I do fine art equine sculpture in ceramics.  Finely ball milled earthenware with talc, porcelain, as well as English fine bone china.  I sculpt, mold, cast in studio, but the bulk of my work the past almost 25 years now has been custom glazing bisques sculpted by other artists.  Sometimes I kiln repair very rare, sought after pieces, and sometimes I get permission to resculpt and customize them into whole new collaborations.  It is kind of a unique niche for me that I inhabit, though others also sculpt, cast, or glaze such pieces - they just don't kiln repair or resculpt them past the greenware stage like I do.  So I thought I would post a few photos of some examples & how I do it so you can try it too!

Here is an extremely delicate sculpture called 'Dante' that was sculpted by Sarah Minkiewicz-Breunig & produced in fine art grade earthenware ceramic by Pour Horse Pottery, Joanie Berkowicz.   VERY few of these were produced and most were glazed by Joanie herself, but a few bisques were made available for other glaziers like me to finish.  This one came to me with two broken legs.  A client wanted me to kiln repair & glaze it for her.  Being a very rare and sought after piece, it was well worth the effort to restore it - if I could!   Dante stands about 4 inches tall.

To kiln repair a bisque (or even an already glazed piece) you need to use a bisque mender.  I used to use a commercially available product made by Coloramics years ago when I first started doing this back around 2006.  I'd been custom glazing ceramic horse pieces for about three years by that point.  Later when I could no longer obtain the bisque mender I had to learn to make my own because I could not find another product that worked nearly so well or cracked so little.  If you attempt this I suggest you try a commercially available bisque mender to start or ask me for my recipe if you want to try making your own!

First I rough up and 'score' the bisque just like piecing together slabs of wet clay.  I make it as toothy and grabby as possible so that the clay mender can interlock with the already fired ceramic.  I use a roto tool with diamond cutting discs, or you can use a diamond coated file to cut into the bisque by hand.  It doesn't matter if it's earthenware, porcelain, stoneware, or fine bone china.  Just be sure to wear suitable protection for your eyes & respiration.  I use a damp paper towel underneath the work so any dust settles onto it.  A damp sponge to wipe it up also works, you just don't want to breath the ceramic dust.

If the legs are thick enough I may drill them out and set in roughened kiln rods (Kanthal) before layering with bisque mender & clay.  I'll make a whole other post about that using an already glazed ceramic for that example.  Dante's legs were just too thin to benefit as drilling them out would likely have shattered them.

Making the ceramic as toothy and grippy as possible is the MOST important step, else the added clay may flake and pop off later.  I then 'glued' each piece back into place using the bisque mender and layered clay right over it.  Once it was at least leather hard or dry I could very CAREFULLY clean it up.  Very fragile and hard not to knock right back off!  If you knock off the leg just be patient and do it again.  I've used painter's tape to help support & turn the piece upside down so the leg can dry a upright as possible.

I had to sand & redetail the tendons on each leg before firing it to cone 04.  The toothy scoring allows the newly added clay to grip & interlock even if the co-efficiency rates between the materials are not a match, such as using earthenware to repair porcelain.  Some people use actual porcelain bisque mender to repair porcelain but taking an already fired bisque all the way back up to those temperatures has it's own issues when you no longer have the original props that were fired with it.  

When the newly added clay dries it cracks - so be patient and just fill in the cracks & smooth it again.  Bisque firing the ware will also make it shrink and crack AGAIN.  Don't freak out over it.  Just fill in the cracks with more bisque mender, sand & clean up the details, and bisque fire a second time.  Yes, it takes patience and tenacity.  If you didn't do a great job before it was bisque fired you can /still/ refine, sand, file, roto tool carve, add more bisque mender until you get it just right.  Do not be discouraged.  Just keep going!  This has taken me practice so trust me when I say my first attempts were imperfect.

Once it is all finally together and as good as you can get it, bisque fire him to cone 04.  Typically I have to fill in tiny cracks and fire twice.  Joanie has my profoundest respect that she could mold, cast, and glaze these at Pour Horse Pottery.

Here is the SAME Dante bisque that I posted before with the two broken legs - now all repaired in the kiln.  From here I could make him a custom base because he is a tippy, fragile little sculpture.  After under glazing & clear glazing I then proceeded to overglazing him with china paints and enamels.  My client couldn't have been more thrilled! 

I have to date kiln repaired three of this rare sculpture.  I consider myself highly fortunate with my progress, trial & error to learn how to restore these amazing pieces.  Over the past 20+ years I have been doing this kind of kiln work, I know of only one piece that cracked & flaked off a thin area later that wasn't scored & made toothy enough.  I think that's a pretty good track record BUT test, test, test so your clients don't get stuck with your screwups self destructing later!

You can see all three (soon to be four) Dantes I have custom glazed on my website under custom glazed ceramics.