Thanks!

Speedy Holiday Shipping!

Make sure to get your orders in so that we can assure your special gifts arrive on time. Dark-Platypus is shipping out orders daily during the holidays. We want all your favorite presents and items to be enjoyed this season.

Also, check out all the new products we have coming out at the show! All of these items will be available for purchase here on the website after the show, but if you happen to be going to the con, you can be among the first to get them there! Do stop by and see us at booth #1424 in the main Exhibit Hall!

Thanks!

-Andy

They will be premiering at Gen-Con this year, and then will be made available on the website August 9rd.

Dungeon Life Master Series Walls

“The Dungeon Life: Master Series presents brand new wall designs, beyond the basic dungeon wall. Add a little more 3D cool to your game with Sci-Fi, Tavern Walls, Cave Walls and more!”
Check them out here!

Magna-Tiles

“Let’s face it, monsters are always attacking from cliff-tops, assassins are striking from the rooftops, and there’s really no good way to illustrate that kind of elevation difference on the battlefield. Until now!”
Check them out here!

Magnetic Area of Effect Markers

“Easily determine blast radius’ and keep track of lasting zone effects.”
Check them out here!

Magnetic Stalagmites

“With their ability to make fluid shapes quickly and easily, Bendy Dungeon Walls really excel at making organic looking caves and caverns. To complete the effect, throw down a few of these stalagmites to both add atmosphere, and provide some cover for your monsters to hide behind.”
Check them out here!

Magical Light and Torch Sconces

“Clip ‘Em on your Bendy Walls to add some much-needed illumination (but not too much!)”
Check them out here and here!

Dungeon Clings

“This represents a cool new concept in portraying some of the more 2D elements that might be found on your game table…static clings! Just like when you were kid, but now for gamers! They work great on our Magna-Map or any laminated map.”
Check them out here!

As you can see there is a great variety of new stuff going up. Go ahead and take a look!

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All around the site, you’ll find the same great products that you are used to seeing from Dark-Platypus Studio. Not quite everything is back in place as of this writing, but the last few minor products should be filling in very soon.

And what’s around the corner? Why, NEW STUFF! With the new site, you can look forward to more frequent updates, and Cliff will be helping me make those updates happen (for my own self, updating the website was always on my list of things to do, but I never got to it because it was about my least favorite job), including listings for all the new product I’ve come up with since last year’s Gen Con. This year’s convention season is just around the corner, too, and I’m also coming up with all sorts of brand new stuff that you will see here first! Here’s a spoiler to whet your appetite: BENDY SCI-FI WALLS!!!

Okay, that’s enough hyping about me; now to hype some of my friends. First, hop on over to Arctos Comics and check out Cliff’s awesome webcomic, Orion the Hunter. When you’re caught up with that, head over to Hydra Miniatures and check out the impending release of Matt Beauchamp’s amazing new War Rocket miniatures! I did the casting work for some of these pulp-style sci-fi spaceships, and I think fans of the genre are going to be blown away!

I have been spincasting for a couple years now, but to date all of my molds have been made for me. Jeff Acker of Ackertech Castings has done all my mold-making, and has also been a font of knowledge on topics ranging from moldmaking and casting to Battlestar Galactica. Much of what I am doing here is based on advice Jeff gave me, at least as I remember it. I also gained some insight from the recent “How I make a Master Mold” article on themouldmaker.com. Further knowledge has been gleaned from the yahoo lists 1listsculpting and casting, and from Philip Romanoff’s extremely hard-to-read book, “The Art and Science of Centrifugal Casting.”

