I am currently building a new layout (my second) and have been reading on this forum about using insulation foam for a base and gluing the track directly to the foam using latex caulk. I had not heard of this method until recently and have decided to try it, so i have a few questions.
Firstly, how much caulk would have to be applied to the base of the track, i.e. smeared all over, or a few select blobs?
Also, how would flexi-track be glued in place without it moving?
I do have a few ideas about these potential problems, but I thought I would ask first it, may save me some bother.[:D]
Many of us use acrylic caulk to glue down the track. I glue cork roadbed to the foam base and then glue the track to the roadbed. Apply a bead along the roadbed and smooth it out with a putty knife (if you use blobs the glue will rise up between the ties and make a mess as well as making neat ballasting impossible). Flex-track will hold fine depending on the curve radiius (large radiiuses works good) - you may have to nail down the track on some curves until the caulk dries. The caulk dries fairly quickly and will hold the track firm, but will still let you adjust and align; press down firmly when you’re satisfied. Use the type that dries clear.
You will get a lot of help on this one. Good luck.
Ron K.
The idea is to smear a thin layer of spread out caulk on the foam along the centerline of the track to glue it down. A few blobs here and there would not hold well enough. As for flextrack, use your favorite pin (T-pins, push pins, etc) to hold it in place while the caulk dries. After that you should be able to remove the pins and have the track stay in place.
Buy some PUSH PINS at Stapels or Office depot, the kind you use on a cork board. If you get them in colors you can color code where you want items on the siode of the cork. We use Yelloe to show where their are gaps and Red and Black on the side to keep the A&B rail straight.
Take Care
I’ve started using this method myself, and think it’s great. My few thoughts on it:
Buy the cheapest caulk you can find, that’s the stuff you want. Acrylic latex caulk. No silicone additives, no “paintable” caulk, definitely el-cheapo
You need a much thinner layer than you may think. I lay down a thinnish bead on the centerline and spread it with a putty knife. The caulk I use is white, and if I can’t see the centerline through the caulk, it’s too thick. I started off using too much, and over time found that you literally just need a paper-thin layer.
My track is layed on cork roadbed over 2" foam, so I use T-pins to hold it down. I’ve found this necessary only on curves 24" radius and below. My 30" radius curves (all mainline, most of my layout) seem to hold fine without pins.
I use the same method as mentioned above but have used heavy objects to hold the track in place. What’s really nice about using caulk: It’s easy to pull the track or cork roadbed up to make changes with out damaging them. (after the caulk has died)
A bit off topic, but I have learned to check the levelness of the track all along its length, but particularly at joins. We handle the joins five times as much as anywhere else, and tend to press down as we get them snugged up…bad news on a curve that an articulated loco has to negotiate, especially near 18-24" radius. Even if you are not running large steamers, your diesels and cars will wobble at turnouts and at joins if you do not take care to use a long level or something and check for daylight under its length when you lay it on the tracks. I added this comment because weighting the track brings risks of uneven track if your weights are not consistent from place-to-place, of if your subroadbed is inconsistent. By all means, use weights to hold the track until the caulk dries, but be prepared to adjust it when you check it for level. And do check it.
I’m in “ain’t broke, don’t fix it” mode on this. Putty knife works great for me, and I actually like having the “can I see the line or not” test to determine if I’m laying down too much caulk. Any adhesive spreader I’ve ever seen (even the smallest notch) would lay down more caulk than I want.
I use Atlas flextrack - code 100 and 83 for most of my track (100 for hidden track - it’s cheaper, and 83 for mainline tracks. Sidings, yards and spurs are code 70). I caulked one of my staging yards down last year, but everything laid before that had been laid using track nails. All my track is on cork on plywood (except for some I laid several years ago, which is on homasote).
I was amazed at how much running noise I get from the caulked track! The nailed track is nearly silent in comparison.
