| After demolding your casting, you need to
lay it down on something. There are many choices here, plain unvarnished wood is a general
favorite. A piece of plaster board (drywall) is another. Finger foam is an excellent
choice, and pillow stuffing works great. I prefer finger foam these days, since it is not
likely to break the horse later, when it's dry and vulnerable. You can also use bubble
wrap with small bubbles, bubble side up so that air can circulate under the horse.
Now clean your mold. Here's a REALLY NIFTY FREE TIP... They make rubber "livers" to scrape the junk out of molds with, but I always lost mine and was always frustrated. Instead, you can take the lid of a margarine container, or similar, and cut a rounded off rectangle from it with scissors. You can actually cut several sizes, and make some with narrow ends, and have a whole batch free. They are so easy and cheap, if you lose them it's no biggie, and you can use them to clean under your fingernails as well! Now, see, isn't that nifty? Now, carefully scrape the wet clay from the inside edges of the mold. You can follow up by wiping with a clean towel, or if you're like me, your T-shirt. (I like the family to know how hard I've been working.) Put the mold back together, and of course you saved the pour hole casting, because you are very bright! Put it over by your horse, you will need it soon. (For those of you using molds that cast in sections, you probably can ignore this part. But sit quietly and don't disrupt the class. It won't take long.) When you are done cleaning the mold, strap or band it and put it aside. Now, take a little cup of slip and a little cup of water, and a medium sized brush for each. Grab an X-acto and your pour hole casting, (which we will now call Charlie, since I am tired of typing "pour hole casting") and eyeball the size of your horses pour hole. Cut a circle out of Charlie about the same shape and size as your horses hole, and if you are feeling really fancy you can bevel the edge. This is the plug. Test it against the hole in your horse, and trim it as necessary. It needs to fit snug. Now, remove it and put first water then slip around the inside of the hole. Put in the plug, and take your X-acto in hand. Press the flat of the X-acto blade against the plug, and draw it outward, so that you are pushing gently down and pulling outward, blending the edge of the plug into the horses belly. Follow this all the way around, and then scrape the X-acto lightly across the whole thing, smoothing it out better. You can also dip your finger into the water, and smooth the plug. At this moment, pause to thank your deity that you didn't do this at Hagen-Renaker for eight hours a day, seven days a week. You would be plugging pour holes in your sleep. Of course, you would be darned good at it. Maybe even win a prize at the company Christmas party. Now, you need to put another hole in your horse somewhere. Why? When you fire it, the air inside needs to escape. Actually , it won't blow up. Well, not EVERY time. (I know because several Owynns went through the bisque fire without holes!) But when you go to glaze them, the hot air will push through the porous bisque and make your glaze look like a tangerine's skin. If you plan on putting a stilt wire into the horse, make your hole accordingly. If not, you can make a smaller hole hidden up in the horses unmentionable area. This is the time to dab wet slip into any area of the horse that scraped in the mold. Look the casting over, and see if there are bits that need to be filled. You can fill them more easily now, than later when it is dry. You may want to just brush the area you plan to fill with water first, but if the horse is wet enough you don't need to. Now, throw Charlie into a jar or bucket or something. You can recycle all of your scrap clay, unless it has plaster, paint, or other stuff in it. I will tell you how to do this properly another time. Check your horses feet, and if you need to make sure that he stands up, do that carefully now. You may need to scrape the bottoms of the feet if there are seams. Just gently stand him up, and don't let go. When he is corrected, put him back down on his little bed and let him rest. He will need to be fully dry, that means several days at best, before you clean him. TROUBLESHOOTING Here's a few problems you may come across, and some likely solutions. Chill lines... these are horizontal lines that occur in a casting, going all the way across the body, or all the way across the legs. Looks like woodgrain, and can actually have separations between the layers. This is caused by pouring too slow, pouring slip that's too thick, or if it occurs in just one or two legs, the slip is not able to fill these legs quickly enough. In this case, you can actually make little sprues from the hoof to the outside of the mold, just enough so that air can escape more easily. Open your mold and decide which piece of the mold to operate on. Take an X-acto and just etch a line from the edge of the hoof to the edge of the mold. This little tiny tunnel only needs to be as thick as a little wire to start with. If this helps, but isn't enough, it's easy to make it wider later. Ears or detail not filling... slip too thick. One or more legs not completely cast... lumps. See, you should have strained it! Ears break off in mold... left the casting too long in the mold. Or, if the casting is still too wet to handle and the ears still break off, try spraying some water on the ear parts of the mold pieces just before you put it together and pour it. If the ear breaks off WHILE demolding see below. Things that break off or tear while demolding... there's some plaster that is holding the piece in the mold, so it won't release. Observe inside the mold where the "scrape" of clay debris is. You can take an X-acto and carefully remove some of the plaster that is sticking out and causing the problem. This may take several tries, but it's better to remove a little too much plaster and have your casting come out in one piece, and clean it up later in the dry stage. Areas on the casting that seem rough, and in the corresponding part of the mold some clay keeps sticking and it's shiny... this is usually from the mold soap having "sealed" this part of the plaster. You can carefully scrape away the skin of sealed plaster, down to the unsealed plaster. Be very careful, go very slowly. Hooves that get a dent or crease in their side... this is from the leg being thinner than the hoof, and inside the hoof the slip is not completely filled. See, the leg seals off first, and no more slip is coming into the hoof. The slip that's inside the hoof needs to shrink, but it can't pull air in so it has to collapse a little. If it's just happening once in a while, just fill in the dent after you cast it. If it happens a lot, you can actually make separate little pour holes for the offending hooves, and after pouring out your mold, you can remove the clay from the hoof pour hole, and re pour slip into it. This is tedious and aggravating, so only try it as a last resort. Mold that leaks, or has a lot of flashing... Flashing is an thin layer of slip that forms between two pieces of mold. You may be pouring your slip too thin, try going a little thicker. If it's just one piece, that piece may not fit properly. Clean it, check the fit, and if it still leaks then seal the outside with handbuilding clay before you start pouring. I can't think of any more now, so if you have any questions... send chocolate! Joanie
|
