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Styrofoam - Any Negatives?

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Posted by UNCLEBUTCH on Monday, January 15, 2018 9:49 PM

rrebell
 
UNCLEBUTCH

 

 
rrebell
The only thing you should not do is leave the final surface exposed forever, 

 

Why not ???????????

I'm beginning to wonder if we are talking about the same thing

 

 

 

Beaded foam  can lose beads is rubbed against and in building, running and maintaining a model railroad this is imposible. Also plaster cloth sticks well to beaded foam and gives it a smoth surface that is easy to stain or zip texture. Also it smoths between layers as no mater how carfull a carver you are, layers are layers and this hides them well and if you want to add form you can add more foam and cover that. One of my favorite finish ideas for backdrops is to cut low depth hills and cover them with plaster cloth built off layout compleatly finished with ground cover too. These can then be caulked to the backdrop for relistic hills that take only a 1" or two of valuble real estate.

 

 

 Ok we are not, Your refering to the beaded stuff, and I agree totaly.

I was talking about the blue/pink

please dis regard,

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Posted by rrebell on Monday, January 15, 2018 9:18 PM

UNCLEBUTCH

 

 
rrebell
The only thing you should not do is leave the final surface exposed forever, 

 

Why not ???????????

I'm beginning to wonder if we are talking about the same thing

 

Beaded foam  can lose beads is rubbed against and in building, running and maintaining a model railroad this is imposible. Also plaster cloth sticks well to beaded foam and gives it a smoth surface that is easy to stain or zip texture. Also it smoths between layers as no mater how carfull a carver you are, layers are layers and this hides them well and if you want to add form you can add more foam and cover that. One of my favorite finish ideas for backdrops is to cut low depth hills and cover them with plaster cloth built off layout compleatly finished with ground cover too. These can then be caulked to the backdrop for relistic hills that take only a 1" or two of valuble real estate.

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Posted by PC101 on Monday, January 15, 2018 8:08 PM

If the foam is not covered or sealed and if you use it for roads, parking lots, anything smooth or flat that you will have vehicles (mini metals, model power and the likes) with rubber tires, these tires (some do and some don't) eat down into the foam, yes down to the axels.

A side note, these (some do and some don't) rubber tires will stick themselves to plastic deck autoracks and leave a mark on the deck.  

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Posted by Pruitt on Monday, January 15, 2018 7:29 PM

One downside is that fumes from the foam are toxic. The fumes given off when you use a hot wire cutter can poison you, so be careful.

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Posted by UNCLEBUTCH on Monday, January 15, 2018 6:04 PM

rrebell
The only thing you should not do is leave the final surface exposed forever, 

Why not ???????????

I'm beginning to wonder if we are talking about the same thing

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Posted by Bubbytrains on Monday, January 15, 2018 3:51 PM

Very interesting, I have never experienced that, and I live where temperatures and humidity cause everything else to warp. I can't imagine why styrofoam sheets would warp because they contain no moisture and have a uniform consistency. Guess I'm just lucky. Homasote, on the other hand......!

Bubbytrains

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Posted by rrebell on Monday, January 15, 2018 10:13 AM

Also I have done in house cutting, you just have to be carefull and not go hog wild. Also we are not talking yjat many beads floating around because most work will be done with got wire, you could do it all with a larger hot wire, you can, make one or with a lot of waste. Like I think I said before, you can also use a hot knife but you need a tempeture controled one to avoid the toxic gasses or get a resperator or just use a long thin blade, more difficult but doable. The only thing you should not do is leave the final surface exposed forever, thats why the plaster cloth but then the plaster cloth is there for other reasons too.

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Posted by UNCLEBUTCH on Monday, January 15, 2018 10:11 AM

rrebell
Trouble with both blue and pink is they warp over time, ussually this dosn't mater but.

Not to argue with you, but I never seen foam warp.

I picked up a sheet of 1in blue that was out doors so long that the edges where rounded over from the wind, and the color was faded to almost white,still flat.

 Glued with caulk, on a frame, it aint going nowhere

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Posted by rrebell on Monday, January 15, 2018 12:49 AM

Trouble with both blue and pink is they warp over time, ussually this dosn't mater but. 

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Posted by mbinsewi on Sunday, January 14, 2018 8:14 PM

Attuvian
General question: between the pink and the blue, is there any significant difference in either the composition or densities? So far in Portland, I've only found the pink.

