Amy's Magic Slip for Porcelain. Cone 6-10 (Dry Material)
Description: The same great magic decorating slip I've had available for years. This is a porcelain slip, but it's not Coleman Porcelain. This has different feldspar and kaolin and melts at a slightly lower temperature. This also makes it great as a joining slip for slipping and scoring parts together. When you purchase Magic Slip in a dry formula you can also weigh it and add oxides and pigments to it.
Mixing: Add water to mix it as thick as possible like mud. Keep some of the dry material aside in case you add too much water to start with. Then, mix it with a drill and paddle. I use a 60 mesh bowl screen it once by pushing it thru by hand as thick as possible.
Application: As a thick slip it works best when you apply it to work that's just been thrown and ribbed. Do not cover the work with plastic to slow down it's drying! That's what makes it crack. You need to allow the water to evaporate off of the porcelain. Or, it sits and saturates the porcelain which is what causes it to crack. Just keep any breezes or drafts off of the work. Some people take a ware cart and cover the outside with plastic so it just keeps air off of the work, but the plastic isn't sitting directly on the work and the slip.
Apply as a thin coat dipped: This is when the slip is mixed to a 50 consistency on the hydrometer. When the pot is about leather-soft you can dip the pot quickly into the slip and let it set up.
Apply a thin coat as a spray: Mixed to the consistency of about 45 on the hydrometer you can spray a coat on the work that's bone dry. Let it dry, then bisque fire. We really recommend bisque firing all Real Porcelain to ONLY cone 010 so it's porous enough to absorb the glaze.
Compatibility: Porcelain Slip is compatible with a Porcelain body. The shrinkage is similar enough it sound work well. If the porcelain your using is made with a ball clay (instead of kaolin) it's not porcelain. Our other Magic Slip for B-mix and stonewares.
Firing: From cone 6-10.