Working with foam

[AllenB]

Hello all,

First real layout here. I've got insulation foam down on the benchwork as one layer (1 1/2 inch). Then I'll build up/down from there. Couple of questions working with this stuff:

1. It's easy enough to carve with a good blade, but how do you smooth it out? I'm trying sandpaper and that seems to do the trick (320 grit) unless I'm missing something. The dust is horrible.

2. What glue are you guys using to adhear it to the other foam? 

3. Will Plaster of Paris stick to the foam without peeling off?

4. I've got a small creek running through and will eventually try some kind of resin for the water. Will the resin eat through foam and/or plaster of paris?

5. Can you paint this stuff and if so with what?

That's it for now. Thanks!

Allen

[indiana rr]

 I am also building my first layout, and I am also using rigid foam for insulation.  I will do my best to answer your questions with the knowledge I have gained.

1. I use sandpaper to smooth my foam.  I leave a small vaccuum on immediately next to where I  am sanding to suck up the dust.  This is quite loud, so it may not be practical for you.

 2. Liquid Nails for Projects.

3.Sorry, I don't know the answer to this, but I believe Sculptamold does.

 4.I also am not sure on the answer to this, but I am under the impression that resin specifically for projects will not (i.e. Woodland Scenics' Realistic Water)

5.  I use regular acrylic paint.

Happy Modeling.

[ratled]

1. It's easy enough to carve with a good blade, but how do you smooth it out? I'm trying sandpaper and that seems to do the trick (320 grit) unless I'm missing something. The dust is horrible.

 A shop vac is a must.  I did use sanding blocks down to about 200 - especailly at transistion points at hills for the track.

2. What glue are you guys using to adhear it to the other foam? 

Alot of guys are using caulk but I found it too expensive,  I use yellow construction glue.  A gallon from HD/Lowes is about $10 and will last you the whole layout

3. Will Plaster of Paris stick to the foam without peeling off?

I don't know as I never ttried it, BUT I do use the plaster cloth foam seams and haven't had any issues.

4. I've got a small creek running through and will eventually try some kind of resin for the water. Will the resin eat through foam and/or plaster of paris?

You'll need to seal it withe something or it will pour through.  Plaster should work.

5. Can you paint this stuff and if so with what?

I use regular old flat house paint.  Walmart sells paint for about $8 a gallon.  I use it mixed 1:1 with water as I would any scenery.  I do have to paint it twice to tone down the color of the foam bleeding through but feel the thined paint flows better over the foam.

 You can see my old bolg spot below and it has a link to some of pictures using foam.  Also, you should consider some of the quality how to DVD's that are out there - Paul Scoles, Joe Fugate, Dave Frary or even the old Green Frog Apple Valley that you can get for $17 on that auction site for all 3 DVDs

ratled

[rrebell]

Get rough cuts with a blade or whatever, If you cover everything with plaster cloth, getting exact dose not matter. Use cheap caulk to glue it together and you don't need that much, a couple of beads will do. Plaster cloth is cheap at $1.00 a roll and sticks great to the beaded stuff and it works on the other stuff I have been told (but can't confirm). The resin will not eat the plaster but will eat the foam.  I paint the plaster stuff all the time and you can paint the foam  if that's the way you want to go.

[ARTHILL]

For a top coat I use my version of ground goop (Lou Sassi). Premixed Dry Wall seam cement, latex paint for color, saw dust for texture, Lysol for mold control ( acouple drops will do) Water for thickness. If I just want color and texture I make is thin. If there are a lots of holes to fill, l do not add water.  I "paint" it on with a cheap paint brush.

 I like to glue the pieces together with a low temp hot glue gun. The high temp will melt the foam. That is MUCH faster. I can stack a dozen pieces and carve them immediatly.

For fany carving, I paint the foam direct with tube acrylics.

The key to making rocks and mountains and canyons it to be rough. I like a serrated steak knife for carving. A stiff wire bruch is also useful.

You can see some of what I have done in the pics in my sig. 