Step One: The Work

For my first mold, I am going to be trying a bunch of metal pieces I have lying around, with the hope that they’ll be easier, or at least if I mess up I won’t have to worry about ruining them. The items seen in PIC #1 include:

1. A locknut. This is the only thing I’m molding today that I really really need, and the main reason I am making the mold. These are needed in moldmaking to keep the two mold halves aligned, and it seems best if I were able to make my own. I salvaged several from some old retired molds I got from Jeff. Most I will use up on my first few molds, but this one I set aside, and polished up real nice, and he will be my new master locknut. From the mold I make today, I hope to spin up several of them, and then make a mold for them. That way all of my locknuts will be exactly identical should I ever need to replace one in a mold.
2. A 15mm zombie. I sculpted this a while back, and Jeff made the mold for me. I include it in this mold for fun and practice.
3. a 28mm “Sir Kned of Phlanders” and his shield/shield arm. Made from a gravity cast mold of the first sculpt I ever did. Not very detailed, not very good, but a good practice piece.
4. Two 3Df  Flexible Dungeons doors. These doors look similar but are made from different sculpts. These are casts from the mold that Jeff made for me for my Flexible Dungeons set. I think the doors are a bit thick, so I am hoping to use the compression effect of the moldmaking process to my advantage, to thin them up a bit. The casts made from this mold should be a bit thinner, which I can then use as masters to make a door production mold, and the casts from those pieces will be thinner yet…hopefully just right.
5. A Cylon. Sculpted as a personal project. He is extremely unlicensed, and hence, doesn’t exist. No, you can’t have one.
6. Two Gaming Tokens. Thrown in for the fun of it. These are current casts from my production molds, which means they are already two generations removed from the master. We’ll see if they get too thin to cast or what. I’m mainly curious about what happens to the size of the “image area”, the center flat area inside the filigree. Right now, it is just a tiny bit over ¾” in diameter. If they shink up just the right amount, they may get to exactly ¾”, which would be desirable, since my stock sticker size is exactly ¾”.
7. A badger. One of my early sculpts, made from a rtv spincast mold. The regular badger is a popular Summon Monster 1 (d20) critter, so it would be nice to have a spincast mold of these. We’ll see how this one turns out.
8. A boar. Another early sculpt, which was rtv spincast. Just thrown in for practice.
9. A Crystal Mephit. This is one of three pieces in the moldset that I am attempting that is not made entirely of metal. This guy is made of a green/brownstuff mix over a pewter armature (actually one of the aforementioned 15mm zombie miniatures). I include him for practice and fun, because I already gravity cast the mephits I need, and he was sculpted in about 10 minutes, so his value to me is very low if he does get damaged.
10. Spliffy, the Medium-sized Monstrous Scorpion, 28mm. This piece was sculpted in the new procreate putty, and was an animal companion for a druid in our Dragonmech game. I think the piece is durable enough to survive, and mostly flat, so he should be okay. I know I should stay away from putting any nice sculpts that could be damaged into this first mold attempt, but I just can’t help myself.
11. A blank Pendant. This piece is made from my original large token master, which was cast in resin from a cnc master Jeff made. It has a green-stuff sculpted filigree, and I’ve added a pewter neckstrap loop, attached with a little bit of Sinbad superglue and some procreate. The Sinbad glue, by the way, is supposed to be able to handle temps of up to a 1000 degrees, so should be fine in the vulcanizer. We’ll see.

Step Two: The Materials

I will be making today’s mold from a set of Contenti 700 series rubber, shown in PIC #2. The first thing I attempted to do was pop out the little center hole on the top piece. It didn’t come out real clean, and left lots of stringy rubber behind (PIC #3). I guess I should clean that up, so it’s time to move on to:

Step Three: The Tools

My initial selection of tools includes a couple knives, with Swan Morton #10 blades, a ruler, a cutting board, and some router blades (PIC #4). If I need anything else, I’ll take pictures of the new tools I bring in as I go.

Step Four: Let’s Play!

I’d like to get a feel for how the rubber cuts, delaminates, and tools in general, so I’m going to play for a bit on the little center plug. Once I’ve got that down, I’m going to try to clean up the mess I made in the center hole of the top disk.

Okay, success I guess. The material sure is a bit gummier/stickier/stringier than I expected. I think I’m getting the hang of it, but it will take some getting used to. Time to move on to the serious mold-making.

