Question on roadbeds and ballast

Model Railroader Layouts and layout building
1

Just finished watching part of a video sent to me by MR. It has the table surface made from birch plywood topped with construction foam sheets. That being the case, I have some questions:

  1. One of the stated purposes of the cork roadbed is “quiet operation”. But do you use it on top of the foam as well? Is this overkill?

  2. Is there a covering (material, paint,etc.) of any kind put on top of the foam sheets first?

  3. If you do, in fact, use the cork roadbed, I would assume that it is glued in place on the foam. So, what type of glue is best?

  4. If I’m going to go as stated above, then how is the track itself attached? More glue? Nails or brads? I am thinking that any type of nail or brad is now going only into cork and/or foam (as opposed to into the plywood). Is that enough to hold it?

  5. Finally, I’d appreciate all suggestions on ballast. Material to use, method of application, etc. This is something I have never done.

Thanks everyone!

2

When I built my last layout I used “Latex caulk” to glue the foam board down to the plywood and craft matte medium to glue the cork roadbed and track down to the foam. I tried using white glue and found that it dried to hard and transmitted sound too good. It made the plywood and foam board act like a drumhead. As for ballasting I had to move and dismantled my layout before I got that far. But I will say that the matte medium did make taking up the track easier then the latex caulking did on the foam board. I used too much caulking. When I laid the cork and track I used “T” pins to hold it in place while the matte medium dried then removed the pins once dried.

3

My layout uses 2-inch construction foam on a wood frame benchwork. There is no plywood layer, nor do I think one is necessary. The foam itself is very stiff. Foam will not support people climbing on top of it, however, so if you must do that during construction, then plywood might be a good idea. Once you have foam on top of the plywood, however, don’t climb on that. Your weight (well, my weight, anyway) would easily crush the foam.

I used latex caulk to attach the foam to the benchwork. After 3 years, no problems.

I use Woodland Scenics foam roadbed, too. This is a different material than cork roadbed. Most of my roadbed is held on with latex caulk, although I’ve put some down with white glue. I don’t think I can tell the difference in sound level. The foam roadbed is softer, though, and probably is better at reducing noise than cork.

The real purpose of roadbed is to elevate the track above grade level in a prototypical fashion. It isn’t there for cushioning or noise reduction. It’s a scenic thing. Many modellers use no roadbed in yards or on industrial sidings, for example, and they instead just lay the track directly on their base foam or plywood. (Yes, they do need a short “ramp” section to change elevation a bit.) Again, that’s the way the real railroads do it.

I glue my track down, too. Once again, I’ve mostly used latex caulk for that, and sometimes I use white glue. Both seem to work about the same. Latex caulk, by the way, comes in a tube and is applied with a caulking gun. The only problem I have with the stuff is shelf life. Once I open a tube, it starts to harden, even in the tube, and after a couple of months the tube is ready for the trash. When you’re starting out and building benchwork, gluing on foam and laying lots of track, that’s not much of a pro

4

If you use cork, remember to round off the top outer edges of the cork before you lay your track. Very important! I don’t know whether the foam is rounded off or whether you have to do that. I used Woodland Scenic’s Hob-e-Tac cement to stick the gravel to the outer bank and the rounded off corner at the top of the cork. For the ballast between the rails and ties, I diluted white glue about 7 parts water to one part glue. I poured the gravel between the rails and used a long, soft bristled brush which had almost no spring to brush the ballast between the ties. This brush is just the opposite of what Dave Frary advises in his books but it was the only way I could get the individual “rocks” off the top of the ties. I then took my water and glue mixture and used an eye dropper to put a drop between ties. You could see the capillary action spread the glue to the extremities of the box created by rails and ties. This is again just the opposite of Frary’s method. I tried his and sprayed the track. When the water mist hit the ballast, it caused it to bunch up rather than lie flat. I then poured my ballast onto the ties outside the rails and worked it with the brush until it reached the ballast previously tacked to the beveled edge of the cork. I used the eyedropper method to attach this ballast, too. My method, admittedly, takes a while and I haven’t done the whole layout yet but it is a most relaxing part of the process because there is no guesswork to whether you are doing it right and it doesn’t have to be done before something hardens. The ballast stays down unless I touch it with a finger. Any such pressure will break the glue bond. But we don’t usually stick our fingers on the track so that has been of no concern. One other thing. I’ve noticed that nearly everyone tends to take methods and change them slightly to fit their needs. And it works! The nice thing about model railroads is that in most cases, the track, trains, buildings and scenery come together to perform magic and, like the vel

5

Like Mr. Beasely, my HO-scale Yuba River Sub garage layout is built with 2" extruded foam on a wood frame construction. Everything he says about the foam is true, however I cross-braced under the foam about every 12" to ensure stability. My roadbed is WS foam on WS risers for my grades, and I laid everything down with latex caulk and in some portions, Elmer’s Carpenter Glue (only because I’d run out of caulk and I was in a hurry, LOL!). Both have worked for me very well so far in the 7-plus life of the railroad.