Nope, not for model railroading uses.  You only need to worry about the density if your going insulate under a concrete slab.

Mike.

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Posted by Attuvian on Sunday, January 14, 2018 8:10 PM

All,

General question: between the pink and the blue, is there any significant difference in either the composition or densities? So far in Portland, I've only found the pink.

John

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Posted by jjdamnit on Sunday, January 14, 2018 7:21 PM

Hello all,

I use the 1-inch extruded "Blue Foam" for the base of my pike.

This pike sits directly on the bed in the spare/train/library room.

I upgraded the base from 5/8-inch MDF underlayment to a framework of 1"x4" with an underlayment of 1/4-inch plywood.

Because there is no under pike access, I carved channels in the foam and lined them with 1/2-inch split nylon wire tubing. Similar to the prototypical use of utility tunnels.

When I carved out these channels; with a 1/2-inch wood chisel, the pieces of "Blue Foam" were large enough I could sweep them up with a large paint brush or by hand.

The finished channels were cleaned-out of the final "Blue Foam" debris with a small Shop Vac.

All done inside with no mess.

The main operating feature on the pike is the unloading/loading siding that is elevated above the mainline.

The approach to the upper unloading deck is Woodland Scenics 3% Incline/Decline set.

The entire upper section is layers of compressed foam insulation board. The board itself is a 1/2-inch, 4'x8' sheet. With an aluminum foil backing on one side.

After removing the foil backing I cut the board into 6"x48" strips. Since the height of the upper section was 3-inches I simply stacked 6-layers.

I used yellow carpenters glue to bond the layers. I weighted the entire length of the laminated strips and allowed it to cure for 24-hours.

Because of the clearance necessary for the MU of four GP40s I needed to carve out a shelf under the unloading platform above.

Initially I used a mat knife to carve out the rough-work and made the final shapes with a SureForm® blade to smooth out the walls.

While carving out the shelf the yellow glue had completely set!

It had a bond strength greater than the surrounding foam; from samples removed from the rough-work.

This was all done outdoors because of the mess created by the compressed foam board.

Hope this helps.

"Uhh...I didn’t know it was 'impossible' I just made it work...sorry"

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Posted by rrebell on Sunday, January 14, 2018 11:05 AM

Attuvian

All,

I searched for a thread on this subject but couldn't find one right off, so . . .

For the last seven or eight years I've collected a tidy amount of styrofoam used as packing for furniture kits and other items.  Thought that it might make an appropriate foundation material for hills, other scenic items and who knows what else.  Most is in sheets of varying thickness but I also have some modestly sized blocks.  Most of the stuff has a relatively fine "grain" and is a bit more dense.  Some is a bit more coarse and can create a small snow storm if handled roughly.  I'm imagining that Gorilla glue or another common adhesive will do to aggregate it according to need and design.  I'd like to make use of it as disposal will be a pain in the neck - or elsewhere.

I expect that there will be some amount of "fluff" producted in the cutting and sculpting of it.  Not sure I want to pony up for some hot wire cutting gizmo that might be out there.  I'll just have to keep a small vacuum handy as I have at it with blades or whatever.

Except for the down side of the chaff produced, are there any other liabilities for this use of styrofoam?  And while we're at it, once it's been contoured, what materials and techniques are best for surfacing it in preparation for grass or other applications?

I will not be using it for rocky outcroppings, cliff faces or anything else that will require finer surface detail.

I know that there's a lot of current chatter on the forums about pink foam.  But i'd like to get rid of this stuff first.  And so would my Sweetie!

Obliged, as always.

John

 

Ok, most have not built a full layout with beaded foam and scraps, I have and it was 15x30 dogbone with yards. Build your 1x4 frame work and use bought foam of uniform thickness for the first layer that you will put track on. Make sure it has srunk as fresh foam shrinks when first made but after 3 months you are fine and most stuff in stores has already shrunk, to find out measure it against the size they say, real measurement should be smaller by about 2% in length and width. You can caulk it to the wook along with all the other layers you will use. To cut the stuff that you can't cut with the hot wire I used a blade at times or a saw. Secret to stoping the little flyaways is to do the bulk cutting outside. Toxic gas is real with a hot wire but if you use Woodland Scenics stuff you don't have to worry as theirs is tempeture limited to never get to the right temp. to reliese the gas. You can glue your cork right to the foam. Now you have to seal the foam in some way and I chose plaster cloth. You can buy it fairly cheap in bulk and since you are just covering up the exposed surface for the most part, it goes along way. Plaster cloth is not messy if you handle it right. To make rock outcropings and stuff, take your mold and paint the inside with hydracal and then put in plaster cloth and coat again, this will make a very strong detailed but lightweight casting that is easy to caulk in place, then use regular plaster to fill in any gaps but wait till the caulk has cured enough so the casting dose no move and don't forget to spray the area first so the plaster will stick.

