Below, cutting the teeth away from the rubber jawset as neatly and carefully as possible, and then cutting holes through the entire thickness of the piece. Then, inserting it back into the original mold. The idea is to pour white resin into the mold for teeth, remove the blue part, and then pour pink resin for the gums. Below, the final product. Not too bad. (Tangent alert- the stuff that looks like pink slime is in fact pink slime. When resin is overloaded with colorant it will not cure properly. I was using Smooth-Cast 65D here, a white resin, and I had to put in too much colorant in order to get a color other than very pale pink. The saints at the Smooth On tech support department recommended I switch to a transparent resin, Color Match 325, which I did.) After I made a bunch more of these I decided this method may not be everything I hoped it would be. Sometimes pink resin would leak down over the white teeth and while I could carefully scrape it off before the resin set completely, this was something I'd rather not spend my time doing. Also, I would get thin spots or bubbles between the teeth and the gums at times, which would make for weak castings (I could crush in these spots with my fingers) which was definitely something I did not want. Time to try another method. Onwards!
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Some sort of two part mold would seem to be the answer, one for the teeth and the other for the gums. My first thought was to cut the teeth out of a resin jawset with my Dremel, insert them back into the original mold, and make a model of just the gums from which to make a second mold. Below, getting ready to pour silicone for the model.
Below, pink resin gums cast from these new molds, with teeth inserted temporarily. Looks pretty good but.... Damn. The round thing in the middle is leftover resin that cured in the mixing cup. See how nice and smooth it is? See how full of bubbles the gums are? There's lots and lots of things that cause bubbles in castings but here it's due to replicative failure. Each time I demold rubber from rubber, microscopic layers peel away from the surface, creating these bubbles in the mold. (Even if I'm using plenty of release. Which can also cause bubbles, damn!!) Three times I poured rubber into rubber to make these, adding more bubbles with every step. What to do next? Maybe at some point in the future I could investigate stronger rubber, but in the meantime, maybe I should go back to making molds from original sculpts whenever possible.
To date I've purchased teeth from other craftspeople to use in my masks, but I've always really wanted to make my own. Below, a pile of attempts made over the past couple of years, made with Monster Clay (a kind of plasticine), Super Sculpey and Apoxie Sculpt.(Skully is supervising. He is a very helpful skull.) A whole lotta nope right here. I finally settled on the Monster Clay for making the prototype teeth. I got tired of waiting for the other two to dry and/or set up in between sculpting sessions, and I got REALLY tired of trying to smooth out the hardened model with sandpaper or a Dremel. Monster Clay can be frozen to make it very hard and can be softened with a hairdryer or microwave or such to make it very soft, so it is adaptable for a variety of sculpting situations. It also smooths beautifully using rubbing alcohol or its more powerful big brother, isopropyl myristate.
Above, looking to see how the lower part of the jawset is shaping up when viewed from the side. The teeth are just loosely stuck down to the gums at this point, so I can easily move them around if I need to. And tada! Above, a finished Monster Clay plasticine model, ready for molding. Silly me, little did I realize that this would be the first of three finished jawsets I would mold. Sucks being a perfectionist. Above, beginning the molding process, and a tongue while I'm at it. The jawset has been firmly attached to a thin piece of plywood, which will serve as a mold board. Every little gap between the model and the mold board is filled in, as otherwise the mold rubber could find its way under the model, and float the model up on top of it while it's curing. Which would not make a very good mold at all. Above, getting ready to revise the jawset. Did I mention how I did this three times? Seriously though, it's easier to check the fit of the teeth in the head when they're in hard resin and not squishable clay. Above, a set of resin teeth that has been Dremelled down to fit the head better, and another set of clay teeth made by pouring melted Monster Clay into the mold, called a "borrowed casting". It's much easier to tweak the teeth from a borrowed casting than trying to make a whole new set from scratch. (If I wasn't such a chicken, I could have also resculpted my original set of clay teeth. But I wanted to keep them the way they were for extra insurance.) Above, revisions. To the right in both pictures is the original sculpt, still on the moldboard. In the middle is a modified resin casting, and to the left is the resculpted "borrowed casting". This first go round I removed the "flare" thingy from the bottom jaw, as it only really served to complicate fitting it into the resin head. I also made the plate for the upper jaw more symmetrical. You can see how the original sculpt has a bigger "bulge" on the left hand side than the right. Why did I do this, you may ask. Well, I was using a reject resin head casting to fit the teeth in, and I forgot that the resin on one side of the muzzle was much thicker than that on the other so.... in order to center the teeth in the opening, the plate had to be a lot wider on one side. Definitely not going to be the case with the average resin head! Fortunately I realized this before I got too much further into this process! A great big duh, but could have been a much bigger duh. Above, showing all three sets of revised teeth. The top set is the first one, the middle is the second and the set on the bottom is the final version. Besides changing the "plate" as described earlier, I did a lot of playing with the front incisors. I refined them in the second set but then realized I had also made the top ones too small, so I made them bigger in the third set. After re-checking my reference pictures of real wolves I also decided the gum area above the front incisors also needed to be longer, so I also changed that in the third set. I also did a lot of fiddling with the area circled in yellow in the right hand picture, with the way those particular teeth came together. The top incisor right next to the large bottom canine also underwent a fair bit of refinement. And since I had spent so much time fiddling with the teeth, I decided to fiddle with the mold making method as well. At the suggestion of an acquaintance I made my next set of mold boxes out of Legos instead of Tupperware containers, so I could get the mold boxes precisely the size I needed them and save molding rubber. Molding rubber is expensive. They don't call it "platinum cure silicone" for nothing. (A good source of cheap used Legos is bricklink.com.)
