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HOW TO CAST RESIN COPIES OF 1/6TH SCALE HEADS
(and keep all the original articulation!)
by Rob Sorrels
Sculptors put in lots of time and effort in making their sculptures. Please do not use these techniques to steal their work. Selling copies of someone else's work is STEALING, plain and simple. My intent for this article to show you how you can create different heads for your own use. If you want to sell 1/6th scale heads, please sculpt an original work and don't steal someone else's.
TOOLS, EQUIPMENT, AND STUFF REQUIRED:
1. MAKING THE MOLD Safety equipment (glasses, mask, rubber gloves, etc), Disposable paint brushes, Liquid latex rubber, GI Joe head, Cardboard, Glue (Superglue, Elmers, etc), Baby powder.
2. MAKING THE RESIN COPY
Safety equipment (glasses, mask, rubber gloves, etc), Mixing cups (I use measuring cups for this), Popsicle-type sticks, Toothpicks (sometimes), Resin & catalyst.
3. FINISHING THE RESIN COPY
Safety equipment (glasses, mask, rubber gloves, etc), Hobby knives (X-acto or equivalent), Rotary tool (Dremel or equivalent) with selection of bits, drills, etc., Sandpaper, A template with a bunch of different size round holes in it (office supply store should have them), Rubber O-ring (Size #91 - 11/16x7/16x1/8 for males heads), Wire, Acrylic paints, Clear (matt, semi-gloss, or flat) spray paint or lacquer.
Before getting into the "meat" of this article, let me caution you that some of these procedures, equipment, materials, etc can be dangerous if you don't use caution. PLEASE be careful, use safety equipment, and think about what you are doing before you do it. This should be fun, and a trip to the emergency room is never fun!!!
I. MAKING THE MOLD:
1. Take the head (that you want to copy) off the body. Usually you can just twist and pull and it will come off. You may need to warm it up to make the plastic a little more pliable. Marx heads can be removed by first removing the spring holding the arms to the body. The Marx head will slide out after you remove that spring.
2. Using your glue (I like to use gap-filling superglues), glue the head neck-down to your cardboard. I like the cardboard to be about 6" square so I can pick it up easily as I work with it. To duplicate Marx heads you will need to cut a hole in the cardboard for the neck to fit down into since the Marx necks are about 2" long! I use electrical tape on the bottom of the cardboard to hold Marx heads to the cardboard.
3. After the glue dries, start painting on the liquid latex with your disposable brush. Make the first coat thin and make sure you get the latex into all the little nooks & crannies like the nose, ears, eyes, etc. Be sure to cover the entire head and paint out onto the cardboard into a circle about one to two inches around the base of the neck. Let this first coat dry for at least a half-hour. Throw away the disposable paint brush, it's too much trouble to attempt to clean out the latex!
4. Keep applying thin coats to the head and the area around the base of the neck. Try to get even coverage over the entire piece. Allow at least a half-hour between coats so the latex has a chance to dry. Setting the piece in front of a fan will help speed-up the drying process!
5. Apply about a dozen coats to the mold-to-be. After the last coat, allow the mold to dry for at least 24 hours.
6. After letting the mold dry/cure for at least 24 hours, dust it well with baby powder. This will keep the latex from sticking to itself as you take it off the head.
7. Carefully peel the latex away from the cardboard around the edge of the mold. Peel it away up to the head all around. Dust the freshly exposed latex with baby powder.
8. Now firmly grasp the base of the mold with both hands, put a thumb on the top of the head, and peel the mold off the head. Pull on the base of the mold as you push with your thumb. Allow the mold to turn inside out as you take the head out of it.
9. Dust the inside of the mold with baby powder. Turn the mold right-side out. The mold is complete at this point.
10. To make the mold tougher you can bake it in your oven, but I've never felt the need to do this. As you cast the resin copies, the resin curing will generate heat and cure the latex so that it'll get tougher over time. Eventually the mold will rip, tear, or just generally break down to the point you'll need to make another one. Some of my molds have broken down after only six copies and others are still in good condition after almost 20 copies.
