Archive for March, 2007
Looks like 2007 is going to be a very busy year for Adepticon. The 40K Team Tournement sold out a week ago & the 40K Championship closed out Tuesday. Pre-registrations have already exceeded last years total attendance! See you all tomorrow.
A few advanced pics of the Adepticon gaming halls.
War Hammer Fantasy & Specialist Games Pavilion
A hint of the new Lord of the Rings terrain pieces.
The mold for my 25mm bases came out better than expected. When glueing in the masters, I took extra time to make sure to make sure the seal was even and without any glue build up. I was rewarded with cleanly cut cavities for each base.
After removing the Lego mold box, I got out my handy sculpting tool. Some times the mold is difficult to release from the master & a bit of soft scraping is needed to get under the mold. But in this case, all that was needed was a bit of finger pressure to release the mold.
The 10 master bases survived the molding process & are still firmly attached to the MDF base board. If need be, I could remove the bases & use them on figures. Instead, I’ll store the bases right on the board in-case I need to create a new mold.
Not the best of pics, but you can see a bit of a lip running along the edge of the mold. Every new mold needs a bit of clean up where the RTV rides up the side of the mold box. The build up will cause the mold to sit at a funny angle when casting, take a razor and remove the extra RTV.
A bit of an oddity on the cast bases. If you look closely at the masters, these two bases have a total of four rivet holes drilled into them. But the cast bases have all manor of results at the drill holes. The beam on the left has an outie rivet. The decking to the right has everything from a small cavity to a counter sunk rivet to a full fledged outie. All of these are caused by air bubbles getting trapped in the drill holes when the RTV was cast. One of these days, I’ll remember to pick out holes such as these with a tooth pick while pouring the RTV. Until then, I’ll continue to be interested in the what effects an unintended gas bubble can have.
Time to create the mold for my set of 10 25mm bases. The type of mold I work with is generally refered to as one part, open face or dump mold. The mold is a single RTV piece, with open cavities for casting. Makes for easy mold building, but does require a bit more attention when pouring the resin and may require a bit of sanding on the completed cast.
The RTV used for hobby mold making is a two part kit, mixed by weight or volume, and cured at room temperature in 24 hours. My rubber of choice is Mold Max 20 from Smooth On, a 10-1 mix by weight with good strength and a lot of stretchability. For a while I was using a one to one Micro Mark product, easy to use but lacking the durability of the Mold Max.
Step 1: Glue the bases to a firm base, like quarter inch MDF or a thick sheet of plastic card. Surround the masters with a barrier. In this case, I used Legos; handy, reusable and quick to assemble. Other options include build a box out of foam core board, recycled plastic containers or any other frame that can be made water tight. Tacky glue (a thick white glue) was used to attach all elements. The gap filling glue is handy for a project like this and its easy to tear apart at the end of the project.
Once the glue was dry, a coat of Future Floor polish was painted over everything. The wax will seal any porous surfaces and assist in removing the RTV from the masters, mold box and base board.
Step 2: A postage scale, a few cups & a mixing stick is all that’s needed. The RTV comes in two parts. The ’10’ is a thick white goop, the ‘1’ is a red fluid. Don’t let the goop scare you, despite the thickness of the mixture the RTV does a fine job of penetrating small spaces. For this project I mixed 190 grams of white with 19 grams of red.
How much to mix up? – good question. I’m prone to just guessing & then mixing up additional batches as needed. The RTV takes hours to set up, leaving plenty of time add more to the mix. If you want a better answer, try filling the master mold with sand, then pour out the sand into your measuring cup to determine the volume of RTV needed to fill the space. When choosing the thickness of the mold I like about an eight of an inch of rubber, less if only small points of the cavity reach any depth, a bit more if the cavity has a large open space of uniform depth.
Mix the two parts of the RTV well. Try not to fold in bubbles as you stir the rubber. Pour the RTV in a thin stream into the mold box. The thinner the stream, the more bubbles you’ll break as the RTV is poured.
Tomorrow night, I’ll be able to take down the mold box & try a first cast. Always a bit exciting to see if the mold comes out right.
Completed set of 10 bases, suitable for use with 40K or other miniature games. Now that I have 10 bases prepared, next set will be to set up a mold box & create an RTV mold of the masters.
Material list is basic:
- floor tile
- plastic card and rod
- plastic card with tile design
- variable grain sand
- super glue
Tools are similarly basic:
- exacto blade
- side clipers
- scribing tool
The scribing tool is the only item that may be hard to find. I purchased mine at a local ACE Hardware for $6.00. The tool is used to carve the tile etchings into the floor tile. One method to remember, if your going to smash the tile into bits – carve the lines in first & then be sure to line up the pieces so all the line run in the same direction.
If you are building bases for casting purposes, watch out for over lapping bits. Laying bits at an angle is a nice effect, but you must seal up the triangular hold between the pieces. On the left the top piece (where its casting a shadow) forms a significant under cut. If I don’t get back in there with some more super glue & sand (or some sort of epoxy putty), the mold will get “under” the bit and create a space in the mold that will tear at the rubber with each cast. The base on the right has an open gap between the tile and the over laying piece of plastic card. When the RTV gets under and forms a strip of rubber – you’ll have a devil of a time getting this base out of the mold.
I had a splendid time at the Games Plus spring miniatures auction. Appeared that 40 to 50 people came out as buyers, and the sellers must have had 500+ items up for bid. The auction was run smoothly, with 2-3 items per minute hitting the sales floor.
The miniatures for sale came from a broad range of companies: roughly one third GW, with strong showings from Confrontation, SST, and Warmachine. Bidding ran about 40-60 percent of retail with most items getting at least one bid (and frequently multiple bids). I found out later that a few Ebay sellers were in the audience keeping up the minimum bids.
I was please to see that all my times sold.
Set of 6 40mm bases: averaged $4
Bag of obstacles: averaged $15
Ruin building kit: averaged $15
Bag of 14 crates: $10
Terrain of all types sold well. Large foam ruin buildings sold in the $15 range. Painted Rail Road buildings from $15 to $22. Three sets of 10 razor wire sold for $12 each. And a number of Hirst builds sold: Bridge $20, Octagonal tower $32, Tomb $40, Bell Tower $50 and Cathedral $66. For the Fall auction, I need to bring in some painted Hirst kits of my own.
New project: 25 mm urban style bases for 40K.
WIP photo of the first 6 bases. The remaining exposed surface of the base will get a coat of sand. These are the first in a set of 10. With any luck, I should have cast examples ready for the Adepticon bitz swap.
I provided a bit of advice to friend for a resin casting project. He wanted a resin to cast medallions in a one sided mold using a colorant. Smooth On (my supplier of choice), listed an easy to color resin: number 320. Somewhere between my recommendation and the purchase, 320 became 325. And an off-white resin became a clear casting resin.
For our hobby of casting gaming pieces – 325 is the absolutely wrong resin. It’s clear and refuses to take paint. If you use a colorant – the result is a semi-clear, lolly pop like finish. Maybe there is some fun application for this resin, but it’s not in the painted miniatures hobby.