that have been around here for while should be able to figure out how my brain works by now. I’ll admit I’m a bit of a tease, but that’s just one of the quirky things that makes this community so darn fun to hang out at. At least that’s my opinion anyways… :-)

  31. carolyn, 03 April, 2010

    @Cindy Lietz from Polymer Clay Bead Giveaway: Bet it has something to do with commenting on the Spots …

  32. carolyn, 03 April, 2010

    … and, you know, guys, we really should be giving good critiques … it is great to hear the compliments, but we can all improve in one way or another. Study the posts rather than just first impressions. Let’s hear some ways to improve also. Cindy has this concept down pat … she always gives a compliment on what is good while at the same time telling us how we could do something better. If you only point out the ‘bad’ it would be discouraging, but if that is tempered with something ‘good’ then all is well.

  33. Debi S, 04 April, 2010

    I thought about the pearlex might cause some of the cracks on Ritzs beads, because the powder has a built in binder….could that cause parts of the bead with thicker applications to heat up and cool down too quickly? Just my penny. ;-)

  34. Cindy Lietz, 04 April, 2010

    @DebiS: Pearl Ex Doesn’t have a binder in it but Perfect Pearls does.

    Ritzs, did you use Pearl Ex or Perfect Pearls? Cause that could make a difference like DebiS mentioned.

  35. Susan B, 04 April, 2010

    I did spot the mention of “prizes” but was sure that Cindy would explain at some point and was willing to wait and YES I am interested in another competition. I too think it is to do with the great spotlight features and I agree with Carolyn that constructive criticism is always useful along with compliments of course!

  36. Susan B, 04 April, 2010

    p.s. @Caroline: I like your idea of filling the cracks with a contrast colour and rebaking — very clever!

  37. Ritzs, 04 April, 2010

    Hi Cindy i used Pearl ex

  38. Ken H., 04 April, 2010

    I would wager that the contest has something to do with the increased frequency of the “spotlight” sections. Noticed they were coming more frequently that in the past, but just thought you were catching up due to the overwhelming popularity of the “spot” segments.

  39. Phaedrakat, 04 April, 2010

    Yes, I think it has to do with the spotlights, as well — since that’s where Cindy’s mentioning the “and…there’s Prizes.” She’s done it several tmes now on spotlight pages. My guess is to enter you have to send in some pictures of your work for a spotlight article. And there’s probably some rule having to do with commenting as well. Hmmm, when will Cindy let us know for sure? (Don’t worry, Linda K., I won’t raise a commotion anymore!)

  40. Linda K., 05 April, 2010

    @ Phaedrakat: You are too funny!

  41. cherie, 05 April, 2010

    well,I’m all for a new contest! First one I could get in on–give us the details..we’re sitting on “pearls & lentils” here! lol –thanks Cindy, waiting to hear what ‘s up your sleeve now—

  42. Phaedrakat, 07 April, 2010

    @Cherie: Sitting on “pearls & lentils”? um…. ;D hehe

    @Linda: Whatcha mean, I’m funny? 8~O I wuz just sayin’! ;-D (my eye’s getting stuck from all this “winking”…)

  43. Sarah Young, 11 April, 2010

    Hi. I’ve been having the same problem with my sculpted beads. I bake them at fewer minutes than what the packaging of the clay states but still cracks are cracking. :(( Is it better to bake your beads longer in lower temperature or bake them faster in higher temps?

  44. Sarah Young, 11 April, 2010

    btw, I’m giving the baking soda a try. Would the baking soda be reusable?

  45. Christine Dumont, 11 April, 2010

    Hi Sarah – I have just baked, at 300F – 150C and for a 1.5 hour, a sculpted, barrel-shaped bead 3×2.5 cm using the baking soda technique I mentioned earlier. I sunk the bead more than half-way into the baking-soda and it came out perfect (as far as curing goes!). In some places the baking soda has gone brown in reaction to the high temperature. It’s better to bake at the stated temperature. Never bake for less time than stated.

    The baking soda is reusable. I have two trays – one is filled with baking soda, the other one is lined with polyester fiberfill – and cure in the one most appropriate for the task. I store the tray with the baking soda in a plastic bag when not in use.

    How do you build your bead? Do you take a sheet of clay, scrunch it up and roll it into a bead? Or do you create a bead from layers carefully pressed together? Trapped air is the surest way of getting cracks.

