sub-roadbed

I'm certainly no acoustic expert Tom, but I can't help but wonder if all the pegboard holes would actually let more noise out from under the roadbed? Only way to know is try a piece.......

I'm not either which is why I'm asking for opinions.  That's an interesting take, D&H 65.  My thinking is based on the idea that a plywood sheet is like a drum head and actually amplifies the sound.  I do know that multi-faceted surfaces reflect less sound.  Also, there is the example of acoustical tile ceilings with all the little holes in it.

This is also for a temporary Xmas layout, so I’m looking for something quick, easy and storable.  I plan on using EPS (white bead board styro) risers.  What I did last year was too labor intensive, unstable, and fragile – that is out.  On the other hand, maybe grades on a Xmas layout is over the top...

Tom Stoltz

There are two elements involved: 1) the surface that acts as a diaphragm--which is eithe the plywood or the peg board--that pushes air based on the diaphragm's ability to flex; and 2) the reflective surfaces that receive the sound waves from the air and either reflect or absorb them. Plywood is tightly bonded wood particles, and the "ply" indicates its pliability or flexibility to act fairly well as a diaphragm. Peg board is made of smaller particles pressed and bonded together. Although the multiple holes will reduce the amount of air pushed slightly, the material itself is more deadened than plywood and somewhat less likely to conduct noise.

Once sound has spread out from a source, acoustic tiles--also made of "deadened" material--have the holes to deflect air pressure and reduce reflectivity of the sound waves. (My father was an architectural engineer who had installed acoustic tiles in a school ceiling in the early 1960s. He explained to the janitor that the holes "absorbed the sound" to make things quieter. The janitor's face lit up in rage: "How the **** am I going to clean the sound out of all those ****ed holes every day?" That's a true story.)

What a great story, thanks Terry.  Your explanation makes me think it is worth a try.  Still, if it really made a difference, I would think someone else would have tried it already.

Tom Stoltz

I do not think we need to get into a lot of theory here, It is S and not O gauge, and the SHS S Trax is by nature quiet. For temporary Christmas layouts I use a 1/2" plywood base. properly supported it does not flex at all unlike particle board. On top of that I attach 1/2" white foam insulation using 2 sided carpet tape. No nails into the plywood, no sound transmission and I have a great scenic base for a snow effect. I similarly attach the track with a 3" long piece of 2 sided carpet tape under each track joint. Built this way the layout can be stood vertically on its edge and the foam panel and track will remain attached to the platform.

To get a grade I just use the same 4' long 1/2" foam sheets, calculate the height every 4' and cut sloped pieces off the edge of the foam using a knife and straight edge. cut two pieces to glue together for a 1" width. For curves carefully bend each piece to the right radius then glue them together, clamp the ends and center till dry. then we have a permanent curve with the right % slope. Glue 2" wide pieces of the same foam to the top of the vertical pieces the use the 2 sided tape to hold the track.

I find this cheap, quick and easy. The result is quiet running trains. I do not recommend this for a permanent layout but for a 2 month Holiday layout I think it is fine. I will post a picture.

Here is a picture of a small layout, no grade, you can see the effect of the styrofoam and tape.

Tom,

I am curious how you bent the ½” EPS. I cut mine like Homa-Bed – notch both sides and left a 1” center that come easily be bent.  However solid pieces wider than 1” would not bend without breaking.  My sub-roadbed EPS was 4” wide. For grades I tapered 2ft long pieces from ½” to 0” using a hot wire knife. – I did make a jig to do the taper.  I stacked the 2 ft long pieces to get the height I needed using tape to hold it in place.  Ended up going around with nails pushed through because the tape didn’t hold well.  It was not very stable – flat and level – and took a lot of adjusting to finally get the trains to run reliably.  As I said before – not again, too much work.

