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How do you carve/cut foam?

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Posted by Old King Coal on Thursday, December 14, 2006 10:13 PM

The initial free-form shapes are cut on a bandsaw or jigsaw, then contours rough shaped with a course abrasive wheel mounted on a cordless drill.

The finer detail is applied by means of a dremel tool with a fine wire wheel attachment.

Final finish details are accomplished using a electric heat stripper to gently "flame" the surfaces of the form. This technique removes all the fuzzy edges on the Styrofoam, and also creates smooth indentations where necessary.

Paint used is water based latex which also acted as a adhesive for ground cover & rock formation applications.

This is what works for me.

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Posted by gwg50 on Thursday, December 14, 2006 8:57 PM

 jerrylovestrains wrote:
I use a custom 14 gauge solid copper wire which I put into my weller soldering gun. Make for quick cutting, and you can bend the wire to make different jagged ( rock) patterns!!

That is how I've been doing it 10,12,14 gauge solid. been working fine. 

GWG

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Posted by RR Redneck on Thursday, December 14, 2006 7:05 PM
Ha!!! I like that.

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Posted by pbjwilson on Thursday, December 14, 2006 7:01 PM
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Posted by dougdagrump on Thursday, December 14, 2006 12:11 PM
After rough cutting with with one of several different saws I use a plain old wire brush to create the final shape that I am looking for.

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Posted by jkerklo on Thursday, December 14, 2006 8:43 AM

I use a home-built hot wire foam cutter for scenery as well as for making carriers for accessories and trains that are going to a show.

 

It started with a 20 ampere step-down transformer  that had been tested but was still on the test stand.  A line Variac feeds the transformer.  An AC  current meter is used to adjust the Variac and set the current through the Nichrome wire.

 

 

There are also setups for cutting up to an 18 inch stack of foam and for slab cutting a sheet to a smaller thickness. 


This is the sort of thing it was first used for:

 

 

The holder for 153's was made before I discovered that pink foam was better than the white.  The white stuff is still flaking off and leaving a mess.

 

 

 

 

 

 

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Posted by NewEYP on Wednesday, December 13, 2006 11:32 PM
I have used a large grinding wheel mounted on an electric drill. It gives a nice irregular finish to the foam, but is very messy. I then paint the foam with a couple of coats of thick paint in an appropriate background color (murky brown, blah grey, or some combination) which hides the foam texture.
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Posted by Ole Timer on Wednesday, December 13, 2006 11:15 PM

 As far as the rough looking angles left after cutting styrofoam . I use a pencil tipped torch to mold the terrain . STAY BACK ... don't get real close ..only to the point where it collapses . It is highly flammable and will catch fire ! I take mine outside . You can get real authentic structures on mountains and hills . But experiment with scrap pieces to get the right touch . A scrap tablespoon dipped in water molds it how you want it .  I always have a container of water handy just in case .  

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Posted by dwiemer on Friday, December 1, 2006 12:36 PM

I use Liquid nails for projects, but read the label as some LN are not meant for foam and will melt it.  Also, if using a hot knife or any other method that "melts" as it shapes/cuts, avoid using it on white foam, and on the others, make sure it is well ventillated.

Dennis

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Posted by Birds on Friday, December 1, 2006 8:41 AM

Thank you for all the replies!

Buckeye, I appreciate the link to the photos. 

I've never done any work carving foam, so this is new territory for me.  I'm looking to build a "lift off" mountain with tunnels in a corner of the layout.  So if some of my questions seem simplistic or basic, bear with me. 

When you cut and shape the foam, do you always have the foam for the landscape all stacked and glued together before carving?  (Say for a tunnel have everything stacked up and looking like a  large square or rectangle with holes in the base?)

Are there certain glues that I should use or avoid when doing this?  (We have a hobby sized hot glue gun). 

Does the carving end up being sort of free form, or do you draw a rough idea out on the foam, or does it depend?

I can see me trying to get my cuts too neat and not ending up with a rough looking mountain, but something rather angular and geometric.

Thank you, 

Chris 

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Posted by Jumijo on Friday, December 1, 2006 5:42 AM

I use a hacksaw blade. It gives a nice rough texture and makes short work of cutting the foam.

 

Jim 

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Posted by FJ and G on Thursday, November 30, 2006 6:20 PM
I've tried all methods from saws to heat methods but my favorite for speed is the sawzall with a nearby monster shop vac turned on nearby to suck up the flying beads.
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Posted by Buckeye Riveter on Thursday, November 30, 2006 4:57 PM

I used pink, blue and white.

You can see more of my construction photos at this Shutterfly website.  One of the photos shows the hot knife cutter in a c-clamp.   It worked!

share.shutterfly.com/action/welcome?sid=8ZYtnLVwx8A

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Posted by Anonymous on Thursday, November 30, 2006 4:45 PM
I use a custom 14 gauge solid copper wire which I put into my weller soldering gun. Make for quick cutting, and you can bend the wire to make different jagged ( rock) patterns!!
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Posted by Birds on Thursday, November 30, 2006 4:20 PM

I'll try a knife, but that cheese grater idea is pretty good.  I'll just have to leave the "micro plane" zester alone...

What type of foam do people use?  I've seen the foam from Woodland Scenics, but wasn't sure if the famous "pink" and "blue" insulation panels from hardware stores would also work (can't see why not).

Chris 

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Posted by RR Redneck on Thursday, November 30, 2006 4:06 PM
I like to use a serrated knife to cut the basic shape out then rake up and down it on the foam and let the teeth create random crevices and fissures.

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Posted by Buckeye Riveter on Thursday, November 30, 2006 2:52 PM
I have used a cheese grater to shape the foam.  I also have a hot knife from Tippi (?)

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Posted by dwiemer on Thursday, November 30, 2006 2:07 PM

I have been using a "Mora" knife for most of the cutting.  It is a VERY SHARP knife that I got from Sportsman Guide.  I also have one of the eversharp knives that you see on TV that will cut  a can and then slice a tomato.  Lastly, I have a rasp that I use to shape the mountain and make it coarse so the plaster will stick.

Dennis

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Posted by DCmontana on Thursday, November 30, 2006 2:03 PM
I use a bread knife, outside, on the deck.  It is messy, but I like the way it shapes up.  All my mountains are made of foam, It is quick and relatively easy!
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How do you carve/cut foam?
Posted by Birds on Thursday, November 30, 2006 12:34 PM

What do folks here use to carve or cut foam as they landscape?

Has anyone fabricated their own hot wire foam cutter?

Thanks,

Chris 

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