    A happy and crackfree day to all!


  46. carolyn, 11 April, 2010

    @Sarah Young: You can keep reusing the baking soda for PC baking.

  47. Sarah Young, 11 April, 2010

    Wow. :) thanks Carolyn. :) I’ll try that this weekend. :)

  48. Sarah Young, 12 April, 2010

    @Christine Dumont: Does it really take that long to bake it in baking soda? and if the baking soda turns brown, could you still use it or You’d have to discard it?

    I think the problem is with how I make the bead. thanks for pointing that out. :)

    Thanks a lot! :))

  49. Christine Dumont, 12 April, 2010

    @Sarah Young: It’s not because you are curing in baking soda that it takes this long, it’s because big beads take that long to cure while detailed work gains in strength when baked for longer periods. The baking soda in the tray won’t go brown – what I was referring to was bits of b.s. caught in the nooks and crannies of the bead. (I have sent Cindy a picture of the bead – it’ll all make sense when she posts it! :D)

  50. Cindy Lietz, 12 April, 2010

    Hi Christine and Sarah,

    Polymer Clay Projects

    Sorry for the delay. It’s been a busy day. Here is the pic.

  51. Christine Dumont, 12 April, 2010

    @Cindy Lietz from Ivy Leaf Charm and Olive Necklace: Thank you!

  52. Phaedrakat, 13 April, 2010

    Cool bead!

  53. Nevena, 28 April, 2010

    If I have to save the cracked beads for bead cores and cover them lately with a layer of clay or slices of a cane-do i have to use some liquid clay as an adhesive or the new slices will stick to the already baked bead during baking and for how long do you bake the covered bead?

  54. Phaedrakat, 28 April, 2010

    @Nevena: Hi Nevena, if you are completely covering your baked-clay cores, you do not have to use liquid, because you are “trapping” the core under the new layer of clay (or lots of slices.) But if you only use a few cane slices to decorate (not completely covering the old bead,) then you should add liquid clay to help them adhere to the baked clay properly.

    As far as baking, you need to bake long enough to cure the new layer of clay. Baking time depends how thick that layer is. You can cure the same way/time you normally do, as long as your oven isn’t too hot. (You can shorten the time a little if the layer of clay you added is thin.) The same rules apply — the clay has to be cured at the proper temperature for a minimum of 20 min (or whatever package directions say) per unit of thickness. Since ovens cycle up & down, it’s best to add extra time (usually double!) to make sure your oven is at the “proper temperature” for the right amount of time. Adding the extra time ensures that the clay gets to that “perfect” temperature for long enough to completely cure. Good luck, and don’t forget to email some pictures of your beads! Cindy can do a spotlight article on you, and you could win prizes… ;D

  55. Nevena, 07 May, 2010

    @Phaedrakat Hi ,agian! My cracked beads were also Kato -covered with translucent-exactly the coverage cracked.I baked at 150 (the pakage says so).I also added some liquid Kato as the clay was absolutely hard and dry and impossible to work with.Do you think adding too much liquid clay could cause the cracks?
    I am thinking of trying some Premo and Studio-could you please tell me on what teperature do you bake these 2 brands.I read what information i found in the blog-may be not everything. Have you ever thought of becoming a tutor?

  56. Phaedrakat, 08 May, 2010

    @Nevena: I’m not sure what you meant when you said, “My cracked beads were also Kato -covered with translucent-exactly the coverage cracked.” You used Kato clay, and covered it with translucent cane slices or something? Also, are you saying that only the translucent part cracked, or? Sorry, but there are so many ways to picture these kinds of problems!

    As for the liquid clay, I’m not sure whether it would cause cracks — I haven’t heard of that before, at least. I haven’t tried Kato clay yet (only the liquid,) so I’m not as familiar with baking it. I know it cures at a much hotter temperature. However, the liquid Kato is supposed to cure at 135C. If you mixed a lot of it into your Kato clay, the 150C oven might have been too hot & caused cracks. Perhaps a Kato user might have more to add on this subject!

    When you mix 2 different brands of clay, or clays with different temp ratings on the package, it’s best to use the lower number, and then bake for a longer amount of time. Most ovens cycle, getting really hot, cooling down, over & over. Going with the “low temp” for a “long time” works, because the oven doesn’t get too high & burn the “low temp” clay. It also works for the “high temp” clay. Baking longer gives the polymers plenty of time to bond during its periodic times at the proper temperature.