 

[HHPATH56]

Why don't you apply scraps of Styrofoam for small undulations of the terrain. I would suggest that you get a couple of rolls of Plaster Cloth, wet it, and apply it to your rough cut plaster. You do not have to smooth the terrain with sand paper, (unless it is to be a smooth road or river bottom, where I use the smooth variety of Hydrocal Plaster.). I then apply either Sculpmold plaster (which (on hillsides), can be carved, or various forms of Hydrocal Plaster, (for areas of rough hands-on usage. Hydrocal Plaster may require the use of a primer. If you plan on extensive use of Hydrocal plaster, it can be purchased in large quantities at many lumber yards. For coloring the terrain, I use aq variety of spray can colors. If one gets flat Latex paint, one can mix it in the plaster. This is especially useful when one plans to drill holes for "planting trees". (Or just respray, after vacuuming off the plaster dust.) For rivers, you paint the Hydrocal base (which is water proof), apply blueish green, shading to brown toward the shallow water. I then use either Envirotex or Magic Water (which is a two part resin) It has a tendency to creep up rocks or log debris, placed in the river bottom. But you can paint over the "creep". I often use Woodland Scenic "Water Effects" to show "white water" of rapids, and water falls. If you plan to Post a digital photo of your layout or diagrams, you must first put the photo in a Host (such as Photobucket.com). Place the photos in a model railroad dedicated album of "My Albums". Below each photo will be four options. Click on the bottom "IMG" option, Momentarily, it will say "Copied". Go to the place on the Thread of the Trains.com Forum, (where you must be Registered, if you plan to start a new Thread, or Reply to someone elses Thread). For a Reply, you first type in the Text that you desire, and then click on ctrlV The lengthy code will appear for your photo. Scroll down to Post and click on it. Soon, your Post will appear at the end of the rest of the Thread. You can always click on Edit,( above your Posted text and photo), to correct typos, or delete any or all of it. Bob Hahn Click on the photo to enlarge it. Then click on the photo series at the left, to see other parts of my HO layout.

[twhite]

I can answer a few of your questions, as my entire garage layout is built with 2" Corning foam.  First of all, the foam will glue together quite well with regular yellow construction glue (I use Elmer's).  And yes, it will take plaster without any problems.   I know it will take ordinary latex house-paint quite well, though I've never really painted any.  All of my 'raw' foam has been hidden with plaster-based scenery. 

As to using 'water' on foam, make sure you seal it first with a good, solid coat of plaster to seal any leaks.  I used several layers of carefully smoothed out plaster cloth for my large water-course on my layout, and it worked very well. 

I don't used stacked carved plaster for scenery, instead I use the standard support/newspaper/plaster cloth 'zip' method and cast my rock-faces with Sculptamold, so I can't help you as far as carving.  But either a hot knife or a serrated steak knife seems to work extremely well for the foam mountains I've seen on other layouts (Art Hill's is a really fine example, IMO).

The major plus I've found with foam is that it's lightweight but fairly strong (and stronger as you stack it), and can be supported by somewhat lighter benchwork.   I've heard from several modelers that it tends to be 'noisy,' but I've never found that.  I use foam roadbed, and most of the time, all I can hear from my trains is the 'clack' when the wheels go over a rail-joint. 

I like it.  It goes up fast and is easy to work with.

Tom  

[rrinker]

 I use yellow glue to attach the foam to the wood structure, caulk for everything else. Caulk, expensive? Stop using the designer brands with silicon. I laid all the roadbed AND track on my previous 8x12 layout with ONE tube of $1.19 basic latex caulk.

                           --Randy

[CascadeBob]

 Can you give some sources where you can get plaster cloth at $1.00?roll?

Bob

[rrebell]

Sure ASW warehouse, buy their off brand in bulk, they are always offereing 20%off. If you can't wait for a sale Dick Blick offers theirs day in day out for $1.49. Needed a bunch and a forum member turned me on to ASW.

[Allegheny2-6-6-6]

 #1. For sanding I use 40. 80. &100 grit makes it as smooth or as rough as ground texture needs to be.

 

#2. For glue I use Liquid Nails for projects and on occasion Hot Glue for doing scenery 

 

#3. When plastering over extruded foam I like to rough up the surface first or put a layer of plaster clothover the foam first.

 

#4. Fro water I use only Envirotex Lite. It's a little on the costly side but it produces great water effects with no yellowing. I seal all joints where glued with latex caulk just for good measure but it maybe that the plaster is enough to seal it but why take the chance. Caulking is cheap insurance.

 

#5. Yes it can be easily painted with any Latex paint. I hate that god forsaken pink so I usually wind up painting everything a desert tan first before ground cover etc.

Also Plaster cloth can be had very cheap at A.C.Moore especially with one of their 40% or 50% off coupons. When they run the 20% your entire purchase thats when I stock up on supplies.

[BATMAN]

 The only thing I can ad to this is, line your shop vac with a plastic bag when vacuuming up the foam. When your done pull it out and save the foam for small rocks and ground cover. It stays quite clean when you do this instead of pulling out of a dirty drum.

 

                                                                              Brent