And tape – I found nothing that really worked.  Tape just doesn’t stick to EPS very well.  I must have had ten different types of tape from the hardware store; Duct, Gorilla, painters, several different 2 sided.  The one tape I didn’t try was 2 sided carpet tape.  It was a real leaning experience and have been dreaming up improved methods for the grades ever since.

Covered the whole layout with thick felt and It was very quiet.  That part was nice.

Tom Stoltz

Peg board is made of masonite, which can be quite noisy even with holes.  Foam is always a great way to deaden sound.  I'm in the insulated glass and frame  business and you can never go wrong with foam.  Homasote is also a great sound deadening product but is messy to work with because you have to saw it  and it leaves a mess.  I use it for road bed on top of foam.  Screws transport sound but they are so easy to use in construction so I can't get away from them.   Plastic straps or cable straps eliminate screws but take more time to install. 

Felt would work great. What I bent was only 1/2" thick in the plane of the bend. It varied from 1" to 5" tall. Sharpest bend radius was 25". The layout is on edge in my garage for 2 years, nothing fell off. My Christmas layouts, with one exception have been too small for grades.

Screws or nails through the plastic roadbed into the plywood base will increase noise unless Gilbert track in rubber roadbed is used.

@IRON HORSE posted:

Peg board is made of masonite, which can be quite noisy even with holes.  Foam is always a great way to deaden sound.  I'm in the insulated glass and frame  business and you can never go wrong with foam.  Homasote is also a great sound deadening product but is messy to work with because you have to saw it  and it leaves a mess.  I use it for road bed on top of foam.  Screws transport sound but they are so easy to use in construction so I can't get away from them.   Plastic straps or cable straps eliminate screws but take more time to install. 

Hi Iron Horse,

That’s what my concern with using peg board is.  I was hoping that someone had actual experience with it.  From other train people, I get the impression that extruded polystyrene – the blue or pink foam – is not much of a sound deadener because it is too dense.  The expanded polystyrene – EPS, white bead board – is a great sound deadener however does not wear well if you need to get on it.

I do have experience with ½” Homasote and find it very good.  But find the sheets are not all that flat which doesn’t matter for a more permanent layout.  On a temporary Xmas layout that gets put in storage during the rest of the year, it could be a problem.  Also I think it is getting harder to find.  I don’t mind working with it, would cut it outside.

Tom Stoltz

@AmFlyer posted:

Felt would work great. What I bent was only 1/2" thick in the plane of the bend. It varied from 1" to 5" tall. Sharpest bend radius was 25". The layout is on edge in my garage for 2 years, nothing fell off. My Christmas layouts, with one exception have been too small for grades.

Screws or nails through the plastic roadbed into the plywood base will increase noise unless Gilbert track in rubber roadbed is used.

Let me see if I got this right.  I understand the ½” bend and gluing two pieces together to match the radius, centerline I imagine.  Then you take a 2” wide piece and glue that horizontally on top.  So with the 2” flat piece, is it cut to the radius?  S-Trax is a bit wider that 2”, what happens at the edges?

I’m warming to the ‘spline’ approach for forming the grades in the sub-roadbed.  I think I would make it more like 4” wide, and use spacers, again similar to spline sub-roadbed.  The problem I have is taking it down and storing it.  29” curves take a lot of room.

Thanks for some interesting ideas,

Tom Stoltz

The top piece that goes on the splines is cut to radius.I just let the track overhang the base but it is probably better to make it about 1/2" wider than the track base. I used the 25"R not the 30"R track. I only did this once and the layout was larger than all my other Christmas layouts. With the proliferation of Snow Village in my collection I now leave everything flat so I can get more buildings on the layout. It is not really possible to walk on the styrofoam unless a 2'x2' or larger piece of plywood is put down to distribute the weight. Even then it is easy to leave indents in the styrofoam.

For a simple and practical fix, I too vote for a layer of thick felt. Don't glue it down.  Just place it between the track bed and plywood.  Michaels should have lots of different types of heavy felt, in blacks and browns.