Step Five: Preparing the Mold Halves

The first thing I’m supposed to do is cut a couple big notches into the rubber to help me align the two mold halves while I’m working on them, so that’s what I do. Jeff has some big scissors that work real good for this apparently, but I don’t, so I just use my knife. Theoretically, these notches will fill back in when the rubber starts to flow when vulcanizing. Neat. I’m even supposed to cut out a couple more after I get everything else done.

Next, I will make a place for my central core to sit. Right now, I don’t have steel core, just one a made from pewter from one of the empty center spaces in one of Jeff’s molds. Since it is just pewter, and I don’t want it to deform under the pressure, I’m going to cut in a space for it. I measure to get it centered, then trace around it with the tip of a file to mark it in the rubber (see another tool! I knew I’d need more!).

I cut through the first two layers and peel them up without any problem. I decide to go down one more, but accidentally start to peal up two. D’oh! I managed to correct myself a little bit into the circle, and just kind of shoved and poked the extra peeled up bit back down onto the mold. I hope that’s okay. :/

Now to cut one layer out of the top. I place the core into the hole I cut…fits great. Then I put the top piece on, and align it using the notches I cut earlier. I then carefully flip the whole thing over, and remove the bottom piece…leaving the core sitting on the top part of the mold in the exact spot it needs to be. PIC #8. I trace it and cut out one layer as before.

Step Six: Placing the Pieces and Planning

Leaving the core in place on the bottom half, I now place all of my bits around it, and decide how they will be gated and vented. I mostly do all this in my head, but for your benefit I may go back and photoshop on my initital thoughts onto PIC #9.

Looks like the 4” diameter core I made was a bit too big for some of the pieces I chose, so Kned and the scorpion have to be tilted at more of an angle than I’d prefer. I have set them up pointed opposite the rotation of my spincaster, so the cavity will still go in the right direction for the metal flow…hopefully. We’ll see. Also, I didn’t want to get too crowded on the mold in case I need to cut more air vents, etc., so I leave off a couple of my initial choices. I leave out one of the gaming tokens, because 1 is plenty, and I leave out the boar, because his leg positions really make me think I will need to build up one side of the mold to make them work right, and Jeff suggested I stay away from build-ups on first time out (which seems very sensible—there are enough other things that can go wrong already). Oops, I also left out the Cyclon, because he fell on the floor and I forgot about him. Oh, well, some other time, toaster!

Step Seven: Cutting the Cavities

Now I trace out all the minis in the positions I’ve decided on (again using the tip of the file to ‘draw’ on the rubber—that works very well), and start to cut out the cavities in the bottom half of the mold. This will surely take some practice, so I’m going to start on the easy ones, and work my way around to the trickier pieces.

Okay, that’s done! Whew! Above is a pic of what the bottom mold half looks like with the figures in place. The material did in fact take some getting used to. Also, despite my best wishes, I did need to do a little build-up around the mephit’s ‘wings’. Hope it works okay.

Step Eight: The Top Half

Now to make the cavity holes on the top half of the mold. I’m a little foggy on this…it seems from the mouldmaker.com article that I could just press the mold now as is, without cutting top cavities, and just letting the heat and pressure do the work. On the other hand, maybe he just skipped showing me that step. Jeff says he does cut the top cavities as well, so that’s what I’m going to do today.

I will take the pieces and insert them into the mold bottom one at a time. With one piece in place, I will then place the top mold half into position, and then carefully flip the mold over. I will then remove the bottom mold half (now on top), and the piece should be sitting on the top half in the position I need it to be in (just like with the center core). I’ll cut out what I think needs cuttin’, and then fit the mold back together with piece inside to test it. Here goes!

IWell, that kind of worked. I think it’s good. Some of the flatter pieces didn’t get cut-outs on the top; I really don’t think they’ll need ‘em. There is one issue, though. The scorpion…I think he needs some build up around his little feet:

Therefore, I’m going to have to try using the lighter fluid as a solvent, and then sticking more rubber there in the proper shape. (I didn’t use the lighter fluid on the build up around the mephit, because I had already peeled up all the rubber in those little areas, and was working with only gooey stuff to gooey stuff. I think that will be okay, but if it doesn’t work, well the mephit I don’t care too much about. The scorpion I would really like to see turn out.). This means I’m going to have to go get some lighter fluid.

