Monday, April 22, 2013

Finishing and Casting the Peter Laing Molds

Molds after first half dried.

Preparing to pour the second half. Putting on mold release (I use plain petroleum jelly). You only have to put it on the rubber itself; the rubber will only stick to untreated rubber.

I used to pull the mold out of the frame. Now I just carefully push the mold down flat on the bottom. If there is any gaps between the mold and frame, put a bead of petroleum jelly between the mold and frame so the rubber won't seep down the sides of the mold.

Mix the rubber as before and work the rubber around the figures as before.

The molds after they have dried and been separated.

Make sure that the pouring spout is clear so the metal can get into the mold. Also make sure the air vents  are open at the top of the mold.

The molds have been prepared with talcum powder that serves as a release ( you can also use graphite). Boards are used to hold the molds together without crushing the rubber, and then clamped together. I do this as the metal melts.

Carefully pour the metal in a steady pour. Fill the mold right to the top of the pouring spout. Also, make sure the molds are dry. If there is dampness, the molten metal can be ejected out the way it came. Wear safety gloves and glasses.

After pouring the metal, tap the mold on the workbench to help get the metal  down into deepest parts of the mold (roughly about 5 seconds).

Molds after pouring. The first couple of figures might not come out. The molds have to warm up . Now's the time to look for imperfections and see how to get the molds to fill properly.

Here is a shot of the masters and home casts. As can be seen, the hussars sword didn't come out, and the flag looks like it's been through some heavy fighting. I cut a new air vent from the sword to an existing air vent, which seemed to help. The flag is still giving me problem.


2 comments:

  1. John - I think those casts are looking really good. In terms of missing swords and flags, I would personally replace those on my figures anyway
    Ian

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  2. I really think the built in air vents was a big help. I just finished the Crimean War Highlander standard bearer. The flag came out better on this figure.

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