Disaster Has Struck

Discussion in 'HO Scale Model Trains' started by BudM, Jun 7, 2008.

  1. MasonJar

    MasonJar It's not rocket surgery

    Oct 31, 2002
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    Not sure whose rock moulds you have, but did you follow their directions? Usually some sort of release is required (light coating of vegetable oil, or sometimes a dusting of dry plaster before pouring - check your product).

    The other key to getting the rocks out and onto the layout is to remove them before they are fully set. This way they are bendable and can be formed to the underlying structure, and can also be touched up with a dull blade or other "carving" tool.

    You can also wait until they are solid, and apply them like ceramic tile, by buttering the backs with a generous amount of plaster.

    Hope that helps.

  2. Russ Bellinis

    Russ Bellinis Active Member

    Feb 14, 2003
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    Check out Bragdon Enterprises Bragdon Enterprises - Cutting Edge Model Scenery Technologies His sytem will work with any latex rock mold. He uses Vaseline rubbed into the mold until it disappears but the mold feels a bit greasy, then spray the mold with lacquer paint (outdoors with a mask, you don't want to breath the fumes!). The paint over the Vaseline makes a mold release.He then uses a 2 part foam product similar to "Mountains In Minutes", but it is mixed in a paper cup, not premixed in a spray nozzle. The entire process in on his web site and the results are great. The "rocks" stay slightly flexible, lightweight, and strong.

    I forgot to mention that after the rocks come out of the molds, with the foam, you can cut them up and rearrange them any way you want to increase the combinations of rock you get out of each mold.
  3. BudM

    BudM OldGuy

    Mar 26, 2008
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    Rocks and Rock Moulds

    Many thanks everyone for all the terrific suggestions. I went at it again this morning and found that I wasn't waiting long enough or was waiting too long. I found a neat way to "test" the rock while it's in the mould and that is by pushing a pin into the mix. If I get a little resistance, then the mould is ready to apply to the rock wall. It has to be just a little flexible, not a lot, and it'll work just fine.

    The other secret is to make certain to wet the wall with "wet" water before applying the mould to the wall. Hold it on for about a minute or so and then let it sit for another half hour or so. Then, I carefully peeled off the mould and voila!! I had my first good looking rock face. A little digging here and there around the edges made it look more natural and the next step was to apply another right up next to it.

    Now I'm feeling better but the ink still isn't 100% out of the rug yet either. Oh well, still at it. My wife says, "don't worry dear, you'll get it eventually". No wonder I love this woman.

    Thanks again lads, all the help is most appreciated.

    Bud M.