Slip On Greenware

[GiselleNo5]

I loved using slip, but haven't in a while because I found it was a pain to set up. I think I bought some already made, but then had to sieve it, and it got funky fast. Is there a simple way to make/keep slip workable? (Sorry for the hijack, but thought this might be a question others have, too!) 

Nancy

 

I would say, just make it in smaller amounts. However you work with clay you can keep a reclaim bucket; drop the pieces you trim off in some water and let them soak for a couple days to become nice and mushy, then scoop some out and put in a jar or small bucket, then mix with a hand blender and add water till it's the consistency you like. You can make as much or as little as you want. I've had very good results with my slip that I make in this way. I make more at a time and put either vinegar or peroxide in it to keep the bacteria down. 

[nancylee]

Thanks, Giselle! That doesn't sound too overwhelming! I can do that, for sure!!!

Nancy

[nancylee]

Just another quick question: I don't remember what to use to color slips. Is it Mason stains? Thanks!!
Nancy

[oldlady]

carbonates, oxides and mason stains work.  you have to figure out how much.  cobalt can make all colors of blue from pale to dark depending on the amount.  some mason stains really are not effective unless using a large percentage.  

 

and, making slip is easier if you let your scraps dry totally, put them into a container and add water.  they will slake to a consistency you like at some point.  learning to judge the amount of water is part of theprocess.  it gets easier if you keep some dry scraps dry and add them if the slip seems too thin after you make it.

 

it really is fun to work with slip and slip made from your clay body is the very easiest to use.

[Rae Reich]

I use slip for a background over terracotta for illustrations...but, I recently discovered I can skip that step! Praise the kiln gods!

Was the little wood duck painted directly over the terra cotta clay?

[Rae Reich]

I forgot to 'follow' is thread when I posted my question - have just picked it up again.

All very logical responses, but matching the shrinkage rates and cones of both clays assumes these are all known factors! Need to do some research here - especially as the bag of porcelain was a 'freebie'.

Many thanks for all the above info!

You can just experiment a little with what you have, Celia. Make a tiny batch of slip from your unknown clays and apply it at different densities on a small form and fire it. If it shrinks and crackles (and if you don't want that) add some silica in the next test to make it flow. If it is clear-ish and flow-y, add some ball or China clay (kaolin) to stiffen it up. You should probably be scientific and take some notes and measurements as you go. You're likely to find a combo that works for your needs with what you have.

Rae

[Celia UK]

Thanks Rae - will try that. I'm not averse to a bit of trial and error, but recording what I do will be essential. I don't know about you, but I always think I'll remember - e.g. what that little container has in it (underglaze/slip/clay/earthenware/stoneware etc.) or the order of work I did for a test piece - few days later, can I remember ??? Rarely! It's an age thing