I thought that the pink extruded foam was supposed to absorb sound or at best be a lot quitter then the blue stuff. I have one of two hidden staging yards which have good old homasote bases but the one exits to a section that is lets say a transition area up to the first level of track and man this stuff is just as noisy as plywood. I realize that is I glued cork roadbed on the foam and then glued the track to the cork it would absorb a lot more noise but I have had countless people tell me you can just glue the track with either yellow carpenters glue, white glue or Liquid nails straight to the foam. Am I missing something here?
All I can say is: Don´t! I have experimented a lot with pink foam in layouts for an article in a book, and the results with tracks directly on the foam was very audible. If I used cork or foam (WS) roadbed it was much more pleasing to the ear. I did however try to minimize the resonating effect in the pink foam by glueing sleeping pad material on the underside of the foam-sheets and it also helped.
Acrylic silicone adhesive caulk might be less noisy since it has some spring to it.
Skip the silicon and go with latex caulk. It’s usually cheaper, plus it doesn’t stink. Definitely no glue that sets up hard, like yellow glue or liquid nails. Also, what sort of support does your foam have? My previous layout was 2" pink foam on top of an open grid of 1x4’s, crosspieces on 2’ centersThe foam was glued down with yellow glue, and I used WS foam roadbed glued down with latex caulk, and used caulk on the track. This combination was quite quiet. I built one section for a new layout but wwanted to set the foam in a bit, so I used 1x4’s for the long side with 1x3’s for the crossbraces, at 2’ centers. When I set a peice of foam in, since it only touched the cross pieces and was inside the longitudinal pieces, it seemed awfully noisy, so I picke dup a coupel of cheap 1/4" 2x4 plywood handi-panels and screwed those in, then glued the foam on top. Quiet.
–Randy
Hmmm I never heard that. Both are extruded foam. I’ve always thought they were exchangeable.
Yes, you can, but as you noticed it is noisy. The larger the area the foam spans the noisier it is. It acts like a drum head. If it is a large expanse, you could add a couple more supports and it might reduce the drum resonance effect. I seldom put the track directly on the foam when it is the supporting structure in addition to being the sub-road bed.
No.
I am using 1x4 open grid bench work and the foam where I used it is glued to the bench work with Liquid nails it is glued down to the foam with 50/50 white glue & water. The entire length is maybe 8 feet long give or take. I originally was not going to have a lower level but then decided on hidden staging another not so good choice so I created an approach to the hidden yard with the pink foam. Once again I listened to a friend who swore up and down that this works very well etc. etc. yeah well so much for that. The suggestion of using latex caulk maybe a solution or I take up the track which in it self is no big deal and either put it on cork roadbed or go back to using good old messy homasote. I was running trains breifly tonight and as many years as I’ve used the stuff I still can’t get over how quiet homasote really is. Even my wife noticed it so much so she said you know the second
Allegheny,
I’m with Randy on the latex caulk. I buy the DAP Alex Plus Acrylic Latex Caulk at Home Depot. Some of the big advantages for me:
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$2 per tube
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Very little odor and safe - Some of the other adhesives like Liquid Nails have some pretty nasty chemicals in them.
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Quick set up time: 40 minutes - I let it cure overnight and lay bricks on top to make sure that everything is flat.
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Holds very well and remains flexible - Unlike white or yellow wood glue that dries hard.
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Modifications or changes to track plans can be made by simply and gently prying up the track and/or cork roadbed with a wide spatula.
I use it for foam to foam, foam to styrene, foam to cork, and cork to track. Great stuff!
As far as noise is concerned, I find that the foam and acrylic latex caulk is quieter than plywood - even with all metal wheels.
Tom
We have a layout in our group that used pink foam, but he put down camper/truck topper foam tape down first as the roadbed and its very quiet verus cork or straight on it
Anybody try using “fluffy” foam bats under the framework? I mean the synthetic polyfiber pillow fill. Seems to me that if the foam over grid is acting like a drum head, that might be one way to muffle the drum.
Just musing; I use 2-inch foam on shelf brackets directly or laminate layers to doorminoes.
All disclaimers apply
I added 1/4" luan plywood to 1x3 frame on 16" centers (because of poor adhesion) and that helped quiet the 2" pink/blue foam sheets. Sections are 2’x8’, 2’x6’, and corner “L” shapes 4’leg and 6’ leg. I used WS foam sheets which quieted down Kato Unitrack.
Sections are sitting on adjustable wall brackets around the room and plastic ventilated shelves for the peninsula. Sections on wall brackets tended to be louder with resonance off the walls, shelf above, and bracket risers. I could not get the sound of my LL Pere Marquette 2-8-4 down to an enjoyable level.
This current layout is now on hold while building a new HO-scale railroad for the Charleston Area Model Railroad Club in Charleston, SC. 40’x 16’ sectional using 1X4 plywood frames with 5/8" plywood top, 1/2" Homasote sub-roadbed, and WS Foam roadbed. Very quiet.
Sounds to me there Allegheny2-6-6-6 that you are making a perfect argument for using cork for roadbed!
I think Steve, at Railway Engineering, has it right. Here’s what he had to say about the subject:
"If you intend to ballast your roadbed … and use wood glue … then the sound gets transmitted around the cork anyway. Everybody who says the foam is or isn’t quiet, is only judging by unballasted roadway. I’ve tried all the corks and stuff … 50 years worth… I’ve seen cork … homosote … upson board … celutex … tar (AMI) etc . etc … They all make noise unless … you use matte medium …(latex glue) to fasten the ballast. Latex contact cement to attach the track to “whatever” and then matte medium for the ballast, is the quietest that I’ve ever heard or seen. Most people build with plywood, and that is the noisiest. Sounds like a big piano sound board… cork or no cork. Plywood has to be cut no bigger than the track itself or excess noise is the result.
Glued ballast atttached to hardshell scenery, is also a large sound board. The newer plaster gauzes do a better job of “killing” the sound.
-Steve "
http://www.railwayeng.com/rrhints.htm#q22
Allegheny2-6-6-6:
I thought that the pink extruded foam was supposed to absorb sound or at best be a lot quitter then the blue stuff.
Hmmm I never heard that. Both are extruded foam. I’ve always thought they were exchangeable.
Blue foam and pink foam are exactly the same thing. Blue is made by Dow and pink is made by Corning (company colors).