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.
Thanks
Modeling the Pennsy and loving it!
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.
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
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.
Crandell
What you need to accomplish is stop the 'wheel to rail' sound from being transmitted to the layout 'structure' and then to the walls.
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' engines started getting popular. Our club has 2-4" of foam over 1/4" plywood. Cork roadbed is attached with contact cement as is the flex track. There is significant 'noise' when 7-8 long trains are running!
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
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.
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Brent
"All of the world's problems are the result of the difference between how we think and how the world works."
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.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
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:
wtxsdwqv08
The Route of the Broadway Lion The Largest Subway Layout in North Dakota.
Here there be cats. LIONS with CAMERAS
I use the method that Jim described and I don't have any problems. I also run ALL sound locomotives, and metal wheels in my rolling stock.
Elmer.
The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.
(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.
BroadwayLion Homasote is a BRAND NAME, and Big Box Stores will not carry it by the brand name
Homasote is a BRAND NAME, and Big Box Stores will not carry it by the brand name
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 pull out the waxed paper. This will maintain a slight gap between the ballast/glue mix and the subroadbed eliminating any chance of the ballast transferring noise and vibration into the subroadbed.
The first opportunity for high mass is the roadbed. Using dense materials such as drywall and cement products might seem like a bit of overkill but they will definitely work as acoustic mass. However, the subroadbed can also be used as an additional layer of isolation should you not want to work with less conventional materials. Cork roadbed will work as an isolator but the Woodland Scenics foam roadbed is an even better isolator. Whatever roadbed material you choose, use only a non-hardening caulk or glue to adhere it to the subroadbed. Again, there should be no mechanical connections between the roadbed and the subroadbed other than the non-hardening caulk or glue. If a rigid roadbed material is used (drywall, wood, homasote, etc.) care should be taken to ensure that the non-hardening glue completely separates the roadbed from the subroadbed. Use some kind of thin shims or spacers to maintain a physical separation during the gluing process.
The next opportunity for high mass is the subroadbed. Half inch or thicker plywood is a good choice although there are more massive building materials. 5/8" thick drywall and 1/2" or thicker MDF are both heavy materials that make good acoustical mass. Although certainly not as strong as similar thickness plywood, drywall and MDF will work if well supported. Other non-conventional materials such as cement board would also work but the skills needed to work with these materials could cause some modelers problems. Using a non-hardening caulk or glue to adhere the subroadbed to the benchwork offers yet another layer of isolation between masses. Just be sure that all nails and/or screws used to temporarily hold the subroadbed to the benchwork are removed after the caulk or glue has cured. Any nails or screws left behind become direct vibration paths into the benchwork. Again use thin shims or spacers to maintain a physical separation until the caulk or glue has cured.
Successful isolation of any benchwork attached to the walls of the room can be difficult. As previously suggested, the best approach is to design the benchwork to be supported only from the floor with no connections or bracing of any kind attached to the walls. Attempts to isolate building framing by sandwiching rubber between two pieces of wood is common but the nails or screws holding the sandwich together create direct vibration paths between the framing members. True vibration isolation mounts are expensive and most modelers could not justify such expense. Rubber grommets, though a little better than the rubber sanwich, do not constitute true vibration isolation mounts mainly because they tend to get compressed too much in the desire to make the assembly stop moving around.
If the benchwork must be attached to the wall studs, you can increase the noise and vibration resistance of the wall. However, you need to throw out a lot of Old Wive's Tales to do it correctly. If your walls are lath and plaster, leave them alone. Any attempt to improve their noise and vibration resistance will likely make things worse. If your walls have drywall, all mitigation should be done from the side of the wall opposite the train room. Start by first removing the drywall from the side of the wall opposite the train room. With the lights on in the train room and the lights off in the room your working in, look for light leaks through the trainroom side of the wall. Fill all such leaks with caulking including those around the backside of any electrical outlets. If the outlets are really bad, apply Lowry #10 putty pads or red fire pads tightly around the outlet boxes until no light leaks show. Now insulate the stud cavities with R-13 fiberglass open batt insulation. Do not pack any additional insulation into the stud cavities. Do not use spray on or expanding foam insulations, and do not use any rigid form of insulation. Forget about "Soundboard" as it simply doesn't work. Increased insulation "R" values do not translate into increased noise reduction. Thermal and "acoustical" insulations are piss poor sound barriers no matter how you slice them. Adding some helps a little but adding more does NOTHING! Put your money elsewhere.
Now, pull any electrical outlets in the modified side of the wall forward and remount to match the new wall face (about 1 3/4" further forward) Now apply single leg resilient channels perpendicular to the studs at 16" on center with the stud side flange pointing toward the floor and the drywall side flange pointing toward the ceiling. Attach a new layer of 5/8" Type "X" drywall to the resilient channels (and only to the resilient channels) using screws no more than 1" in length. Be careful that no drywall screws make contact with the wood studs. Leave a 1/4" gap between the new drywall and the ceiling, side walls and floor. Now thoroughly caulk all seams between the drywall panels and fill the perimeter gap with a non-hardening caulk. Now attach a second layer of 5/8" drywall to the resilient channels (and only to the resilient channels) using screws no more than 1 5/8" long. Again, be careful that no drywall screws make contact with the wood studs. Stagger the drywall panels so that you don't have second layer seams directly atop first layer drywall seams. Leave a 1/4" gap around the perimeter of the second drywall layer. Fill the perimeter gap and any gaps around the relocated outlet boxrs with non-hardening caulking. Finish the drywall and paint. From this point on, never hang anything on this wall heavy enough to require attaching directly to the studs. Hang it somewhere else.