    Here’s the temp for most colors of Premo & Studio by Sculpey: they cure at 130C (275F.) If your oven tends to spike high, you can bake at a slightly lower temp & just bake longer.

    Thanks for your comment about “tutoring,” but I just enjoy helping around here sometimes. I have a bad back, and spend a lot of time in bed. My laptop is the only way to stay in touch with my clay sometimes! I’ve been working on a better work area, though, so I can leave my projects out whenever I want. That way when the pain gets bad, I can just cover my clay to keep dust away and head for bed. When I feel better, I can go right back to my work. As soon as it’s all ready, I’ll be doing a lot more “hands-on” claying. I can’t wait! As for actual tutoring, though, it would be impossible with my back the way it is right now. Someday in the future, perhaps — I do enjoy helping people! Thanks for that!

  57. Nevena, 09 May, 2010

    @Phaedrakat : Hi Kat! Thank you for your recommendation.The beads were made out of Kato-the bead cores,then i covered them with cane slices made of Kato translucent and Kato white-and just the cane slices coverage cracked-mainly where was the translucent.

    What is exactly this back problem ? Did you try homeopahty?

    You can be doing some tutoring on-line-as you do:)

    You also remind me -i sometimes don’t have time to bake my beads-the day i make them-what do you think-is it best to bake them the same day(to do ones best to bake them the same day) or if you have no time to do this,how long the beads can wait?

  58. Phaedrakat, 29 August, 2010

    @Nevena: Hi! I just saw this comment…must have overlooked it somehow. Very sorry about that… That’s a long time to wait for a reply, LOL! ;D

    You mentioned you like to wait to bake your beads. Even if they’re still waiting to go into the oven, it’s probably okay. It can differ, though, depending on the technique used, the type of clay, how you stored the beads, the temperature in the room, etc. [I left some beads in a plastic ziploc for a couple of years (Premo.) I had to ‘touch up’ the shape on a couple of them, but I baked them & they turned out fine.] One of our members who uses Kato always waits until her bead rack is full before baking her beads, so I know that it works fine to wait for a few weeks, at the very least!

    I don’t think there is an actual cut-off as to how long you can wait to bake. Your beads should be fine as long as they’re not left in prolonged contact with porous things*…that make the plasticizers leach out. *Things like: incompatible storage containers, paper, baking soda, cornstarch, the wrong type of plastic wrap, etc. Another example of ‘waiting’: old canes that are too dried-out to use on projects (or they got partially cured,) can be baked and turned into cane-slice beads. I did this with one of my first Fimo canes after several years — the beads came out fine & quite strong.

    I’m wondering if you ever figured out your original problem…the cane slices that cracked on the core bead? I went back and re-read this thread…there are so many great tips about Kato clay and cracking beads! It’s possible your cane slices cracked because the clay wasn’t completely conditioned…or maybe one of the clays was better conditioned or softer than the other (leaving parts to expand/contract at different rates…causing the cracks.) Or perhaps you’ve just moved on to lots of other fun, new projects!

    I’ll say no more…I’m wondering if you’re still a member…maybe just hanging around quietly? I hope so (not the quiet part, LOL,) but I haven’t seen one of your comments in awhile! I do hope that everything is well on your end…please leave a comment if you get a chance, so we all know you’re okay. Take care, and have a wonderful day! *big smile & a hug* ~Kat

  59. Nevena, 02 September, 2010

    Phaedrakat: Hi Kat!I saw your message yesterday late in the evening and tried to answer immediately but the pc erased the comment twice so i decided to try again today. I stopped dealing with clay from some time-it was a very hot summer here-past two weeks we had 40 degrees Celsius almost every day and the room where i can make my beads has no air conditioner so i thought it would be better to wait cooler days.Besides i need also to bake them.

    I am not a member but i have several of Cindy’s videos.In these months i had a lot of other work to do +some health problems and i was rarely checking the blog-just the pictures- but i saw lots of beautiful pieces-complimetns to the authors!

    About Kato beads-i decided to leave Kato polyclay (the testing) as i don’t like the odour of this material and also i receive some kind of a skin reaction when working with it.I have gloves but i don’t use them.