Okay, I went out to the store and got some of this stuff. It has Naptha in it, which is as I understand it, the solvent needed to make the rubber really stick to itself. You apply it to both pieces and it dissolves the rubber a little bit, and you can then stick the two pieces together, and they’ll stay.

As you can see here, I  tried it. And boy, howdy, it works. Good. I even managed to make not too big a mess of myself or my tools (because it also cleans up the black gunk it makes real good). I also managed to spill a little bit of it on the mold there, but managed to get it cleaned up, I think. Hope that doesn’t do anything bad…

Step Nine: Final Preassembly Steps

Now that all the pieces are cut in, I screw several locknuts in place, and cut a couple more little notches in the side.

Step 10: Talc the Mold

For this step I am using a talc bag which I made out of a bandana. I used liquid stitch (wonderful stuff) to make it into a rectangular bag, and affixed some Velcro to be able to open it and seal it back up. I have filled it up with some Mica Powder, which is apparently a really fine grade of separator, finer than traditional talc. I take all the minis out of the mold, bang it with the talc bag, and then put the minis back. I blow off any excess.

Not shown here is the little metal plug for the top hole of the mold. I made it the same way I made my metal core. Basically, I set one my Jeff-made molds top down onto the concrete floor, just the top part of it, and then poured metal into the top hole. I let it cool, and viola! Instant plug. I had to do it a couple times to get it at exactly the right height. I talc that too, and insert it into the hole in the mold top.

Lastly, I place both mold pieces together, aligning them the best I can (the mold lock nuts now get in the way a little bit), and manually squishing it down as good as I can.

Step 11: Preheat the Mold Frame

Next, I slide the mold frame into position in the vulcanizer, and work the pump by hand until it is closed. Then I insert the rod and give it a couple pumps, to get it up to about 1000 lbs of pressure. It doesn’t take as much work as I’d have thought to get it there. I watch the mold frame very closely as I am doing this to make sure the top part is sinking down into the ring like it is supposed to. It does, so everything appears to be seated correctly. I let it warm up at this pressure for 3 minutes before applying any more pressure.

Step 14: Now We’re Cookin’!

Jeff says 90 minutes at 310 degrees at 2500 pounds of pressure will do the job, so that’s what I do! Or, I should say, that’s what I attempt to do…

My first issue is that it took WAY less work to pressure up the jack than I thought it would. I was imagining just having to pump and pump to get to that kind of pressure (it sounds like a lot), but that turned out not to be the case. I gave it two good pumps, and overshot the mark…a lot. I ended up at nearly 4000 pounds. I didn’t know what to do about that, so I just left it.

I was working out in the garage doing some casting while it cooked, so I could kind of keep an eye on it. Twice during the process, once at about 45 minutes and again at about 65 minutes, the guage lost some pressure. It dropped down to about 2000 lbs both times. I didn’t know if that was good or bad, so I pumped it back up both times, thinking consistency was probably best.

Step 15: ‘DeCanning’ the Mold

Ninety minutes later, I take the mold frame out of the vulcanizer (again with the heat resistant gloves on! As expected, it is reluctant to just come gleefully apart, and I must use screwdrivers, a hammer, and a good bit of force to pry off the lids and get my mold out. It comes out alright though, and with less fighting than I could have imagined, and my first thought is that it looks like it might have worked!

Step 16: Demolding the Masters

I take my new mold back up to the studio, and carefully pry out my masters. They pretty much come out okay. The mephit breaks a little bit, and some of the rubber had melted around one of his ‘wings’. I cut a slit into it with the knife, and he comes out fine. My scorpion, Spliffy, also had some minor damage. He delaminated from the penny he was sculpted onto, and one of his little legs broke. Some of the filigree pattern in the pendant also stayed in the mold, and had to be scraped out. All the metal pieces were, unsurprisingly, just fine.

