Pushing the limits

Bart, 1" will transmit noise, even with a soft adhesive, and roadbed. I have two areas where I used 1" to bridge a short area, and maintain clearance below for trains. Both areas are less than 24" long, and supported every 6" underneath. There is a noticeable difference in sound when locomotives go over those spots, slow or fast. All the rest of my layout is 2" foam only on 1 X 4 benchwork attached with adhesive caulk, with WS foam roadbed attached with Matte Medium, with no noise transmission.

Now...is it objectionable ? Hmmm...I can tell exactly where those spots are when running sound locomotives...but other operators I have asked say no...they don't notice it...so is it just me ? I would suggest making up a small module...just large enough to get your locomotive over it say...12" X 24" ? Glue everything down, let it dry, and see what you think. It may be worth the experiment to find out before commiting to a complete layout. Is there a reason you do not want to use 2" foam ? Cost ? Dimensional challenge ?

Michael

1" is loud

75% of my temporary layout is open grid with1" foam... It's very loud compared to the section that is track on wood. Well more then twice as loud

Wait a minute....

Don’t most railroad engineers and conductors retire with diminished hearing???  Shouldn’t the noise only be 1/87th the level of the 1:1s.  

What was that???  Say again????

Nick

Yes it will be noisy.

Simple answer is, yes.

Foam Noise, Again

Thank you, Michael for your reply.

If I understand you correctly, you DO experience noise with one inch unsupported (other than the usual grids, I assume) foam but you do NOT experience noise with two inch unsupported foam, correct?

To answer your question, cost of one inch foam vs two inch foam is the reason for wishing to utilize one inch foam.

Bart Chasley

Foam Noise, Again

Thank you, Bob.

Bart Chasley

Foam Noise, Again

Thank you, Multilevel.

Bart Chasley

What I noticed on my layout,

What I noticed on my layout, with homosote glued to 1inch foam glued to hollowcore doors, it is much quieter than homosote glued to plywood; though I was never aiming for quiet; just going for lighter.

Yeppers

That is correct Bart. NOW...let me qualify that, I did a mock up using 1 X 4's made into a 12" X 24" box. In fact..I made a bunch of those rectangles. I tried a variety of glues and adhesives and a variety of foam... 1/2", 1", 1.5", and 2" foam. Then I started my search for roadbed.... cork, homasote, foam, camper tape, that black adhesive stuff that looks like roadbed...well...I got all that I could find that I liked. After all my trials, tribulations, and testing, I came up with using Liquid Nails Project caulk, applied in a 3/8 " bead. I then laid 2" foam on top of it, weighted it with paint cans, tool boxes, airbrush compressors, etc., and checked underneath that I had squeezed out the adhesive evenly. I then let it dry for 2 days...checking the bead to verify that it was dry. I laid this completely around the dimension of the layout for a base ( I wanted the opportunity to go below grade with ditches and pits etc. if I wanted to ). Next I used WS inclines for my transitions from low to high, glueing those down with MATTE MEDIUM. My previous tests showed that good old Elmers transmitted noise like crazy...because it dries hard. Matte Medium stayed plasticy ( ??? ) and kept noise down. Next was the WS foam roadbed, again...applied with Matte Medium and pinned to the foam, giving it several days to dry. Track and switches...same thing...glued with Matte Medium. Now...as I changed things, I have had to compromise and make additions and corrections from my original plan...and I have used all of the above sizes in my corrections. There is NOTHING I can do to make the 1/2" foam quieter. The 1" foam I have improved noise transmission by cross bracing underneath. I have yet to try adding spray foam or that spray insulation. So far, it is one of the areas I know about but it doesn't seem objectionable to anyone else. The 1.5" foam is just as quiet at the 2" foam, no difference.

Oh...one more note...it doesn't make any difference if the foam is Pink, Blue, Purple, Yellow, whatever. I have used them all....they are all exactly the same.

The only other suggestion I can give you Bart is to buy a Kreg screw system. I know it is expensive, but it makes excellent VERY tight joints, whether it be end joints, butt joints, 45's....and you will find you might become a cabinet builder as a bonus !

Michael

If you have a moment

you could approach the sound engineers at Bose and get a noise cancellation system for modular model trains.  All you would need is a speaker on the bottom of the module, a microphone, a black box and some power......  Maybe we could get Dr. Geoff onboard so he could make a fortune with the design too.

Nick

Yes, but . . .

I LOVE this discussion.  I can't tell you how long I agonized over it.

Simple answer is, yes, it will be a little louder than other methods.  BUT, my entire layout is built of 1" foam over a grid benchwork.  Here's why . . . 