For the most part my trackage is laid down with latex caulk, and I used long WS scenery pins to hold the track to the proper radius while the caulk dried. I do have one portion of the layout–Yuba Pass–where instead of using flex-track, I used EZ wide radius (34") track to ensure very even radii on curves on trackage that overlook a sheer six actual foot drop to the concrete garage floor. The EZ track affixed to the WS roadbed very easily by using a bead of caulk along each side of the EZ track roadbed.

For ballast, I’ve used a mixture of medium and fine WS ballast in various shades to represent both main and yard trackage, and I’ve used the old method of thinned white glue and ‘wet’ water (two drops of liquid detergent in a spray-bottle of tap water), and it’s worked fine for me. Remember to go over the inside of the rails lightly with a small screwdriver after the ballast dries to get any specks off that might hinder your running, and vacuum up the residue.

I like the foam base, it’s lightweight and very sturdy. And it does tend to cut down the ‘rumbling’ noise of the trains running to a degree. Of course, I don’t mind the ‘rumbling’ very much, anyway. Ever stand next to a real train running down a heavily ballasted mainline? Now THERE’S some ‘rumbling’ for you.[:P]

Tom [:)]

6

[quote user=“jockellis”]
If you use cork, remember to round off the top outer edges of the cork before you lay your track. Very important! I don’t know whether the foam is rounded off or whether you have to do that. I used Woodland Scenic’s Hob-e-Tac cement to stick the gravel to the outer bank and the rounded off corner at the top of the cork. For the ballast between the rails and ties, I diluted white glue about 7 parts water to one part glue. I poured the gravel between the rails and used a long, soft bristled brush which had almost no spring to brush the ballast between the ties. This brush is just the opposite of what Dave Frary advises in his books but it was the only way I could get the individual “rocks” off the top of the ties. I then took my water and glue mixture and used an eye dropper to put a drop between ties. You could see the capillary action spread the glue to the extremities of the box created by rails and ties. This is again just the opposite of Frary’s method. I tried his and sprayed the track. When the water mist hit the ballast, it caused it to bunch up rather than lie flat. I then poured my ballast onto the ties outside the rails and worked it with the brush until it reached the ballast previously tacked to the beveled edge of the cork. I used the eyedropper method to attach this ballast, too. My method, admittedly, takes a while and I haven’t done the whole layout yet but it is a most relaxing part of the process because there is no guesswork to whether you are doing it right and it doesn’t have to be done before something hardens. The ballast stays down unless I touch it with a finger. Any such pressure will break the glue bond. But we don’t usually stick our fingers on the track so that has been of no concern. One other thing. I’ve noticed that nearly everyone tends to take methods and change them slightly to fit their needs. And it works! The nice thing about model railroads is that in most cases, the track, trains, buildings and scenery come together to perform magic

7

I gave up trying to make roadbed quiet about 20 years ago. It’s all crap, the train will make noise no matter what you do so why knock yourself out by trying to square the circle? As was stated before, real trains make noise, and lots of it, so get yourself an inexpensive sound system and listen to that, not your roadbed. The closest thing I’ve ever experienced to a “quiet” train was on the AMTRAK electric lines up north- but even those make sound (and sound very similar to a model train running on noisy roadbed).

8

Overkill ? No; but you won’t find a more cost-effective, easy-to-use, easy-to-find product to create the profile of a roadbed.

NOTE : If you do use foam sheets, be sure it is the extruded foam (pink or blue) and not the expanded foam (white). You’ll find the extruded foam far easier and less messy to work with than expanded foam.

You can use latex paint. In fact, most people paint the foam a brown-ish colour before laying any track. This provides for a good base-colour for whatever ground cover you plan to use.

Since foam won’t hold nails, you have to use an adhesive. An inexpensive easy-to-apply adhesive that many people have had success with is latex caulk. Spread a very thin layer along the path your tracks will take, place the roadbed, then use long sewing pins and weights (eg: canned vegetables) to hold the roadbed in place as the caulk sets (at least overnight). Latex caulk comes in many colours. I would suggest using clear (goes on white and dries clear). Be sure to use a paintable caulk so that you can paint over any that might squish out from under the roadbed.

[quote]
4. If I’m going to go as stated above,

9

I’ve used the Woodland Scenics foam roadbed, atop extruded foam sheets, on a friend’s layout, and we used WS cement to fasten it in place. We then used regular Atlas track nails to hold the flex track in place, which seems sufficient for now. Ballasting should provide a more solid method, when we get around to it. One of the drawbacks of the foam roadbed is that it’s difficult to transition down to yard areas, or, as on his layout, to the turntable, which was already in place. We ended up using a length of cork roadbed there, which was easy to sand down to make a gradual slope.