Caulking was much faster than nailing,but I’ll nail all remaining hidden track, and only glue down visible track (I figure the ballast glue will made the visible track noisy anyway, so why not glue?
This is totally contrary to both my experience and any common sense. The nails provide a solid conductor of sound and vibration from the track to the plywood, while the caulk provides a different density layer betwen the track and the wood which prevents sound transmission. Did you use latex caulk, or Liquid Nails? Liquid Nails dries hard as a rock and will make more noise.
Use liquid nails and you’ll have to destroy the rails and everything around them if you want to make a change. Like you said, it dries hard as a rock. What you want is something with some flex to it. Caulk allows you to just slip a putty knife under the track and gently pry up and the whole thing comes up in one, reusable piece.
I’m not sure if it’s the deciding factor anyway. On my layout, I have track on plywood, some caulked, some spiked. I have track on foam, some caulked direct, some spiked to the foam with long pins (no caulk), some caulked on top of cork roadbed, itself caulked to the foam.
By far the noisiest sections are those directly on the foam - and caulked or pinned makes no difference. The quietest sections are those caulked on cork on foam. The plywood-based is in between, and caulked or spiked seems to make no difference.
None of it is yet ballasted, and I’m curious to see how ballasting affects this (I play to use Matte Medium rather than white glue, to try and minimize sound)
I don’t install the track nails tight against the ties - I leave a very small gap (a few thousandths of an inch) between the bottom of the head and the top of the tie so that the ties doesn’t bow up on the ends and narrow the track gauge. W-A-Y back when I was learning to lay flex track this was the method described in Model Railroader magazine. I’ve never varied from it until trying the caulk.
The caulk may not be a particularly good sound transmitter because of its flexibility, but the slightly loose nails allow the track to float, and are small discreet points of connection between the plywood and the track, wheras the caulk is continuous.
In any case, whether it makes sense or not, that’s what happens. The nailed track on the same sheet of plywood, on the same sheet of cork, is much quieter than the caulked sections of track.
In fact, I’m going to caulk a short section of track in my helix halfway up (or down, depending on which way the train is headed), because I’ll be able to tell by the suddenly-louder sound of the train when it’s halfway through!
I’m just finishing my third layout and I did it differently this time around. I used the black Woodland Scenics foam road bed over 1 1/2 inches of Dow extruded foam insulation board. I glued the road bed to the insulation board with Liquid Nails foam glue in the caulk gun tube. I tried using the same glue for the track, spreading it thin, then placing the track down, but it made too big a mess.
Now I just use a thin layer of white glue spread on the track bed with a brush. Then I hold the track in place with some long finishing nails pushed down into the foam insulation until the glue dries. I sometimes put a book or other weight to hold the track in place until it dries.
I’ve had no problems with the track popping up unexpectedly and the layers of foam make the trains surprisingly quite. Some of my newer locomotives make almost no sound at all.
I just completed my first Fast tracks #8 turnout, and mounted it on 5/8" plywood. I used leftover strips of gyproc (drywall) for subroadbed, overlaid them with the usual cork, and then used drywall screws to snug up the flextrack (code 100) and turnout through the ties,cork, and drywall…no glues. I used a screw every 6" or so.
Is it ever quiet!. Now, if I could figure out how to replace the screws…maybe careful ballasting and painting.
I do pretty much the same thing as everyone else except I use silicone latex caulk. It comes out white and dries clear. A little goes a long way. There’s one thing I do different and that is to use clamps instead of pins. I have 1/4 inch pieces of plywood in different lengths, up to 8’ long that I use to get a extremely tight bond. I’m using 2" blue foam and cork. I use this caulk to clamp my tortises to the foam too.
Try Aileens Tacky Glue, cheap, found in craft stores, grabs fast, and I find I can remove the track later by prying it up with a putty knife…w/o significant subbase damage. curved flex will still be a gonner, but switches can be “recovered”. Note I have used this for track and cork on plywood and masonite (for a helix), but not foam.