1. It's light and easy to work with.  Cut it with a knife, little mess, no saws and sawdust in the layout room.
2. It's EASY to make nice smooth grades
3. It's EASY and quick to install with a hot glue gun.  Risers are simplicity itself.  Simply cut the million and a half little scraps into usable shapes and glue them in place to support the roadbed.
4. It's EASY to cut variations and undulations in the surface to avoid that flat, table top look.
5. It's EASY to plant trees.  Just stick 'em in the foam.
6. It's EASY to cut out rivers, lakes, drainage ditches, road underpasses, etc.  

Did I mention it's an easy material to use?  On top of all this, once you apply ground foam, track, roadbed, structures, trees, etc. it quiets down.  I've also found I can quiet it more by gluing wood runners under the track itself when I'm all done with wiring and switch machine installation, although I haven't done that except in tests.  That's because once I got areas all scenicked, I stopped noticing any noise.

All my locomotives have sound, and I can still hear it.

Just my opinion.  Your mileage may vary.  

Here's an experiment...

Hold a chunk of foam up to your ear, just supporting it lightly with two fingers. Now rap on it with a finger on the other hand. Hear the "ping"? The foam itself is resonant (one of these days, I'm going mic a bunch of pieces to make a percussion instrument). You have to avoid exciting this resonance by soft coupling the track through layers of various density road bed (WS foam over steel works well) or dampen it by gluing the foam to something solid. The effectiveness of the damping is related to the percentage of foam surface glued to a support. The best approach I've found is to glue the foam to 1/4" plywood. This has an added advantage of providing a solid base for switch machines and the like.

If you go the soft coupling route, the evil is in the ballast glue. Elmer's is OK if it does not bridge the gap to the foam. Otherwise, that spot becomes a mallet. Some have reported good results with matte medium.

pqe

Magic Carpet!

Well not carpet but drapes!  Worked on a layout that no matter what we did we had a few areas that produced noise.  HOWEVER once we had the fascia on and hung some light weight drapery material under the layout, that noise just melted away.  What you are making is a very large drum.  Some areas are bass drum like, other areas are snare drum like.  The sound is mostly coming from UNDER your layout not from the top.  The drapery will cut down on that 'bottom' noise transmission.  Russ

I used one inch pink foam on

I used one inch pink foam on open grid structure for my garage layout.  It was loud from the beginning but as I added scenery, structures, facia and fabric the noise has been reduced greatly.  Of course, I have nothing to compare the noise with but with sound engines, steam and diesel, I forget about any unpleasant racket.  Your study examples should help future model railroad builders, thanks for sharing.  Gale

1 inch foam.

My entire layout is 1" pink foam, on an open frame benchwork (except for the middle, which is a solid bookshelf top, but with 1 inch wood risers, to allow spece between the foam and the solid wood top)

I use EZ track, which has plastic roadbed attached.

Recipe for disaster, and ear protection?

You would think so, but, my layout is actually quieter than the layout at the San Diego Museum (and that layout is pretty damn quiet)

You should be fine.

Oh, I should add...

My scenery is Durham's water putty in various thicknesses all along my layout, with some thick cardboard in thge areas where I needed the ground a bit thicker around the roadbed, and all of my track is ballasted with a combination of washed beach sand (de-ironed with magnets during the wash process to get otu the salt) and Arizona Rock medium ballast mixed.

Correct ! Great discussion

It is good to hear from eveyone that is using foam, and the various thickness's. I am interested in Gale and Michael A. comments on the additon of scenery actually helps quiet it down. I am just now getting to adding the hills and mountains on my layout, but I wish I had paid more attention as I was adding static grass and other ground cover to see if that improved the transmission of sound....

Michael

My little "around the walls"

My little "around the walls" layout is 2" foam directly glued onto an open plywood frame.  I have foam noise and actually like it - but then I run my trains slowly (around 30 mph scale speed).

@ Rick

Hi Rick,

i was wondering today if someone took some carpet or something similar and attached it to the bottom of a foam reenforced with plywood structure the “noise” would be significantly diminished.  

Too much time on the road thinking about things.....  also didn’t use foam.....

Nick

I am cuurently building a new

I am cuurently building a new layout using  1" and 2" foam over 1/4" sureply underlayment on open grid. I have done some testing and I will be glueing a layer if 1/4" cork on the ply and then the foam, also using cork roadbed. I find it is nearly as quiet as my old layout with foam over homosote and much lighter. This layout is hung on HD shelf brackets 32" o.c.

Bart if you are concerned

Bart if you are concerned about noise levels why not just add a layer of Masonite or thin plywood under the foam?  Cheap and easy insurance. The majority experience here on the forum seems to indicate that would help reduce noise levels  +1 on having a solid surface to mount infrastructure like terminal blocks  

Personally I have 1 inch foam over Masonite  over steel  studs, all gorilla glued together and sitting on shelf brackets. I find the layout to be very quiet

jeff