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Styrofoam - Any Negatives?

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Styrofoam - Any Negatives?
Posted by Attuvian on Friday, January 12, 2018 5:11 PM

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

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Posted by dknelson on Friday, January 12, 2018 5:23 PM

I have used some styrofoam, the white beadboard kind that is pretty messy to cut but can be shaped neatly using a hot knife or hot wire tool -- in a WELL VENTILATED space, preferably outdoors.  The smell is considerable and unpleasant, so warn others in the house beforehand.  Do take precautions.

It doesn't take long to learn how to make the shapes and contours you want, and I am very happy to use it.  I model the midwest with mostly gentle rolling hills not mountains.

What I like is that you can experiment with little risk.  Does the hill look too high?  Use the hot wire tool to lop off the top.  Change your mind?  Glue that piece back on.    

Woodland Scenics offers their own line of the stuff, in a large selection of thicknesses, rather more dense and less "beedy" than the usual packing material you can get "for free."  

Woodland Scenics's Foam Tack Glue works well on all kinds of styrofoam in my experience.  

Dave Nelson

 

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Posted by Bundy74 on Friday, January 12, 2018 5:42 PM

1) I use knives and saws to cut foam shapes.  Keep your shop vac handy, and perhaps wear a dust mask if you're gonna get crazy.

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.

3) As for surfacing, you can simply paint it with latex paint if you're going to use ground foam.  Or you can add a thin layer of paper mache or plaster cloth.

4) I'd suggest using the pink board for the subroadbed, then the white beaded chunks for hills, etc...

Modeling whatever I can make out of that stash of kits that takes up half my apartment's spare bedroom.

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Posted by RR_Mel on Friday, January 12, 2018 5:48 PM

I built my mountains with the type that creates snow storms and have been happy with the results.  It is messy but super strong.  As with most Styrofoam you have to use the proper glue or it will melt.
 
I covered the carved Styrofoam with Paper Mache and wouldn’t recommend it because it shrinks as it dries.  I learned through the process by covering the Styrofoam with plastic wrap first prevents the shrinkage from screwing up the Styrofoam.  After the Paper Mache has fully dried remove the plastic wrap and glue it in place, that works very good.
 
The guys on the Forum put me onto Sculptamold and it works very great, much better than Plaster of Paris or Hydrocal for ground cover.  For rocks I use Woodland Scenics rock molds with either Plaster of Paris or Hydrocal cemented to the Styrofoam with the same.  I bought a cake decorating applicator for applying plaster or Hydrocal as the glue to hold the rocks and fill in any gaps between the rocks.  Don’t let the plaster set up in the cake goodie or it’s a goner.  I keep a bucket handy to dunk it in before the stuff sets up.
 
 
 
By inverting and cutting the castings of several rock molds you can make a pretty large rock scene without all the rocks look alike.
 
 
Have fun!
 
 
Mel
 
Modeling the early to mid 1950s SP in HO scale since 1951
  
 
My Model Railroad   
 
Bakersfield, California
 
I'm beginning to realize that aging is not for wimps.
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Posted by Attuvian on Friday, January 12, 2018 6:12 PM

Thanks, Dave, Bundy and Mel. This is a good start.

John

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Posted by UNCLEBUTCH on Friday, January 12, 2018 7:12 PM

Foam is all I use for table top and landscape,all mine was reclaimed from the dumpster. I stay away from the beaded stuff because of the excess mess, and the fact I have so mutch of the pink and blue.

 

I glue mine together with plain cheap caulk. To cut; score with a knife and snap. Any kind of sawing is more mess to clean up. I cover mine with drywall mud,in case of a joint, use drywall tape over seam.Smear the mud on,work it with a water wet brush. You can carve the mud or foam with any thing sharp and pointy.Myself I wouldn't spend money on any kind of ''hot knife''. You'll use it a few time and then it sits.

I just tore down my layout and the tape/mud joints were stronger then the foam.Had planned to reuse what I could but found a pile of nice clean stuff. 

The only neg I found was mounting the ground throws for turnouts, Now that I got that figured out, no problems at all.

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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

.

Happily modeling the STRATTON & GILLETTE RAILROAD located in a world of plausible nonsense set in August, 1954.

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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

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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 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 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 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

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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 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

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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 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 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 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 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 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

.

Happily modeling the STRATTON & GILLETTE RAILROAD located in a world of plausible nonsense set in August, 1954.

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  • From: Portland, Oregon
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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 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 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 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 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 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 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 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 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 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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