Step 17: Cutting Gates and Vents

Using the surgical blades again, I cut in some gates from the core to take metal to the figures, and some vents to take displaced air from the figures and out of the mold. I’ve seen how Jeff makes his, so I’m pretty sure how I want them to go, but I haven’t had quite as much practice, so mine aren’t nearly as pretty as his. Should work okay, though, I think. There is also a bunch of ‘flash’ and junk around the outer edges of the mold, and around the top hole, and I trim that stuff away too. Now it looks all nice and shiny!

Step 18: Let’s try it!

Back down to the garage! I talc the mold (using regular talc this time, but in the same type of bag as I described for my Mica bag) and put it in the spincaster. I am spinning at around 500 rpms (the only speed my used spincaster reliably operates at…I never mess with the speed setting anymore), and put the mold under about 23 lbs of pressure.

Here’s the result of the first pour. Several of the pieces that I thought would be easy didn’t come out at all, and all the ones I thought would be difficult came out flawless. I probably didn’t just cut the gates big enough, though, and maybe one or two more vents wouldn’t hurt either. I take out the knife and make a few little adjustments, and then try it again.

Step Nineteen: Success!

Woo-hoo! I’ve done it. The second spin and every piece comes out perfectly! Oh, I think I am going to LIKE this!!!

Step 20: Feedback

Okay, now that I’ve done it, here’s where I need your help! All you experienced moldmakers out there, please email me your thoughts, opinions and advice! Anyone else out there trying to get started, thinking about it, or just curious about the process, please send your questions!

What I learned to do here was not easy knowledge to come by…would have been darn near impossible without Jeff! (Thanks Jeff!) Let’s all try to make it easier for the next guy (and help finish my education!!!)!!!

How did I make my own molds? I used RTV rubber, which is short for Room Temperature Vulcanizing rubber. I could build a mold box just big enough to cast what I needed, so it was very economical, and the rubber I used, a putty substance called Castaldo Quick-Sil wasn’t that expensive to start with.

Now, however, I use spin-casting to get much greater detail from my castings. This method of casting uses a large rubber disc shaped mold, which is spun in the machine at high rpms. When the metal is poured in, centrifugal force causes the metal to fly outwards into the mold cavities. This provides much more pressure than gravity casting, and consequently provides much more detail. As far as I know, all professional metal minis you can buy in the stores are cast using this method. It is far superior than gravity casting in every way.

Except…the big round rubber molds are expensive, and they require very expensive equipment to make –which I don’t have. I have to send out to get my molds made. This is fine if I need 15,000 units, but what if I only need a few? Or what if I want to cast up my own masters to make my mold-maker’s (Hi Jeff!) job easier.

Well, I have come up with a way to use the RTV compound to make spincast molds, using old rubber molds as a frame. I’ve heard that other people out there have had some success doing this, but I thought I would share my method in the hopes of opening doors for someone else out there that want to try it, or perhaps learn something from someone out there who already does it better.

Anyway, they say a picture is worth a thousand words, so I have prepared a visual tutorial to hopefully save on some words.

This is an old rubber mold I have been using for this experiment. The mold used to be used to make my gaming tokens, but then I resculpted them, and so the mold was retired and I didn’t feel bad about cutting it up. The little blue rectangles are my first efforts, and they work!

Here’s what it looks like on the inside. You may be ale to see on the left-hand disc where I have marked out a small rectangle where I will be placing my next mold on the disc.

I’m using an x-acto knife to cut out the circle. It ain’t easy. First I make several passes along each line of my box, cutting deeper each time. When I’ve gotten deep enough, I force the knife all the way through and then work it back and forth down the line until I’ve made my cut.

I have successfully cut one side out. Note that on the right hand side, I cut in a little triangle at the top to help act as kind of a ‘Mold Key’. Owing to the fact that all these holes are hand cut, they are all extremely individual anyways, but I figure this will help me recognize which molds go in which holes later on after I’ve been swapping them out for a while (That’s right–you can pop these molds out, put ‘em back, and they still work great!)