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Posted by mbinsewi on Saturday, January 13, 2018 10:14 PM

John, your prices are right in there.  In SE Wisconsin, my local HD has 4'x8'x2" for $27.54 and 1" for $19.98.

Kevin!  Wow, you can buy this in Florida?

Mike.

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Posted by Attuvian on Saturday, January 13, 2018 7:35 PM

SeeYou190
.

Much to my surprise, when I was in there last week, there were 4 by 8 sheets of pink foam in 5/8", 1", and something about 2" thick. First time I ever saw it there.

-Kevin 

Just got back from H/D.  Ours had a 4' x 8' x 2" sheet for $29.00; a 4' x 8' x 1" was $18.95.  Sharp knife cuts it far better than the standard white stuff.  One sheet of either would fit my needs.  Kinda feels like I'm trading new turnout for a mountain.

John 

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Posted by SeeYou190 on Saturday, January 13, 2018 5:01 PM

I have been frequenting Home Depot a lot more with all the work I am doing on the kitchen.

.

Much to my surprise, when I was in there last week, there were 4 by 8 sheets of pink foam in 5/8", 1", and something about 2" thick. First time I ever saw it there.

.

All measurements are approximations.

.

-Kevin

.

Living the dream.

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Posted by Bucks County Extension on Saturday, January 13, 2018 4:51 PM

We've used Styrofoam on our layout in conjunction with blue-board, all leftovers from shipping and construction. Styrofoam has been fine for everything that was NOT AN OUTER surface.

- Lower levels to build layers of styro under hills and high points

- invisible tunnel interiors

- under structures where buildings & sidewalks cover

Outer layers that were scenicked then sit atop the styro base. All laryers bonded with construction adhesive in caulk gun for large areas or Liquid Nails from tube on detail areas.  After 5 years, no problem.

Sounds like you are planning to go this way & should be fine.

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Posted by mbinsewi on Saturday, January 13, 2018 3:55 PM

I'm sure that coming from Portland, you shouldn't have any problems finding the extruded foam (blue and pink board).

I've learned from these forums, that our friends in the warm states, don't have access to it. Which baffels me, as it's used in many construction applications.  The backing for exterior stucco and plaster finishes, and under cold storage building floors.

I used the extruded, and stayed away from the expanded bead board.

Mike.

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Posted by Bubbytrains on Saturday, January 13, 2018 2:08 PM

I think the advent of using styrofoam (not the white beaded packing stuff, mind you, but the flat insulation sheets) for model railroading was a huge step. Relatively cheap, wide variety of uses, fairly easy to work with, goes a long way,  and very forgiving. I mostly find the pink stuff at my HD. 

Downsides: 1) be careful you don't use any solvent based paints or adhesives, which corrode it badly. 2) creates lots of very messy chips and flakes when using rasps or knife-edges to create irregular forms, and the chips are static lovers. You absolutely need a good shop-vac handy!

 

Bubbytrains

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Posted by Attuvian on Saturday, January 13, 2018 1:05 PM

Robert and Overmod,

Well, that does it. Styro-flakes threatening my socks, underwear drawer and tender parts tipped the scales. Guess I'll have to chuck the furniture packing. Don't want to have to 'splain away the unforeseen consequences of using it to the little lady. Embarrassed

John

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Posted by Overmod on Saturday, January 13, 2018 12:22 PM

I'm not sure why anyone would still be chipping and cutting away at Styrofoam, either as underlayment or surface forming, when even commercial hot-wire tools are under $20 and it's reasonably easy to 'gin your own up with appropriate Nichrome.  MUCH cheaper than, for example, a Shop-Vac setup at your elbow and all those bags you'll need to contain the flinders...