11. To make a cardboard support for the mold, take two pieces of cardboard that are about 6" square and cut a "U" shaped cutout in one side of each but smaller than the circular base of latex. Also make the "U" channels long enough so that when you slide them together around the neck of the mold, they overlap a bit. When we turn the mold upside down to pour in the resin, the mold will rest on these pieces of cardboard. I use clothespins to keep the cardboard pieces together where they overlap.
II. MAKING THE RESIN COPY.
1. Put the cardboard supports around the mold. Place the mold, head down, on a cup, mug, or other suitable (and sturdy) holder.
2. Mix the resin per the instructions that came with it. Use a popsicle stick to mix the resin in an appropriate size mixing cup.
3. Pour resin into the mold until it is about half full. Turn and rotate the mold to get the resin in all the ears, nose, etc. Take the popsicle stick that you mixed the resin with and poke it around in the mold to break up any air bubbles in the nooks and crannies. Don't poke so hard you bust the mold, just enough to get the resin into all the small spaces. The usual places air bubbles appear are on the ears, nose, and chin. Finish filling the mold with resin. Poke around (massage!) the ears, nose, etc to get all the bubbles out.
4. Let the resin cure for about a half-hour or so. The mold will be warm due to the chemical reaction of the resin.
5. Remove the resin duplicate from the mold in the same manner as you removed the original head. If you attempt to do this too soon, the resin will distort. If you do this after the mold cools down, you'll have a greater risk of tearing the mold. After practice you'll figure out a good time interval to allow before pulling off the mold.
6. Let the resin copy continue to cure. I usually let mine cure overnight. Put it on a piece of cardboard, newspaper, etc to cure.
7. The first copy from a new mold is usually trash. The baby powder that you use to keep the latex from sticking to itself is picked up by the resin and ruins the finish of the first duplicate. I just plan on tossing the first head into the trash. The heat from that first copy cures the latex enough so that it doesn't stick to itself as readily as fresh latex does.
8. Let the mold cool completely between casting copies. It will last longer that way. Remember, the heat toughens the latex.
9. I use cheap plastic mixing cups to mix my resin in, and popsicle sticks to mix it. After pouring the resin into the mold, I just let the excess resin cure in the mixing cup. Once it hardens, you can flex the mixing cup and the excess, now-cured, resin will pop right out. You can also leave the popsicle stick in the excess resin and use it as a lever to help get the cured stuff out of the mixing cup. If you wait for the resin to cure, clean up will be a breeze!
10. If you have too much resin left over from one head mold, and you don't want to waste it, you can pour it into another mold and leave it there. Later when you have more resin left over, you can pour it into the same mold, on top of the previous resin (now cured). A nice property of resin is it will stick to itself so well you'll think it was poured at one time. I had my router grab a head I was working on and it pulled the head out of my hand, spun it around a few hundred times and threw it across the room. It ricocheted all around the hard floor and concrete block walls. It turned out to be a head that I had poured from two different resin batches like described above. No damage at all to the head! (This also illustrates why safety gear is required!)
III. FINISHING THE RESIN COPY.
(NOTE: mounting technique applicable to HOF and CC Joes and 21st Century figures, others will require different techniques!!!)
1. If you use the same type resin I do, finishing the copy is fairly easy. The resin works just like styrene plastic. Start by sanding the base of the neck flat. Place a sheet of medium or course sandpaper on a flat surface, then just rub the copy back and forth until the base is flat and at the height you want it to be.
2. If you're making copies of old Marx heads, you'll need to use the sandpaper and/or hobby knife to clean up the mold line that Marx left on the heads. If you don't want to do this with every new copy, then use a cleaned-up copy as a new master and make a mold from it.
3. Take the template with all the round holes in it and find the hole that is just a tiny bit larger than the mounting peg you will be mounting the head onto. Place that hole over the bottom of the neck and center it up. Use a pen or pencil and draw that circle on the bottom of the neck.
