Tracklaying on Foam

[Anonymous]

With extruded foam board, what is the best type of adhesive to use for laying flextrack and turnouts?

[Anonymous]

I doubt its the best way but i have just been using brad nails which are long enough to go through the track and roadbed into the foam board enough to hold it tight in place. i think i may start using glue as well as the nails in the future.

[orsonroy]

Nails won't work; the foam isn't dense enough to hold any sort of nail or screw.

I've used several types of adhesives to lay track. Some work better than others. Until recently I had settled on wood glue, since it was what I was using to glue foam together. I've since discovered that clear silicone caulk adhesive works MUCH better. It's cheaper than wood glue (considering how little you use), makes a nice tight bond that's workable for about 1/2 hour, and dries clear. It also acts as a sound deadener better than anything else I've found.

Using caulk is simple. Mark your track centerlines (or outside edges) onto the foam with a marker, use a caulk gun to add a small bead of caulk along the length of track you want to lay (only work up to 9' long at a time, of the caulk will start to dry out), smear the bead into a thin, even layer with a trowel, and add the track. Once you get the track into it's final position, hold it to the foam with push pins (which can be removed after an hour or so)

No matter which adhesive you use, try NOT to glue down your switches. I only add a VERY little at the ends of mine, to tack them into place. If you glue too close to the moving parts of a switch, chances are good that you'll glue it in place, ruining it.

[Anonymous]

remember to check and see if the caulk is safe for foam if not it will eat holes where ever its applied. good luck

[orsonroy]

All silicone caulk is safe on foam. What you're thinking about is construction adhesive like Liquid Nails or Pliobond. THOSE aren't caulks (although they come in caulk gun tubes). And yes, definitely be careful about which construction adhesives you use on foam.

[trnjlc]

I am new to this site but have been experimenting in laying flex track using spay on cement called Super 77. Works great on cork and assume it would also work with foam. We had been using Liquid Nails for laying flex track whick works well but makes it very difficult to remove. With Super 77 removal is much easier.


Jack C.

[orsonroy]

I tried the 3M spray adhesives (both the 77 strength and the 90) and will never use them for anything again! Yes, it's a fairly fast way to lay track, but as an adhesive it's no faster to lay than wood glue or silicone caulk. And the bond is very weak, which will give you lots of headaches WHEN (not if) the wood of your benchwork expands/contracts due to humidity fluxuations. On my last modular layout, I ended up with a Hot Wheels track for a mainline, because the glue didn't hold when the (sealed) wood expanded!

Using solicone caulk will allow you to (relatively) easily move track if you need to, but it will still give you a stronger hold than spray adhesive. And it's cheaper too!

[simon1966]

I used liquid nails foam compatible adhesive and caulk. Both worked fine. I would recomend peeling off the plastic film on the board before adhering the cork roadbed, if used, or the track. I found that where I had a curve in the cork that over time the plastic film lifts off the board under the turn and the track shifts.

[Anonymous]

Thanks for the help!

Sounds like I can use silicone caulk adhesive on the track-to-foam yards and on the track-to-cork-to-foam mains... avoid gluing switches...

Thanks!

[BuffaloBob]

Thinking of using foam on new layout, have experamented with foam in the past on moduals and used spikes and wood glue seemed to work, had no problems for six years and many shows and moves. My question is when glueing balast, how good is the bond?

[memsd]

If you guys are attaching the track directly to the foam board, are you shaping your own roadbed?

[orsonroy]

I am. I'm actually cutting my own roadbed out of 1/2" thick foam (1.5" wide strips, two per track, 128 linear feet of roadbed for $6), gluing it and the track down, and then beveling the edges with a sharp knife. I then use a Surefoam rasp to add drainage ditches to the sides of the roadbed, and to blend everything together. So far, so good!

[Anonymous]

I plan to use cork roadbed for the main and put the sidings and yard directly on the foam. Thing is, I can't find extruded foam ANYWHERE!

I've been to Lowes and Home Depot and the best they have 1/4" thickness... no building supply stores in the area even carry foam! Maybe this is the challenge of South Florida living... no need for insulation!

[Anonymous]

Hello,

I hope this might help. Check with places that do house siding, a lot of them put it on houses under the siding as a moisture barrier. You might also check and see if there are any Insulation installers around, they might not have it but maby they can order it. You can also go by your local sears and see if they can tell you who they use to do there siding. Or as a last thought a brick company. Check out you phone book and give them a call.

Hope any of this can help.
GreenIron

[Anonymous]

FOUND IT!

Dumb luck played into it, but I found 2"x4'X8' sheets at a building supply place today... $28 each.