If you must use the Shop-Vac approach I'd recommend using one of the Surform style 'multiplanes' for shaping, instead of hacking away with tools that have raked teeth.  Your socks and, ultimately, various tender parts of your body will thank you in the long run...

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Posted by ROBERT PETRICK on Saturday, January 13, 2018 11:26 AM

Attuvian

On some metaphysical level, justice prevails. 

Ain't it the truth! Speaking of which . . . that sound you won't hear will be me chuckling when you're sitting there wondering how those millions of tiny styrofoam flakes managed to infect your socks and underwear drawer.  Laugh

LINK to SNSR Blog


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Posted by Attuvian on Saturday, January 13, 2018 10:28 AM

ROBERT PETRICK
 
Attuvian

Did you ever manage to get your car into the detached garage that you built? Wink 

 

 

Umm . . . no. Embarrassed Still parking in the driveway. I guess that's what you might call ironic.

Robert

 

Robert -

Yes!!  On some metaphysical level, justice prevails.  The weekend is better already.

John

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Posted by ROBERT PETRICK on Saturday, January 13, 2018 8:59 AM

Attuvian

Did you ever manage to get your car into the detached garage that you built? Wink 

Umm . . . no. Embarrassed Still parking in the driveway. I guess that's what you might call ironic.

Robert

LINK to SNSR Blog


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Posted by eaglescout on Saturday, January 13, 2018 7:18 AM
I've used the white styrofoam underneath the pink or blue foam to build up mountains. I shy away from using it as a top layer due to the much mentioned and experiences snowstorm effect.
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Posted by Bayfield Transfer Railway on Friday, January 12, 2018 11:48 PM

Ventilate, ventilate, ventilate.  The fumes from beadboard are way worse than the pink or blue styrene.

 

Disclaimer:  This post may contain humor, sarcasm, and/or flatulence.

Michael Mornard

Bringing the North Woods to South Dakota!

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Posted by Attuvian on Friday, January 12, 2018 10:55 PM

Good stuff, Robert. Maybe I should price out some of the pink and blue stuff, especially if it's easier to work and won't create a blizzard.

BTW, earlier today I saw your string of posts that displayed the benchwork progression of your move into your attached garage. Really nice craftsmanship. Did you ever manage to get your car into the detached garage that you built? Wink

John

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Posted by ROBERT PETRICK on Friday, January 12, 2018 9:13 PM

I use the pink stuff, the blue stuff, and the white pebbly stuff. Everyone is right, the white pebbly stuff scatters into a million pieces. You need your Shop-Vac standing by. The other thing is that all three generate static electricity, and that makes it difficult to throw them away. Those little bits and pieces and thin slices are so light and so clingy that you'll end up looking like a Buster Keaton movie.

I have some old pink stuff and some new pink stuff. The old pink is a little more crumbly and the new pink is a little denser and more uniform in texture and it carves like deli meat. I use a razor sharp 7-inch fillet knife and a 3-inch X-acto flat blade, also razor sharp. I've used the hot wire before, but that is a little difficult to control. I don't own one (I borrowed one), and I suppose with practice you can get pretty good at controlling it. After the big pieces are glued into place, then you can shape it with a rasp or coarse file or chisels or serrated knife or rough sandpaper (I have some 20 grit) or whatever.

For glue I use acrylic ceramic tile mastic. It is a little thinner and a little fluffier than caulk. A one-gallon bucket cost about $12 at the big box stores, and it contains about as much as 20 or 30 tubes of caulk. Spread it on evenly like peanut butter with a putty knife or use a notched trowel. You don't need very much. It holds in place instantly and takes a couple of hours to firm up. It makes a very good bond. I've used white glue and yellow glue, but the structure of the rigid styrofoam is made up of closed cells that keeps air out, and it takes literally a week for those glues to dry.

Robert

LINK to SNSR Blog


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Posted by SeeYou190 on Friday, January 12, 2018 9:06 PM

Bundy74
2) I used gorilla glue at work for a foam project. It's very strong, and is also gap filling. The molds I made had gaps between the layers, and the glue flilled them well.

.

Gorilla Glue makes a fantastic bond between foam sheets, but keep these in mind:

.

1) Gorilla Glue expands when it dries. The foam must be clamped together or it will be pshed apart.

.

2) Hot wire cutting tools do not like contacting Gorilla Glue.

.

-Kevin

.

Living the dream.

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