First attempt at a rock mold

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wheeler1963

wheeler1963

Wheeler's Trains
I tried my hand at making a rock mold so I can increase the size of the diorama I got from Anton. I don't think it came out too bad.

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Rocks

That rock face came out quite well, Jerome. Did you use aluminum foil? A spray of india ink and alchohol and some light dry-brushing for highlights will help it look even better.

Roy
 
Roy, Thank you. It came out of a Woodland Scenics mold. Can you explain the weathering technique your talking about. I've never done this before.
 


Came out good Jerome. I've got 3 or 4 of the WS molds and find them pretty versatile. When I pour some I make several and put them aside in raw hydrocal until I have a need for them. Depending on the area I am doing the scenery I use them as is or cut them in half either sideway or up and down, install them horizontally or vertically, etc. One area I have completed uses the same full size rock casting 3 times in a small area and unless I point it out the repitition goes unnoticed. Smaller castings are good to add contour to an otherwise flat ground surface. Just place a piece of 100 grit sandpaper on your bench and flatten the back side of the casting and you won't have to add a lot of dirt and weeds to hide an uneven edge where it sits on the ground.
 
Mix up some india ink and alchohol, dark but not to dark. Place the casting in a position similar to what it will be on the layout and spray this over the casting. Let the alchohol run the ink into the creases of the rock. Once this dries take a contrasting colour, lighter tan, off white, black?, etc., and lightly drybrush the higher points of the casting. The colour is up to you. Check out real rocks that you're trying to imitate and play with the colours on different pieces until you get your technique down and a colour combination that you like. The key is to not have a uniform colour over the whole surface of the rock casting.

Good luck and have fun.

Roy
 
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Jerome- you can easily make your own rock molds from broken pieces of coal, shale or sandstone to name a few.
Spray the rock with WD40 or cooking oil, (Or "paint" with petroleum jelly) as a mold release, and coat with liquid latex from a craft store. Let dry overnight and recoat. Repeat 2 or 3 times. Add a layer of cheese cloth, bandage gauze or old teeshirt and another couple coats of latex. You need cloth every 3 or 4 layers. Smaller molds need 6 -8 layers of latex and larger molds need 9 -12 layers.
You can also make rock walls, foundations and junk piles this way.
Make a styrofoam frame to hold your mold until the plaster or hydrocal sets up.
 
I used the Woodland Scenics rock moulds too, for my layout.Once I had everything fixed in place, I used an aerosol can, of primer grey as a base coat. Then a dusting of matt black from another aerosol can, to bring out the details better.Finally I used an acrylic burnt umber water colour wash, to tone down the grey and black. I need more foliage,and small trees planting in cracks inbetween the rocks,but so far I,m pleased with how it looks .
Ron
 
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Ronzzr, I like that wall. The diorama that these will be going on is only about 1 level high, yours looks about 3 high??
 
Thanks for that !!
Yes, mine ended up three castings tall. I made the basic shape from layers of insulation foam,and stuck the castings to that.
Ron
 


OK, this is the first mold that was brownish in color. I don't have any india ink, so I sprayed it with AIM Products Quick Age. Made it a lot darker.

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This is the second mold straight out of the casting.

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And the same one with just a spraying of Quick Age.

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Looks like the Quick Age does the same effect as an India ink wash. Your first mold looks great with the Quick Age on it. Some dry brush streaks of rust and white will add depth and appear as mineral deposits in the rock. Nice thing about plaster is it doesn't cost much so if you overdo it when coloring there isn't much to feel bad about other than the time spent. I've even airbrushed over them with a light tan paint and started all over again.
 
Mike, I'm glad you told me that. I've never seen a mold with just India Ink on it. So I know I'm headed in the right direction. ;) I've made no progress today, had to shut the shop down. Windows are being installed in the house tomorrow so I had to move everything around a bit.
 
Jerome, this is the same rock mold you show. I used it 3 times within the same corner in front of and beside the RS3 #590. In front of the loco the casting was shortened in length. The casting on the bottom beside the loco is full size but placed upside down after flattening the curved top and the one above it is from the same mold but shortened in height and only the curved top portion was used. Coloring is lighter than what you did but to my eye it is typical for the area I have them placed in. Base color is Floquil earth thinned to a stain and applied with a soft brush. Streaks are thinned Floquil rust and Model Master burnt sienna. Final application was a wash of India ink.

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OK, I need some expert help again. I bought another mold, this one has 3 smaller castings. I figured that the smaller castings would come in handy filling in the gaps as I try to put these altogether. Here's today's moldings.

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Now 2 questions:

1. Is there anything I can use to glue a casting back together that I snapped taking out of the mold?

2. What can I use on the molds themselves to clean them?? They are getting a bit clotted with the Hydrocal.
 
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