Mannyrock

Thick felt is what I use (see picture), but it has always been used on top of a rug or ½” EPS foam.  What I don’t know is would the felt alone be a good enough sound deadener over plywood.  I also know what I’m not doing again and that is ½” EPS foam as a base because I have to spend too much time crawling around on it.

I’m starting to consider Homasote (440?) as a base that would be covered by the felt.  And maybe I should just bit the bullet and do the grades with the Homasote as well.  But at $30+ a board, for a one month layout.  Probably my biggest problem is dismantling and storing the layout and all its components… I’m not getting younger.

Tom Stoltz

Tom,

Homasote, by all reports, is horrible to cut into straights and curves, and otherwise work with.  (Dust._

If you are not certain that one layer of felts would deaden the sound enough, then just buy enough to put two layers down. It is cheap, easy to cut with scissors, and easy to throw away if it doesn't work out. 

I would staple the two layers together, a half inch or so inside along each side of the outer edges, rather than glue them together.  (Just consider it as a simple experiment.)

Easy enough to do underneath maybe 6 feet of the track, just to test out how it sounds.

Mannyrock

I have used ceiling tiles on my two S-scale layouts, with success. These are the kind that you find in office buildings. They come in a box for 24"x24" sections. Easy enough to cut with a utility knife. I would recommend sealing them with paint shortly after installation as their edges will crumble. It also allows for shaping (will make a bit of a mess). The real culprit with sound is any kind of glue or screws/nails used to connect things together. Anything solid/firm will transfer the sound to the next layer of materials. Ceiling tiles interrupt that transfer. I glued it to my plywood sub-frame and then glued my hand-laid track to the ceiling tile. It's not "silent", but a lot better than installing directly on anything wood. The other advantage over homasote is that you can get ceiling tiles at Lowes or Home Depot for around $10 for a box. Affordable, convenient, easy-to-transport.

Enjoy,

- Peter.

@Mannyrock posted:

Tom,

Homasote, by all reports, is horrible to cut into straights and curves, and otherwise work with.  (Dust._

If you are not certain that one layer of felts would deaden the sound enough, then just buy enough to put two layers down. It is cheap, easy to cut with scissors, and easy to throw away if it doesn't work out.

I would staple the two layers together, a half inch or so inside along each side of the outer edges, rather than glue them together.  (Just consider it as a simple experiment.)

Easy enough to do underneath maybe 6 feet of the track, just to test out how it sounds.

Mannyrock

Mannyrock, You are correct about Homasote being a mess.  I have use it quite a bit and have learned to cut outside.  I do like the results with Homasote and because you can walk on it, I am thinking seriously about using it for my base rather than EPS foam.  I destroyed the foam I used last year and need to replace it.  Homasote for the sub-roadbed on the grades is also probably the way to go.

Because it is a Xmas layout, in the living room, I don’t have much time to devote to testing.  I need to be able to have all the decisions made ahead of time.  But I can say that felt rather than any cotton product is the way to go especially, for the trains, also cotton is not all that stable of a platform for village people or trees.

Tom Stoltz

@PVan posted:

I have used ceiling tiles on my two S-scale layouts, with success. These are the kind that you find in office buildings. They come in a box for 24"x24" sections. Easy enough to cut with a utility knife. I would recommend sealing them with paint shortly after installation as their edges will crumble. It also allows for shaping (will make a bit of a mess). The real culprit with sound is any kind of glue or screws/nails used to connect things together. Anything solid/firm will transfer the sound to the next layer of materials. Ceiling tiles interrupt that transfer. I glued it to my plywood sub-frame and then glued my hand-laid track to the ceiling tile. It's not "silent", but a lot better than installing directly on anything wood. The other advantage over homasote is that you can get ceiling tiles at Lowes or Home Depot for around $10 for a box. Affordable, convenient, easy-to-transport.

