Hi, I’m working on planning benchwork for a double deck layout - only problem is that it is going to be attached to the walls and I need to keep the layout rail noise at a minimum. I plan to use 1/2" plywood subroadbed with 1/4" and 1/8" cork on top. I have some homosote (do they really not make it anymore?), but not enough to use under the track - besides, it would be too thick.
I was thinking about using homosote pads between the risers and the subroadbed to dampen the noise. The real problem is the vibrations getting into the walls since the house has almost no soundproofing. Anybody got any ideas? I’m going to use shelf brackets to attach the layout to the walls, and I model in HO scale.
You need to get a copy of the January 2013 MR. In there is an article by Pelle Soeborg called 5 Expert Tip for Installing Track and Roadbed. He discusses sound deadening sub-roadbed. Much easier to read the article than for me to explain here.
Quite frankly, I don’t think that any wheel noise is going to be transmitted through the walls. If it does, than I guess you’re not going to have any sound locos, either. Probably the vibration you mention will be the bigger culprit. But I don’t think that any sort of roadbed will help you there. You might want to investigate installing some sort of rubber isolators between the shelf bracket supports and the walls.
Another option would be to have your lower level supported off the floor, and the upper level brackets attached to some risers that are supported from the bottom level.
If you are contemplating some sound locos I’d set up a temporary shelf, not supported by the wall, and turn up the sound. Blow the whistle and ring the bell. If that annoys your neighbors, you may have to re-think your project.
Hi, I have a similar setup, and have no problem with the sound transmitting thru the walls.
The cork is definitely a help, and for my latest layout I used caulk to affix the roadbed instead of nails - which also should be a help.
One other area that has to have made a difference is my under table supports. The closer you are, the smaller the “drum area” of the plywood. Mine are 18-24 inches, and if nothing else give me a very solid RR.
Sound is most greatly attentuated when it is met by two mediums juzxtaposed that are of varied densities. For example, if you had drywall by itself, it might be quite noisy. If you have wood bound to it and supporting it, it would be much less noisy, place extruded foamboard insulation on the other side of the wood, and the chances are you would hear next to nothing.
If you had a composite roadbed of vinyl underlay, say 1/8" thick, and over top, tightly mated along their lengths with almost no gaps or airspaces, a similar dimension of masonite strips for a top surface, your tracks would be very quiet. I had a trestle made of scale dimensional lumber with Atlas Code 100 caulked to the stringers. Amazingly quiet. The think caulk between two distinct densities, the plastic ties and the stripwood, rendered the sound almost mute.
What makes for noisy trains is the glued ballast. The ballast transmits vibrations and noise through its mass with its essentially homogenous density, and directly to the adjacent sub-roadbed or plywood surface.
One of the best sub-roadbeds for noise, believe it or not, is drywall. I mocked up a temporary track system between layouts using strips of drywall as the surface on which the rails sat. It was deadly quiet.
What you need to accomplish is stop the ‘wheel to rail’ sound from being transmitted to the layout ‘structure’ and then to the walls.
1/2" plywood for subroadbed is good. Just do not lay sheets of the stuff all over(drum head effect). Homasote is messy to cut and the usual 5/8" product is not uniform in thickness. I would buy Homabed from California Roadbed Company. The product is cut to shape and sanded to a uniform .240" thickness. Much easier to work with. Your idea of Homasote ‘pads’ will not fly - Any carpenters glue/screws will transmit the sound through your pad and to the layout structure.
I would attach the Homasote roadbed to the plywood subroadbed with cheap acrylic caulk. And attach the track to the roadbed with the same acrylic caulk. Good sound deadening. Woodland Scenics also has a foam roadbed that can be attached with acrylic caulk - Some folks swear by it, other swear at it.
When you ballast, do not use diluted white glue. It hardens rock solid and will transmit the noise from the track to the plywood. Use something like diluted Matte Medium that remains somewhat ‘soft’ and will not allow the sound to be transmitted. I have heard of white glues that remain somewhat soft, but I have never seen them. Do not use diluted yellow carpenters glue - It will be noisy and be a ‘mess’ before you get done.