Above, the nose and tongue models with their squishy rubber counterparts. Wheee!!! Checking out the fit of the rubber nose in a resin head. Lookin' good! The resin head on the right wants a rubber nose too. And above, a pile o' puppy parts, ready for maskmaking!! I'm feeling good about the results of my endeavors here. Time to think about colors for fur!!
So I decided I was done experimenting with new ways of painting eyes and was ready to buckle down and concentrate on getting some good bubble free castings to paint. In theory it looked simple: make sure Part A is comfortably warm to the touch, microwaving if necessary; gently mixing the proper amounts of Part A and Part B together; letting them rest a preordained time in their mixing cup, then scooping off the bubbles which should have obediently risen to the top; pouring the mix gently down one side of the mold to minimize new bubbles; and then checking the casting once or twice during the first twenty minutes of setting to pop any more bubbles that dutifully would come to the surface. First mistake: not getting part A warm enough, so that the mix would be too thick for any bubbles formed while stirring to rise up and pop. If Part A was too cold, bubbles were also more likely to form while stirring in the first place. Second mistake: getting part A too warm. The mix would be beautifully bubble free in the mixing cup, but new bubbles would form no matter how gently I poured down one side of the mold and then the mix would set too fast to allow these bubbles to rise up to the top and pop. Third mistake: mixing the part A and part B as little as possible, so that there would be no bubbles but there would also be unmixed spots in the casting. These would not cure but would remain soft and sticky no matter what. At first the owner of Little Windows was a huge help and spent much time by phone and email helping me work out my problems. Her first suggestion was to let the mix stand in the cup as long as necessary for the bubbles to rise to the top before pouring into the mold. This, unfortunately, never happened. Her next suggestion was to adjust the microwave in increments of seconds to see what time worked best for getting the right temperature, but unfortunately my ancient microwave does not have this capability. Her next suggestion was to wipe down my mold with rubbing alcohol or acetone so that bubbles would not stick to its surface and rise more easily after the resin was poured. Unfortunately I found the only thing this did was introduce yet another opportunity to get lint in the mold. She felt bad that I had used up an entire kit without getting a single bubble free casting and sent me a new replacement kit free of charge. Then, she stopped returning my calls and emails.
However...I had piles and piles of bubbly castings, so I decided to keep the ones that had cured properly and use them later to try out new eye painting ideas. I put them all in a plastic baggie and set them on a shelf... and a month later, they had all yellowed. So that, ladies and gentlemen, was the end of that.
I briefly considered making eyes out of other kinds of resin, but rumor has it that Easy Cast, another commonly used resin, is hit or miss in the curing department and also yellows over time, and Smooth On's Crystal Clear- what Dreamvision Creations uses for its eyes- is somewhat toxic and as such is not suitable for a home studio. (Plus, when I asked about it, they told me they also use a vacuum chamber to make sure the castings come out bubble free!) When I called Smooth On's excellent tech department to ask what clear casting resin would be suitable to use in a home environment, they recommended Epoxacast 690, with the caveat that the two parts were fussy to mix and I would need a scale that could measure down to 1/100 of a gram. If I do go back to trying to cast my own eyes, this will be the material I start with. However I decided I had spent enough time chasing this rabbit down the hole and I needed to get back to what I was most interested in in the first place: making masks. I write my tale of woe here so that either a) you my dear reader can either learn from my mistakes and perhaps achieve a bubble free casting where I could not or b) save yourself a lot of time, money and aggravation and proceed directly to Etsy to buy a pair of blank bubble free resin eyes to paint for yourself. Which is what I ultimately wound up doing. I feel like a traitor. After all these years of casting in paper mache, I am seriously considering switching to resin.
I confess, I have no love of paper mache as a thing in and of itself, although I have come to appreciate its many qualities- strength, light weight, safety, low cost, and a long and interesting history. When I started out maskmaking I investigated many material possibilities but found none could match the qualities of paper mache.(Check out my earlier blog for the gory details.) The downside of paper mache, however, is how long it takes to cast anything with it- up to a week for one of my larger masks. That's a lot of time not spent sculpting or painting. Either a lot of things have changed or I've been living under a rock for the past eight years, but when I discovered fursuiting (and just how far ahead of me the furries were materials wise) I learned of a new material, Smooth-Cast 65D, that could be slushed into molds to make masks. Instead of taking a week, I could cast a mask in.... fifteen minutes. Above are pics of my first couple of attempts, using the silicone mold I made in my last post. Some finer points I learned during my experiments: The temperature makes a *huge* difference in how fast the material sets up. My first couple of attempts were done on a sunny porch on an 80+ degree day, and the material set up way too fast, as in I was happily slushing along, turning the mold this way and that, and the resin just set instantly in a huge gloppy wave in the middle of the mask's forehead or someplace equally inconvenient. The instructions say to cast at about 75 degrees F, and they mean it. It's OK to use a plastic spoon to help distribute the material around the mold for the first few minutes after it is poured in, but the spoon should be set aside once the material sets up enough to start to stick to it. Otherwise the curing resin may grab onto the spoon more tightly than to previous layers of resin, which can cause the new layer to delaminate. It really makes a difference to measure out Part A and Part B in two cups and then to use a third cup to mix them together. Otherwise, the mix ratio can be thrown off by material left behind on the inside of the cup that was poured from and/or extra material inside the cup that was mixed in, and result in an improperly cured cast, one which is very sticky and gooey with uncured leftover material. I found this out the hard way on my second cast. I was able to salvage it somewhat after a call to the Smooth-On tech department and much cleaning and scrubbing with rubbing alcohol, but it would still be something I would not want to sell. I have to say, I'm struck by how *similar* the resin and the paper mache masks look like each other (at least from the outside) when they are finished- same color, same weight, same feel. They even warp the same way if they're not cast thick enough. I'm looking forward to learning what other experiments will bring. |
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