On my own layout, I didn’t use foam, as mine is 3/4" plywood roadbed atop open grid benchwork. The flex track is on cork roadbed in most places, or directly on the plywood, and held in place with Atlas track nails. I ballasted the track using the following method, which is cheap, easy, and effective. After ballasting, the track nails can be removed, although I didn’t bother.

To ballast your track, I find that a small paper cup (such as those kitchen or bathroom Dixie cups) gives you great control over where the ballast goes. I usually move the cup along the centre of the track, tapping it as I go, to keep the ballast flowing. Less than you need is better than too much, although a soft 1/2" brush is useful for pushing around the excess or levelling what’s in place. Then go back and do both roadbed shoulders in turn. Use the brush to level and re-arrange things as required, making sure to keep the ballast away from the throwbar area and the flangeways of the guardrails. To remove stray ballast from the tie tops, lightly grasp the metal ferrule of the brush between the thumb and forefingers of one hand, laying the handle across the rail tops, then, as you move the brush along the tracks, lightly and rapidly tap the brush handle with the fingers of your free hand. The stray ballast will “magically” bounce off the ties and into place between them.
If you’re also ballasting turn

10

I used EZ-Track caulked directly to 1/5" extruded Dow foam on my first layout. It was noisy after I ballasted the plastic ballast base that comes on the EZ-Track. Currently, I use both cork and vinyl underlay as roadbed, and they are both very quiet. Out on my mains, I usee spline roadbed, and merely used caulk to adhere the flex track sections to the splines. They are dead quiet.

The secret to quiet tracks, in my opinion, is to use at least two different layers of material of different densities. I learned this in my other hobby, Astronomy, when trying to dampen out vibrations in my telescope. After touching the scope for any reason, it would vibrate, osscilate really, for several long seconds as viewed in the eyepiece…whatever I was viewing would wave back and forth for up to 6 or seven seconds. Using specially designed foot pads to keep the tripod off the ground or a deck made a huge difference. So, too, with a thin layer of caulk and cork or MDF or vinyl between your main bench and the ties. Dual densities do the magic on my layout, and it is gratifyingly quiet.

11

Jay, Why would you stick your finger into the ballast after you’ve put it down. I asked because my ballast stayed perfectly for over three years until a couple of weeks ago when I stuck my finger between the ties and, by golly, you’re right. It did come up. But the stupidity was my sticking my finger on the track. Reminds me of the days when Minolta sold the SRT 101. Everyone I knew that had one had to take it to the repair shop because they had stuck their fingers in the shutter while it was on bulb then let it close on their fingers. Of course it broke. But the problem was with the photographer, not the camera. My conclusion was that stupid people bought Minoltas. I must be stupid for having stuck my finger into the ballast, too!

12

I am a “hardshell” man so I can’t address the issue of foam.

I “overkill” with a sandwich of 3/8" plywood, 1/2" Homasote®, and cork roadbed. On my last layout I tried laying some of my ballast using water based glue on the off chance that it might allow me to salvage my flex track when and if I decided to/had to discard it. I did the latter a year ago; I was able to recover my flex track but it was a chore. I had not tried it with my handlaid switches but now that I know it will work I should be able to recover my frogs on any future layouts.

13

You asked about what material to use for ballast–ground walnut shells. Years ago , I stumbled onto the ‘home’ of a rather well known southern calif company who blends and markets the ballast. I had always envisioned this large factory setting, but in fact, it was set up in a shack in their back yard.

They had 2 or 3 small (3 cubic foot) concrete mixers and would put the ground shells into the mixer and dribble latex house paint into the shells as it turned. I believe that they just let it turn until the mix was dry. I was able to acquire aboout a gallon of over spill from the floor and still have most of it, although its a pain to sift out the debris.

Where to get the shells? One of the uses is for tumbling cartridge cases to clean them before reloading. Most gunshops who have a decent reloading section should have it, but it may be a little course for your scale. I got lucky at the last gunshow and got a gallon of ultra, ultra fine for about $4.00. You could also try a sandblasting shop–if they still use it what with all the new technology.

If anybody is interested, I’m going to the show over Thanksgiving weekend and should be able to buy more or get the name of the source(somewhere in Iowa). Next trick is what to use for a mixer??–Steve

14

Using the methods which I described above, you should be able to use a shop vac to vacuum the track, and not be concerned about lifting the ballast. Incidently, if you accidently spill too much ballast (or ground foam) while doing scenery work, you can easily recover it by using a shop vac or any vacuum with a hose attachment: simply remove the nozzle or tool attachment on the end, cover the rear opening of it with a piece of old pantyhose or nylon stocking, the re-attach it to the hose and vacuum. The nylon will prevent the material from being drawn into the cannister, and it can be dumped onto a sheet of newspaper, then returned to the original container, for re-use.

Wayne