I use 1/2" common birch for my subroadbed, with Homabed or cork roadbed attached to the subroadbed with acrylic caulk. My flex track is actually nailed down, and after ballasting with Matte Medium, I pull the nails. The only ‘noise’ I really hear is if the hard shell scenery(plaster wrap) becomes a ‘drum head’. Usually ground cover/trees seems to absorb much of the sound.
Sound deadening has really not been much of an issue until ‘sound’
Put rubber grommets in the screw holes of your brackets. And if you want to get really serious about no noise transmission, use cement board as a sub roadbed and make your roadbed out of topping cement and you will get zero noise transmission. The track here is caulked to the cement.
Dunno where these rumors of them not making Homasote keep coming from. Just because Home Depot doesn;t have 4x8 sheets of something doesn’t mean it’s not being made, despite what some of the so-called ‘experts’ workign there might say.
One definite key in any method actually working is not not have a mechanical connection joining layers. Caulk is great for this, easy to use, easy clean up, and it bonds nearly anything, but not SO strong like other adhesives that you couldn;t remove and reuse track. By not drying rock hard like other adhesives, it provides an additilally layer of different density between the materials, attenuating the sound.
I’m still waiting shipment of a couple of items to have all the options available so I can make a test of 3 different bases with 3 different roadbeds to see which ends up the quietest.
If you are using common shelving brackets to hold a layout to the wall, then you can put a strip of rubber or weather striping between the bracket and the wall. End of that part of the sound problem.
Homasote is a BRAND NAME, and Big Box Stores will not carry it by the brand name, and so their sales boys (er associates) will not know what you are talking about. As for either under-floor insulation material or sound-boards, and they will show you many suitable options. LION likes Celotex the best, but while the Celotex company is alive and well, this particular product disappeared with the advent of fire codes. What you want are light weight (Homasote is rather heavy) sheets that are dimensionally stable, easy to cut yet durable. Do not ask for Homasote, tell them you are building a train table and describe what you want: A sheet of soft, stable material. Or else just go to the Homasote website and find a dealer near you.
Noise? What is the problem with noise. LIONS like noise. Listen to the LION ROAR:
They most certainly do. For a wide variety of reasons, I was in three Home Depots and two Lowe’s this past weekend. All five stores stocked it and it was explicitly labeled Homasote in all of them.
Wow! So much good advice mixed in with worthless Old Wive’s Tales that the poor OP won’t know what advice to take. As an acoustical engineer having spent several days recently actually measuring the vibrations from the BNSF main line through Anaheim/Placentia, I can help a little here.
There are few effective means of mitigating vibration transfer other than high mass and resilient isolation of the vibration source from the high mass. Starting at the vibration source (the model train), there is no significant way to reduce vibration transfer between the train wheels and the track rails other than to make sure the track is as smooth as possible. The first opportunity to isolate the vibration source from the high mass of the benchwork is to use a non-hardening caulk or glue to adhere the track to the roadbed. By non-hardening, I mean a caulk or glue that stays soft and pliable after it has cured. Something that stays as soft as silicone gasket sealant for automotive use would be best. Besides a non-hardening caulk or glue, there should be no other physical and/or mechanical connection between the track and the roadbed/subroadbed. Even the wire used to operate the points of a turnout could be a vibration path into the layout benchwork if care is not taken to isolate the swith motor from the bechwork.
Yes, it is true that ballasting the track can negate any vibration isolation you achieved with your non-hardening track/roadbed adhesive and massive or resilient roadbed material. Using a ballast cement that remains more flexible than white glue can help but a better approach is to ensure that your ballast/glue mixture never touches the subroadbed. When ballasting your track, place a few layers of waxed paper (or other non-stick material) along the edges of the roadbed. A slight overlap of the roadbed edge is desirable. Now apply your ballast and glue mix. Once the ballast and glue mix has cured, carefully pu
Thanks for all the help, but there are a couple things that might affect the sound deadening solution.
