Molds and Rock Faces

[dturnerfish]

I hope in my layout to have numberous rock faces and cliffs. I am not sure how this is accomplished. You can purchase molds, but I would think they could only be used a few times (one whole, and thers in pieces). It would look odd to have the exact rock faces throught your layout.

How do you all deal with this?



Thank you,
DT

 

[tillsbury]

With rotation and surreptitious chopping, it's surprising how varied you can make a limited number of moulds look. I managed about 18" of cliffs out of one WS mould, and you can't see the repeats (unless you know where to look). I would have thought three would give you a lot of rocks...

 

[hminky]

I have had good success using ceiling tile for rocks and have a web article at:

http://www.pacificcoastairlinerr.com/more_rocks/

I have also experimented with cork sheet for thin layer sedimentary rocks but haven't had a chance to do it on the layout:

I have web article discussing thin strata rocks at:

http://www.pacificcoastairlinerr.com/thin_rocks/

Thank you if you visit
Harold

 

[ddavidv]

The cheapskate method of making molds (at least in N): use aluminum foil as a mold! It takes a little practice, but with a half-dozen attempts I was able to pop out some pretty decent rock faces. You do have to be cautious of tearing the foil. I just mix up some lightweight hydrocal and pour it in. One of the challenges was keeping the overall 'depth' of the casting down. I find it's better to make the castings first, and then build the scenery they will attach to. If the casting breaks when you remove it, no biggie just to spray some water on it and dab a little powdered hydrocal in to fill the gaps.
Here's a not-particularly-good photo of some smaller rocks I did on my module:

 

[MasonJar]

Moulds are great for igneous or metamorphic rock, but as Harold mentioned there are a number of ways to make sedimentary rocks. I made mine with the "slash" technique. More about that in an article I wrote for one of my local clubs newsletter - Small diorama kick-starts layout landscaping

Andrew

 

[inkaneer]

My method is more time consuming but I think the results are better. I pour a plaster mix ito some crinkled up aluminum foil. Iusually tint the plaster first with whatever rock cover I want.. I allow it to se up for at least 24 hours then I take out of the aluminum foil and place it in a zip lock plastic bag. I place that on the floor and step on it. From that I get individual rocks that I then "glue" in place with some soupy plaster or latex caulk. Makes great sedimentary rock and shale. There is a lot of waste with this method so I don't recommend it for extensive areas but for a foreground scene it can't be beat. Another way is to make several such faces and then make a mold of them. That way you can cast copies and then break those up into smaller pieces and use those to build a rock face. Everyone will be different.