4. Take your Dremel tool and using a drill bit, drill a series of small holes around the inside of the circle you drew on the bottom of the neck. Make the drill holes longer than the height of the body's mounting peg.
5. Put a barrel-shaped router bit on the Dremel tool and use it to router out the neck and head to the diameter of the drawn circle. Make sure the hole is deeper than the mounting peg is tall. The head should fit loosely over the neck peg at this point.
6. About 1/8th inch from the base of the neck, router a slightly deeper edge around the inside of the hole you made in step 5. A cone-shaped bit is best for this. This slightly deeper portion is where the rubber O-ring will eventually sit. The inside of the neck should look something like this:
7. Put a rubber O-ring on the body's neck mounting peg.
8. Wrap a small piece of wire around the mounting peg, above the O-ring. The idea behind these last two steps is that the O-ring will fit into the small groove we made in step 6 and hold the head onto the mounting peg. The O-ring's inside diameter is larger than the peg's diameter so it allows the head to flop around on the neck. The wire wrapped above the O-ring keeps the O-ring down tight on the bottom of the mounting peg and keeps the head snug so it won't flop around. The O- ring mounting allows the head to turn side-toside just like the original. Some folks cast the heads directly to the body, but that eliminates the articulation.
9. Test fit the head to the body. Make any adjustments necessary to get the head to fit snugly onto the body. Then remove the head for final finishing.
10. Wash the head well with dish soap. This will get your finger oils off the head and help the paint to stick better.
11. Paint the head with acrylics.
12. Allow the acrylics to dry well, then spray the entire head with clear spray paint.
13. Allow the spray paint to dry well (usually overnight) and then mount the head back onto the body.
14. Dress your new troop and enjoy!
MISCELLANEOUS RAMBLINGS ON RESIN CASTING
1. I use resin from Ace Resin, 7481 E. 30th Street, Tucson, AZ 85710-6338 website: http:\\www.crystaltower.com/aceresin Like I said earlier, this is easily workable with hobby tools. If I want to make several duplicates with changes to the original head, like removing scars, mustaches, etc, I make a mold of the original, then cast a good copy. I take that copy and make any changes to it that I want, then use it to make another mold for the changed head. I can now use that mold to cast a bunch of heads different from the original. Some of the ones I've made are: Sgt Savage without the bandaid on his forehead, Roadblock without his beard & goatee, Marx Silver Knight without goatee, and the CC "blockhead" and GI Jane head sculpt without hair (bald).
2. Don't put any unfinished resin parts on your furniture. I did one time... when I picked it up again a few hours later, the furniture's finish came up with the head... down to the bare wood... my wife loved that... :-(
3. The resin takes about 3 - 5 minutes to begin to set up. You have about that amount of time to get all the air bubbles out of the mold. If you wind up with a bubble, when you take the copy out of the mold it will have a hole in it where the bubble was. You can fill this hole with model putty or even auto body putty if you want to save the head. A tip I learned from another custom head maker - as the resin cures and gets slightly firm you can push on the mold to create a different look in the finished product.
4. Ace also sells RTV mold-making material. This is a two-part liquid rubber material that you mix together and then pour over your item (in a suitable box to contain the mess!) to make a mold. I haven't had much luck making molds with this stuff, and it's many times more expensive than the brush-on latex! I get my latex from Hobby Lobby and it costs about $10 for enough to make approximately 25 - 30 head molds.
5. The cheapest brushes I've been able to find for mold-making are the ones with plastic handles that you can find in hobby stores. I found a great source called "Everything's a Dollar" where I get a pack of 24 brushes for $1.00. That's enough for two head molds. Hobby Lobby also has brushes like this, but they get a few more cents for theirs. I also got my cheapo measuring cups that I use to mix the resin in from Everything's a Dollar. Hobby Lobby sells popsicle sticks in a box big enough to last you for several years, or you can get them in small sizes, too. You can also save them from your popsicles and/or fudgesicles! ;-)