I have a few sound-equipped locomotives and hope to have the rest of my locos equipped with sound in the next year or two. The layout is going to be partially built off the wall and partially supported by a box of 2x4s in the middle of the peninsula. The layout also must be able to be disassembled in sections that are no bigger than about 30" by 5’. I plan to do what was done on the Mississippi Alabama and Gulf (see the latest issue of GMR) and use 1x2 or 1x3 open grid modules over 1x3 stringers atop the brackets. I also plan to have a train elevator (not powered) along the back side of the peninsula.
Naturally using concrete for the roadbed won’t work because of weight, but it’s interesting because the extreme mass must dampen vibrations.
Rubber isolators between the shelf and wall are a possibility, but the screw into the wall could transmit the vibrations as well as the shelf bracket. If I do put rubber there, then the shelf and backdrop would have to have rubber behind them as well.
What I meant by using homosote insulators was that the roadbed would be nailed/screwed to one part of the homosote, and the rider would be nailed/screwed to another part. Thinking about it now, I believe that it would be easier to just make the risers out of 1/2" homosote with risers every 16" or so. The roadbed is going to be 1/2" ply as I said. That, cork roadbed, and matte medium holding the ballast should dampen any vibrations.
Any thoughts now that I’ve clarified a few points?
Thanks for this information. I’ll definitely try the matte medium when ballasting and also to vary densities of supporting & mounting materials. Drywall. Hmmm. I usually try to avoid it. But thanks for these tips. I read of people using foam “camper tape” & cork combos-and the matte medium for ballast came up too for reasons you describe. I wonder about the life of foam tape, whether it will crumble and decline over the years. Cheers, G
Did you ballast after? I’m wondering if the drenching with “wet water” (water and detergent or water & alcohol) and diluted matte medium would make the dry wall swell and be uneven, giving the track waves we do not want.
A few years ago I read an article on hand laying track. The author suggested using latex paint as the glue for the ties and/or the road bed. He also said this would act like a sound reducer. With all the talk of latex glue, he might be right. I did a test on a piece of plywood to see if the paint worked as glue. It does and the ties are permanently attached to the plywood. As for sound reduction, I don’t know.
There are some advantages to using latex paint. It’s cheaper than matte medium and caulk. It’s really cheap if you find the color you want in the reject bin of the paint mixer. I have a gallon of flat light brown ( dried dirt color ) latex paint that has to be 15 years old. I use it as the base paint of my scenery and roadbed. In the next few months I am planning on installing about 80’ of hand laid track directly to a 5/8" thick plywood base. I am thinking of using latex paint as the glue as I have to paint the plywood anyway. I usually use white glue on cork. It will be an interesting experiment.
One roadbed material I haven’t seen mentioned is foam pipe insulation. It is 2" wide and 1/8" thick and has glue on one side. Here is one example from Lowes.
This one says foil and foam. The type I have used is plain black foam with glue on one side.
A lot of people look to the roadbed. But i also find gaps in the track to be noisy. Also having well running wheel journals (oil/greese in very light quantities) helps.
Hard ballast does conduct vibrations which can generate sound. But its irregular surface serves to diffuse sound coming the train itself. (There’s a difference between reflected (Sound absorbtion and reflection) and transmitted sound (STC/SRI)…each has a unit of measure #)
As someone who built home theaters and studied it extensively (coupling damping transmission and reflection) you would best consult the home theater build thread at avsforums.
I can also recommend green goo between the roadbed and sub roadbed as a starting point along with minimizing gaps and keeping your journals smooth running
I’m not an expert in it like some. But I did build 5/8" Drywall with green goo and 1/2" dry wall on top of that. These are decoupled walls using RSIC clips on staggered stud 2x4’s on 2x6 plates. And the results are quite impressive.
And my subwoofers sit on a sand pile (mass damping) and the flooring or rubber feet. Even my door has rubber seals to keep sound from escaping.
But thanks for these tips. I read of people using foam “camper tape” & cork combos-and the matte medium for ballast came up too for reasons you describe. I wonder about the life of foam tape, whether it will crumble and decline over the years. Cheers, G