Enjoy,

- Peter.

Thanks Peter, I did check the price at Home Depot and the cost per sq/ft is more than Homasote.  Still, that might be offset by ease of cutting, etc.  I wonder how ceiling tile would hold up to being on it during construction.  I would be placing it on top of 1/2" plywood.  It would probably need more support when used as sub-roadbed on grades.

Tom Stoltz

Tom,

The ceiling tile would not hold up to physically crawling on it; it compresses pretty easily when localized weight is put on it. I don't think it was designed for that. You can see my first usage of it on my previous S-scale layout here:

https://www.pmrr.org/Layouts/P...rogressReports11.htm

and in my current layout/diorama here:

https://www.pmrr.org/Layouts/P...e/indexFramework.htm

This also shows photos of the box that the tiles came in (from Lowes).

- Peter.

Wow Peter, nice work and great info in your articles.  I even went to the link for 'ceiling tile roadbed'.  There is a lot to digest and I will have to go back to it when I have more time.  Pictures are a real plus.  Is MDF medium density foam?  And just what is that?  Like pink or blue Styrofoam or something else?  Glue dries between sheets of EPS and I've read it is a problem with the extruded styro.

Tom Stoltz

Tom,

I believe that the MDF he refers to stands for medium density fiberboard.  It is like a very hard compressed cardboard.  Considerable dust when you cut it.  Not very strong, but rigid enough for hobby stuff.   I think you can go to Lowe's or Home Depot and look at a sheet of it.   If it gets wet, it swells and never really dries back to its original thickness or shape.  If it gets too wet, it dissolves.    If you have ever looked at the super cheap furniture that is being sold in places like WalMart, the flat surfaces are often MDF with a layer of thin vinyl veneer stuck on top of it.  You often see it used as the bottom  section of a pull out drawer.   I think when you go see it, you will recognize it. It bends fairly easily.

Mannyrock

Cutting Homasote, I use a Bosch jig saw, fine metal blades and a Shop Vac with a HEPA filter  holding the hose inlet right at the blade.  When done carefully this can be done anywhere.

The other alternative is to use a Airways # 6 flooring knife available at flooring supply stores and HD.

Couple of passes with a sharp blade and you have a clean dustless edge.

Using either method, I the use the Shop Vac with a 5" disk sander and or trim router for final finish with the same clean results.  However the vacuum hose has some bite marks in it from the router. 

A  strong vac with a clean filter can permit indoor cutting.  Just make sure the hose is right at the point of dust source.  When using a trim router I hover the hose inlet right over the pattern bit.  Over the years the hose may be a inch or two shorter .

I used sound board (similar to homasote)... I did not glue/screw or otherwise attach it to the plywood.  Track and accessory screws are only secured to the sound board (not through to the plywood).  It's dead quiet.  If you run a screw through or glue whatever insulating surface you install to the plywood substrate you will lose a good deal (if not most) of the sound deadening attributes.

I found it a little easier to work with (not much) than homasote.  Here in the south it's primarily made from sugar cane (the leftover waste after processing the sugar).

@Tom Tee posted:

Cutting Homasote, I use a Bosch jig saw, fine metal blades and a Shop Vac with a HEPA filter  holding the hose inlet right at the blade.  When done carefully this can be done anywhere.

The other alternative is to use a Airways # 6 flooring knife available at flooring supply stores and HD.

Couple of passes with a sharp blade and you have a clean dustless edge.

Using either method, I the use the Shop Vac with a 5" disk sander and or trim router for final finish with the same clean results.  However the vacuum hose has some bite marks in it from the router.

A  strong vac with a clean filter can permit indoor cutting.  Just make sure the hose is right at the point of dust source.  When using a trim router I hover the hose inlet right over the pattern bit.  Over the years the hose may be a inch or two shorter .

