Making Slip Help
Posted 20 August 2010 - 11:01 AM
It's actually much easier that it reads to be when you do this on a small scale, and we are not making casting slip. You can dry out your trimmings and save them to use, or process some of your clay in a blender, with water, and judge the consistency by eye as you adjust. The sodium silicate is probably the hardest part.
I have also used casting slip I purchased in a one gallon jug. If you buy it, make sure it is for the firing Cone you use.
Posted 20 August 2010 - 11:23 AM
I agree with the above potters, to use the clay which you use to make your work. The advantages are that it is readily available, and will not present problems with shrinkage/fit.
I like to throw using a clay grogged with a 40 mesh mullite. I tried using it as a slip to brush over pots so that I would get a smoother surface to burnish. The grog presented a problem, as now seems obvious, it was never going to give me the smooth surface I wanted.
So I started to dry out my clay completely, slake it and then put the "slip" through a 100 mesh sieve, and I now get what I call "psuedo-sig," as it is so silky and smooth, and gives me a great surface.
So almost any clay can give you good slip, if you prep it right, I guess.
Posted 20 August 2010 - 04:03 PM
Posted 21 August 2010 - 10:28 AM
I crush the clay by putting it in a coffee can with 1-2" pieces of scrap steel pipe, then I shake it and roll it around for a while. I just keep adding dry clay as I take out the fine dust for screening. It is a little slow (but I'm in Uvalde, what else is there to do) the remaining clay dust if very fine. I have a set for each kind of clay I use. I recommend wearing a dust mask. Great tip using TSP- Thanks
Posted 21 August 2010 - 02:43 PM
Sieving after mixing also eliminates the need for multiple sieves; you just wash your sieve and you're set.