    A big smile and a hug to you also! and thanks for the advices!Hope you are feeling well too! N

  60. Cindy Lietz, 03 May, 2010


    Polymer Clay Projects

    Hello to Everyone,

    Some new Spotlight project pictures that relate to the topic of this page (Cracking Bead Problems), have just been added in another post. They were submitted by Cheryl-V. The link by my name will take you to where you can see them, along with a bit of a write up about some issues Cheryl was having with cracks forming in her heart shaped Chrysanthemum beads.

    BTW: Thanks to everyone above, who took the time to comment in this thread. Your feedback, support and fun conversations are always such a wonderful part of my day. Although I don’t get a chance to address everyone individually, please know that I do read everything. ~Cindy

  61. Nevena, 06 May, 2010

    Hi Phaedrakat! I did not get notification that you had responded me-although i had subscribed to this entry.I just thought i had to search this info somewhere else.I “passed by” and was pleasnatly surprised by your comment!

  62. Erika Davis, 21 November, 2011

    Seems this issue of cracking hasn’t gone away. I spend a great deal of time coditioning kato clay but it still cracks especially large beads made with the mica clays. I find the copper very dry and crumbly and very difficult to condition. I had to add a lot of liquid clay to get it to soften.

    Earlier today I rang one of the online clay stores to order some premo sculpey ( I won’t be using kato again) and the lady that runs the store said she had the same problem with kato clay and her students beads cracking.

  63. Nicole Nation, 18 June, 2014

    Hi Guys,

    I absolutely love watching your videos and just joined your newsletter!

    I am having SO much trouble with my beads cracking…..I am making necklaces with 8-9 beads on chain. The beads are approx. 20mm in diameter. Most of them were cracking so I tried to eliminate as many things as possible, it ended up being our thermostat in my kitchen oven. We have since had his replaced but still having the cracking issue!!! I have lost at least 100 clay balls!!! Unfortunately we don’t have shops like Michael’s in Australia so our clay is expensive :(

    I’m hoping that you can help me out with this one pretty please!



  64. Sue F, 19 June, 2014

    Hi Nicole,

    If you’re using a bead baking rack or have your beads suspended during curing, try sitting them on a bed of bicarbonate of soda or on a piece of polyester batting/fibrefill instead. Many years ago I compared these options after having more beads crack than I was happy with, and the cracking was almost entirely due to curing them suspended.

    I make lots of large beads — I made about 50 this week in the 25-35mm diameter range, and I use Kato much more often than I use Premo too, which the message above yours talks about — and don’t have any cracking at all unless I’m doing one of my mad scientist experiments and am mixing weird things into the clay, or putting something odd in the centre of the bead, or things like that.

    You could also try curing your bead cores first, and then covering them with your decorative clay layer and curing again. That’s what I do when I want to use different clays (or other materials) that I know expand differently while curing.

    Also, in case it’s relevant, clay softened with petroleum jelly or baby oil or products like that are much more prone to cracking than straight block clay.

    I hope that helps a bit,


  65. Cindy Lietz, 21 June, 2014

    Sue you are amazing! The detailed help that you have given Nicole is not only a great help to her, an excellent source of help for others, but also an enormous help to me! I am getting ‘buried alive’ with questions and help from knowledgeable members like you, makes all the difference in the world. Thank you from the bottom of my heart!

  66. Helen Mills, 27 June, 2014

    Hi everyone

    I have never used Kato clay but am not so keen to try after all your problems with cracked beads!

    I always make my large beads with a foil core – usually just rolling my used chocolate wrappers up into a firm ball or ‘log’ while watching TV. Very therapeutic! I cover them with a medium layer of scrap clay or white if I want to use translucent later and then partially pierce them in a few places before baking to allow any trapped air to escape.

    You can then remove any bumps with sandpaper before coating with liquid Sculpey or similar and re-covering with your chosen decorative sheet, cane slices or extruded ‘snakes’. I drill my beads after the second baking. (I use a fan oven and polyester batting in the base of foil roasting tins covered in more foil to cook my beads.)

    Hopefully those of you with Kato clay to use up might try this method but of course with all that foil in the middle you don’t get through too much clay. You do get lovely big lightweight beads though!

    Best wishes from Devon (UK), Helen x

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