I have a question regarding Homasote.  I used to be able to get the everyday plain old grey board like what Tom Tee is cutting.  However, now there are a myriad of ‘Homasote’ products to choose from.  Is the 440 SoundBarrier the traditional grey Homasote?

Thanks,

Tom Stoltz

in Maine

You can buy sheets of 440 homasote at Menards.  They carry it in stock.
It is the same as the gray.  I used a router and jig to cut my patterns in homasote  -- which makes a substantially bigger mess than just cutting it with a saw or blade.  If I need more I will hang plastic shower curtains  around my work area and wear a full face mask to cut and clean up.  There is a lot of misinformation about extruded pink or blue foam panels. In free space they don't offer much of a sound barrier.  But using them on top of  a dense surface like plywood does absorb a lot of sound. 

I cut the soundboard outside... and, used a jigsaw with a fine blade (I don't think it was a metal blade but it may have been).   I cut it at about half 1/2 speed and it was 'not' all that messy.   For straight cuts I used a skillsaw with a plywood blade... a little messier than the jigsaw ... but not terrible.

@IRON HORSE posted:

You can buy sheets of 440 homasote at Menards.  They carry it in stock.
It is the same as the gray.  I used a router and jig to cut my patterns in homasote  -- which makes a substantially bigger mess than just cutting it with a saw or blade.  If I need more I will hang plastic shower curtains  around my work area and wear a full face mask to cut and clean up.  There is a lot of misinformation about extruded pink or blue foam panels. In free space they don't offer much of a sound barrier.  But using them on top of  a dense surface like plywood does absorb a lot of sound.

Thank you Iron Horse, Menards isn't in Maine, but others carry the 440 board here.  $30.00 per board now, I haven't bought any in over 20 years.  Cutting Homasote has never been an issue for me, just wanted to make sure I order the correct product.

Tom Stoltz

in Maine

I also use ceiling tiles on top of 1/4” plywood for a Christmas layout. The tiles cost $45.00 for eight 2x4 foot panels. One of the benefits is the white surface makes it easier to simulate snow just add some ground snow. Plus the panels are easier to work with then full sized sheets

@trainbob posted:

I also use ceiling tiles on top of 1/4” plywood for a Christmas layout. The tiles cost $45.00 for eight 2x4 foot panels. One of the benefits is the white surface makes it easier to simulate snow just add some ground snow. Plus the panels are easier to work with then full sized sheets

How is it for walking on while building the layout?

Tom Stoltz

in Maine

Hi Tom

You might consider Fiberboard Roof Insulation.  It is similar to Homasote, comes in 1/2" and 1" thinkness, and 4'x4' or 4'x8' sheets.  It should withstand some foot traffic.  I used 1/2" on top of 1/2" plywood.  It is a lot quieter than a section where I have 1" foam on top of 1/4" plywood.  I only have the track ballasted, no scenery done yet.  Recognize the turnouts?  :-)

The picture shows the "top" side.  The other side has a black finish.

@Tom Tee posted:

Cutting Homasote, I use a Bosch jig saw, fine metal blades and a Shop Vac with a HEPA filter  holding the hose inlet right at the blade.  When done carefully this can be done anywhere.

The other alternative is to use a Airways # 6 flooring knife available at flooring supply stores and HD.

Couple of passes with a sharp blade and you have a clean dustless edge.

Using either method, I the use the Shop Vac with a 5" disk sander and or trim router for final finish with the same clean results.  However the vacuum hose has some bite marks in it from the router.

A  strong vac with a clean filter can permit indoor cutting.  Just make sure the hose is right at the point of dust source.  When using a trim router I hover the hose inlet right over the pattern bit.  Over the years the hose may be a inch or two shorter .

I used the knife Tom Tee suggested cutting Homasote on my current layout build.  It worked pretty slick.  I actually wondered if it would work and at the time didn't know you could get knife blades for jig saws.  By the time I learned about the jig saw blade, I was nearly done with all my Homasote cutting, so just kept using the knife.