GRP hills

Has anyone here tried GRP as a medium for building hills? I was thinking that GRP moulded onto an exmet armature would be light and easily removed for sections of hill concealing trackwork.

Guy

Reply to
Just zis Guy, you know?
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IF GRP is what I think it is, we call it fiberglass. ;-)

I haven't heard of anyone using it for a scenery base. IMO, it would not be any lighter than most other materials, would be more complicated to build (not to mention requiting chemical hazard protection), and would cost a fair bit more. OTOH, for a larger removable scenery section, as you envision, it might be worth the hassle, because its strength would reduce or eliminate warping as it was lifted out of the way.

However, I think that for most purposes the best material for light weight and strength is extruded foam plastic insulation board - _not_ the beaded stuff used for packaging. I'm puttering away at a 31"x48" N scale layout built on 4" thick insulation base, made by cutting an 8' board in half and gluing the pieces together edgewise. I glued two pieces of 1/8" ply crosswise underneath to tie the two chunks of insulation board together, but they're not needed. Scenery is stacked and carved 1" thick board with a plaster-gauze skin. The layout is light enough for one person to carry, although the size makes it a bit awkward. ;-) No twisting whatever when lifted.

If you experiment with GRP, do report back here.

cheers, wolf k.

Reply to
Wolf K

Knew someone who used it some years ago - Fine but stank the house out - they suggested doing it in the garage in future. Might be an alternatve to plaster and gauze but the heat as the glass sets would be troublesome for expanded foam so chicken wire on timber supports would be the way to go methinks. Personally I have found torn up newspaper and runny glues (various depending on what needed using up) works okay, once done its easy to poke holes to insert trees, with fibreglass that might be more difficult. The paper on a big job like that takes a week or so to dry in normal Manchester (UK) weather.

Regards

Mike

Reply to
Mike Smith

GRP is overkill. An American company has been using the fine mesh used to keep insects out, and pouring the liquid plastic mixture on that, since at least the early 1990s. He calls it geodesic foam.

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Reply to
Christopher A. Lee

Neat-o, as our Leftpondian friends have it.

Guy

Reply to
Just zis Guy, you know?

Where are you buying it, Wolf?

Guy

Reply to
Just zis Guy, you know?

I've seen his demos at shows. He also uses foam baseboards, and laminates foam spars with thin plywood for the framework.

Major shows on the East Coast fly him in from California.

The first time I saw him he was using bubble wrap instead of fine mesh.

He also does resin casting demos and materials. Very useful for things like O-scale grease axleboxes instead of waiting for white metal castings from the UK.

Reply to
Christopher A. Lee

This is Canada, so the stores are Home Hardware and Building Supplies. Also available at Rona, Home Depot, etc and so on and so forth. I don't know who sells the stuff on the UK.

If you have a friend in the building trades, you can often get waste (offcuts) for free. I got the 3-1/2" and 4" thick stuff from a bricklayer friend. He'd picked up waste pieces for his layout, and passed a few on to me.

cheers, wolf k.

Reply to
Wolf K

In the UK, the best known trade names are Cellotex and Kingspan. Wickes sell the foil faced Cellotex in various sizes and thicknesses. Alternatively you can get "seconds" from

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I haven't checked of there's a minimum order, or what the delivery will be.

A good source for offcuts is a skip anywhere where someone is having a house extension or loft conversion. UK Building regs mean that this stuff is virtually mandatory to meet thermal insulation requirements. You must ask before taking anything from a skip, though.

MBQ

Reply to
Man at B&Q

PU foam was a great idea, Wolf! I have bought a couple of 8 x 4 sheets, 100mm and 25mm thick, total price about £40. I wish I'd discovered this ages ago, it has good noise-damping properties plus you can carve it - no more flat landscapes with the occasional appliqué hill, streams can be carved in and all sorts! What a world of possibilities this opens up.

Guy

Reply to
Just zis Guy, you know?

You're welcome, Guy, but I can't claim credit for it. I'm not sure who was the first to use it, but Model Railroader used it on its Turtle Creek project layout a few years ago, and since then it's become one of the three or four main scenic base materials over here.

I use a serrated bread knife for cutting out pieces roughly to shape, and a 3" or 4" paring knife for slicing off bits to make slopes, etc. If you push the knife in near the edge and twist, and a chunk of foam ill come off - the irregularities are good start on rocky outcrops, cutting faces, etc.

FWIW, I won't be going back to cardboard strips or wire mesh etc. ;-)

cheers, wolf k.

Reply to
Wolf K

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