Cone 6 Porcelain Elaine's crystal

[Liz Hamann]

This porcelain is great to throw.  However, I 've been having a problem with the drying properties.  Attaching handles tends to be problematic.  I keep the pots under plastic until leather hard stage without signs of drying too much before the handles are attached. Once  the handle is attached to the piece, it's placed under plastic again.   Each day I check the pots to be sure the handles stay connected.     Inevitably the handles  begin to pull away from the pots.  3 or 4 out of 12 mugs or pitchers  will begin to really disconnect.    So frustrating.  I've tried vinegar and water, paper clay slip, just slip and still have the problem.   I'm about ready to give up on Elaine's.   

I do recycle the clay into slip, dry it, and pug it.

Previously I used Laguna/Miller 15 for many years.  I did not have the handle connection problem but always found hard specs in the clay that caused problems.  I think the hard spec problem is more tolerable at this point!  

Any suggestions are appreciated!

 Thank you,

Liz

 

[Min]

Is this the body Tom Coleman developed for his wife? If so might be worth hearing his take on handle attachment with his Coleman porcelain. About half way through this video he gives his thoughts on handle joining and drying when using porcelain. He uses plain water to join, have you tried that?

Welcome to the forum!

[neilestrick]

When it comes to porcelain, it doesn't really matter how slowly you dry them. If it's going to pop, it's going to pop. The issue is that porcelain shrinks a lot and has very poor plasticity and dry strength. So if the pot is leather hard and you're attaching a wet handle, then you're going to have issues regardless of how you're attaching them, because the handle has a lot of shrinking to do in comparison to the pot, and the attachment will be weak and pull apart because of the poor plasticity and dry strength. The best thing you can do is get the handle as close to the dryness of the pot as possible before attaching it. I prefer the look of a handle pulled directly on the mug, but with porcelain that's often not possible. So what I do is pull my handles on a bisqued mug, let it dry until it pops off easily, then let it dry on a bat until it's firm enough to handle without messing it up- still a little bit flexible. Then I attach the top to the mug, get the shape just right, and wait until it's almost firm before attaching the bottom. At that point I can put them in the kiln and speed dry them if necessary, because the pot and handle are already equalized. You don't necessarily have to go to this much trouble- it all depends on what type of handle you make. But you do need to let it dry a bunch before attaching it.

[Liz Hamann]

Thank you.  Yes, this is a Coleman clay.  I watched the video.  Never tried to put a handle on as shown, but I will.  Let you know what happens.  I hope the information about drying without plastic works ...  

Liz

[Liz Hamann]

Thank you, Neil, for the information.  I will try your suggestions...

Liz

[Min]

1 hour ago, Liz Hamann said:

I hope the information about drying without plastic works ...

That part did seem counterintuitive didn't it... not sure I would go that far.

[Liz Hamann]

Thank you for mentioning the drying.  I will be careful.

Liz