| GROSSMAN | 29 May 2013 10:12 a.m. PST |
I have some 2-D casualty figures I wanted to cast and I was planning on using air dry clay as a mold and pouring in resin to make the figure, will this work? Any experience with this or something along the lines would be a great help. Thanks Mark |
| RavenscraftCybernetics | 29 May 2013 10:35 a.m. PST |
if the air dry clay isnt flexible when dry, it wont work. |
| 45thdiv | 29 May 2013 10:39 a.m. PST |
If you want to go clay route then us the plastic/wax based clay. You are only going to get one mold at a time, but with this clay you can reuse it. The air dry you will get one use and destruction it with every casting. |
| Ron W DuBray | 29 May 2013 10:42 a.m. PST |
your better off getting some 2 part sil rubber for the mold. Its cheep and easy to use. |
| Pictors Studio | 29 May 2013 10:48 a.m. PST |
What did you sculpt the casualty figures with? That might help us in telling you what would be the best route to go. |
| The Tin Dictator | 29 May 2013 10:58 a.m. PST |
A problem with using clay as the mold is that after you press the figure into the clay, you have to remove it and that will distort the clay. So unless you like oddly distorted figures, it won't work. Air drying clay will dry stiff and removing the master figure will probably just break the mold. Use RTV.
Grab the Alumilite pack they sell at Hobby Lobby. Its relatively cheap. |
| Simcoe 2000 | 29 May 2013 11:28 a.m. PST |
Use RTV! Be wary of anything else! If the clay has sulfur in it, you will get an unwanted reaction. The resin will react with the sulfur in the surface of the clay and will not cure! It's a mess! Check out some of the one shot mold making kits that Alumnite sells. |
| GROSSMAN | 29 May 2013 11:43 a.m. PST |
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| James Wright | 29 May 2013 12:24 p.m. PST |
If you are feeling cheap, you can use silicone calking as well, you just need to put it on in thin layers. I use it for simple molds of flat castings like casualty markers etc. That said rtv rubber is the best way to go. |
| redmist1122 | 29 May 2013 12:44 p.m. PST |
If you go the HobbyLobby route, and have a smart phone or equivelent, then get their app, and save 40% off one item daily. P. |
| GROSSMAN | 29 May 2013 1:18 p.m. PST |
Thanks redmist-good idea, but it looks like there isn't a hobby lobby within 75 miles of me. |
| Zephyr1 | 29 May 2013 2:38 p.m. PST |
Second the 100% silicon caulk. It's not the greatest (as it can warp), but works for simple stuff if you're desperate…. ;-) |
| GriffinTamer | 29 May 2013 3:02 p.m. PST |
Smooth-On makes an intro kit that includes silicone mold material, polymer resin, release agents, etc. for about $50. USD Enough silicon for a handful of molds, and enough resin for a whole lot of 28mm scale figures. Should be pretty simple to mold up flatter figures (like prone casualties). Here's a link: link For more complex (upright) 2-part molds there's more work involved, and you'd need a non-sulphur clay as well. |
| pahoota | 29 May 2013 3:44 p.m. PST |
If you're only casting objects with a flat bottom, modeling clay works fine as an impression mold. I'm not talking air drying clay, but modeling clay that generally holds its shape but never "dries" or sets. I use Van Aiken brand Plastalina and it's perfect with resin. Model clay impression molding is how I made the tanks here at this link:
TMP link I've done plenty of silicone mold-making and resin (and hot lead) casting and believe me, for 2D simple objects clay is easier. Here's a photo of a mold made with modeling clay, right after the cast was removed.
More discussion on impression molding at my blog if you're interested: link |
finds a personal connection to WWII.