Finished with the hard part! After cutting the first hole, I put the mold halves back together, and then trace the shape of the hole over onto the other side. Then I cut it out using the same tedious knife work.

The sulpher in the rubber mold apparently acts as an inhibitor to the RTV…it just won’t cure if it is touching the original mold rubber. My solution: paint the inside of my new mold frame with gesso. Gesso is an acrylic sealant used by artists to seal canvases or board prior to painting on them. It creates an impermeable layer, so the paint sits on top of the board instead of soaking in. It also works pretty good here. I put on two coats to be sure. Normally, I would have used regular white gesso, and you would have been able to see it better, but my white was so old and crappy that it was pretty much unusable. The brown stuff was still good, so, as I’m cheap, that’s what I’m using.

Here I have placed the bottom half of the mold onto a big  plywood  circle I got at the Home Depot. I then fill the mold cavity with plasticine modeling clay.

I’ve just finished sculpting a 15mm skeleton footsoldier, so that is what I am going to be making a mold of. I set him into the clay, and carefully build it up all around him, using the clay to control where my parting line is going to be. Note that I’ve also formed the spue from clay as well.

On the other side of the mold, I fill up the sprue entrance with clay, so the rtv doesn’t go down in there when I fill up the mold and put it under pressure.

Now it is time to make the first half of the mold. I fit the two rubber halves together, and then break out the mold goo. I scoop out roughly equal portions of it, of an amount that looks like it will fill the space I have. A little bit more, actually, because it is better to have too much mixed up than too little. Note that it still is not a lot at all. Imagine if I had to make that whole ring from rtv!

I mix the two colors together, and now I’m on a time clock. This stuff cures completely in about fifteen minutes, so I really only have about 2 minutes from the time I mix it until I have to have it all packed into my mold and clamp it down. I mix the two colors until they make a more or less uniform light green color. It doesn’t have to be perfectly mixed for it to still work properly.

Since the cured rtv would have a tendancy to stick to the porous pressboard, I throw a piece of acetate on top of it.

I then put my other pressboard circle on top of the mold, and use C-clamps to apply a good amount of pressure. The This is why I overfilled the cavity a little bit…the pressure makes sure the rtv gets into every little detail of the figure.

15 minutes later, I carefully pry the two halves apart. If I’ve made my mold right, my original should be stuck in the rtv half now, not the clay. Success! If it had stayed stuck in the clay, I would have just had to dig it out and transfer it to the rtv half, but I hate to do that, because you never know if you don’t get it back in there quite perfect, it may cause some distortion in the cast.

I should point out at this time that the back side of the mold is now pretty much perfectly flat. The rtv under pressure ends up flush with the vulcanized rubber mold frame. The reason is that the outer rim of the frame around the hole I cut will bow out a little bit under the pressure, making enough room for all the rtv. I have learned that this can cause problems later on, as the the vulcanized rubber pushes back on the rtv, and can cause some distortion. We’ll fix that problem in our final step.

First, however, we need to make the other half of the mold. I carefully apply a thin coating of mold release over the rtv. Not the miniature, though. This stuff pretty much just sticks to itself, so that’s the only place I need to apply release.

I have also removed the clay from the other side of the mold frame, and cleaned out any stray clay bits from the frame and from off of my skeleton mini. Also, note that I have filled in the indent I made for the sprue with clay as well, so that after I cast this next side, there will be a hole for the metal to go down, and I won’t have to cut one.

I fit the two halves of the frame together, and simply repeat steps 10-15 to create the second side of the mold.

Here we have the two finished halves of the mold!

As I mentioned earlier, we have to correct the problem of the outer section of vulcanized rubber mold frame putting too much pressure on the rtv. To solve the problem, I simply pop the rtv mold out of the  frame, and trim off about 1/8″ – 1/4″ off the back side. I pop it back into the mold, and it still fits great, but now I won’t get any distortion. I also cut some air vents at key places, and then it is off to go try it out!

From the one, comes many! It takes me a little work to get his sword to start coming out good, but I finally get it, and now my itty-bitty skeleton army is well on it’s way!!!