The above wall modifications will yield a good 10 dBA of additional noise reduction with similar vibration reductions if done exactly as described. Do not shortcut the system by sandwiching the resilient channels between the existing and new drywall layers. It doesn't work and I have the test results to prove it.
Hope these suggestions help.
Hornblower
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?
Schuylkill and Susquehanna 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?
Sounds like a good combination of noise limiting methods. Let us know how happy you are with the results. Cheers, G
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.
South Penn
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.
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
What is "green goo"?
Jay
C-415 Build: https://imageshack.com/a/tShC/1
Other builds: https://imageshack.com/my/albums
An article by Pelle Soeborg got me thinking about when I used to install furnaces and A/C during college, and the tape we used to seal ducting. I'm considering using this product. Two strips side-by-side will be the same width and thickness as cork roadbed, will help navigate curves like cork roadbed, is self-adhesive (sticks like heck), and seems to round off at the edges. $9 for 25' - not too bad, and cheaper than cork at many outlets.http://www.bestmaterials.com/detail.aspx?ID=9591Whatcha think guys?
Have fun!
Dan
That was actually once sold as roadbed. It's ALMOST sticky enough to hold the track with no adhesive or nails. AMI Instant Roadbed. Some people liked it. A friend of mine used it on part of his N scale layout, over time the track let go. It's still solidly stuck to the plywood though. I would not trust it to be self-adhesive, but it should be a decent option.
I will not dispute the detailed technical advice regarding various methods of sound control outlined above, but I will suggest a much simpler approach that I have found to produce quiet results, results that are more than "good enough."
My benchwork is open grid framing covered by 1/2" plywood screwed not glued) to the framing. 1/2" Homasote sheet is fastened by screws (not glued) to the plywood. This Homasote sheet-though not perfectly uniform in thickness-is uniform enough with the provision of a very few track shims at low spots and minimum sanding at high spots (primarily at joints). This sheet is the "roadbed" to which spurs and sidings are attached.
Actual roadbed is Homabed attached to the Homasote sheet with brads (not glued).
Track is Walthers/Shinohara Code 83 spiked (not nailed or glued) to the Homabed and Homasote.
I have not yet ballasted the track, so its affect on the assembly is yet to be heard, but trains running on the above-described assembly are very quiet, generating only wheel noise and clickety-clacking over the joints.
Dante
IMO, most of the noise comes from ballasting the track, which effectively allows the vibration to bypass much of the preventative measures used when installing the roadbed and the track.
I have read different modelers trying different combinations, but I have not yet heard of anyone trying something that Hornblower mentioned above....
Isolating the ballast from the subroadbed by using waxed paper on the subroadbed to create a small gap,then removing the paper after the ballast has hardened.
A lot of modelers mention how the noise increases after they ballast, so experimenting with this installation technique might be educational.
- Douglas
I was making some up grades to a setion of track that was not ballasted. About 2' away was a section of track that was ballasted. When I was finished I pushed , by hand, two passenger cars to check the track work. When the cars rolled onto the ballasted section, the noise increased by at least 50%. I never noticed this noise before.
The ballasted track was done years ago using diluted white glue on cork roadbed. The roadbed was nailed to 3/4" plywood.
I'm not going to rip out the track that is ballasted, but I will rethink how I do the next section of track.
Matt medium is the way to go, on a 4 to one ratio, you get alot. I can buy matt medium at Michael's for $12 for 16oz or equal to 4 bottles of thw Woodland Scenics stuff, enough to do my entire 15x30 layout almost (I have a rather large yard that is covered in ballast).
What matte medium are you buying from Michael's? When I do a search for it on Michael's site the only clear matte medium that comes up is Modge Podge.
I've been using caulk to glue cork roadbed on 1/2" ply, then paint/seal the roadbed with enamel wall paint, then glue the track onto the roadbed with the caulk, then Scenic Express natural stone ballast with diluted white glue.
I get very little noise with the track just sitting on painted roadbed (stuck on with double sided tape or nailed down in spots). The noise is much louder when the track is caulked down, and noisier yet when ballasted. Diesels are still pretty quiet but wheel noise from steamers is very noticable. Double-heading two Spectrum 2-4-0's is the worst even with the speed tables carefully set.
I just laid some new track on cork roadbed using push pins through some of the spike holes, then cut the pins flush with the ties. I am thinking of skipping the caulk and ballasting the track as-is. Does flex track have to be firmly spiked down or glued down before ballasting? I don't want any trouble down the road but thinking skipping this might reduce the noise.
Huntington Junction - Freelance based on the B&O and C&O in coal country before the merger... doing it my way. Now working on phase 3. - Walt
For photos and more: http://www.wkhobbies.com/model-railroad/
Michael's sells Liquatex (a known brand) in two sizes, 8 & 16oz in store and I use a 50% off coupon. Part of the proublem is using plywood. I use foam and it transmits sound much less but to realy get rid of the sound you need to eleminate the drum, haven't gotten to that part on my layout as the skirting will eliminate a lot of it. I experimented with covering the bottom of a module and 1/2 the sound seemed to go away (and I wasn't very carefull with doing the mockup). Was thinking of getting a sound meter, they are cheap, but I get tired of having to reinvent the wheel, too many people are tied for some reason to the way something was done, to do new and better ideas. They said not to use beaded foam, I tested it and looked up date on a fire ferensic web site and found that the way we use it, that was hogwash, I find a lot of this stuff, as my daughter says, the internet is our friend!
Liquatex is available from Amazon.