Am curious… Before I continue with my track-work, I would like to know what differences exist re using latex caulk to adhere flex-track to cork roadbed, or using ballast as an adhesive. What, if any, are the dis/advantages with either method? Thanks for any tips/suggestions you guys may have.
G’ Flash
Ballast, as such, is crushed rock (or crushed walnut shells, if you use the Woodland Scenics product.) It has no inherent adhesive qualities and will not hold track (or anything else) unless some form of adhesive is used to bond it.
Latex caulk IS adhesive, so laying flex track (or the ties for hand-laid) on caulk will anchor it forevermore, or until someone slips a drywall knife into it edgewise to deliberately raise the flex track for re-use elsewhere.
Latex caulk goes down before the track. Ballast is added after the track is in place, and (hopefully) run on and adjusted as necesary. Until the track is ballasted, it has to be held in position with something: track nails, spikes, Gorilla glue…
It is possible to use latex caulk to secure ballast - just lay it on a little thick and press the ballast into it.
It is not possible to use ballast alone to secure track, unless you’re working in G-scale or larger.
Chuck (Modeling Central Japan in September, 1964 - on multi-material roadbed with lots of latex caulk)
Yeah, I agree…it isn’t really an either-or situation. I think you can use ballast to keep your flextrack or snap track in place, but you would want it well anchored while the ballast is setting up. That means pins, track nails, or something like a thin skin of latex caulk below the ties.
I have never placed flex against sub-roadbed of any kind ‘dry’, with the two surfaces, plastic ties and roadbed, juxtaposed tightly, to see how noisy they are…ballasted or not. But it stands to reason that a thin layer of caulking between the ties and the roadbed, no matter what it is, provides the dual density layers the acoustics folks say is optimal to attenuate the sound waves. So, why not kill two birds with one stone…fix your carefully formed track with the caulking, and then ballast it lightly, glue it lightly, and enjoy the benefits of all that each material offers you?
I use MDF spline roadbed, thinly spread with caulking, the rails applied, and lightly ballasted. My road is quite quiet. And nuthin’ moves.
-Crandell
Thanks to both of you guys - Chuck and Crandell… I kind of thought there was a good reason for using the latex caulk between roadbed and flex track. It requires some tedium, but, I think the results will be worth the time and effort. Thanks again…
G’ flash
An interesting question, Flash.
I think most modelers use caulk or glue to hold their track to the roadbed, then ballast it afterwards, more for appearance sake.
Years ago, I experimented with powdered resin glue, normally used in woodworking. I mixed the dry resin glue with the ballast, then applied the ballast to my track which was lightly pinned in place (either track nails or straight pins). Using a very fine misting spray, I thoroughly soaked the ballast. When the ballast dried, I removed the nails and pins. Only the ballast secured the track to the roadbed.
Some time later, I moved and dismantled the layout. It was fairly easy to remove the track using a putty knife. Getting the ballast off the track itself was more problematic. A few years ago, I found a short section of track from that layout from 25 years ago. It still had ballast on it. I tried to clean the ballast off and it was just as difficult to remove then as it had been 25 years before!
The resin glue is activated by water, but once it dries, water will not dissolve it. Oddly enough, if you can re-powder the resin, it can be activated by water again, although with a weaker bond. I like this method because I can take a long time getting the ballast just right, then spritz with water to start the hardening process. The rails stay pretty clean because only water gets on them. I never have to clean any glue from the rails after ballasting.
On my current layout, I used the same ballasting procedure with resin glue. In operation for almost 6 years and the track is still held tight to the roadbed. Resin glue is fairly expensive when compared to white or yellow glue, but I like the way it works for me.
Darrell, quiet…for now
In my opinion, the disadvantage of both methods is the inability to easily make adjustments in your track after you have made a few test runs over an extended period of time. I’m not talking about adding or removing turnouts, or wholesale changes in the track plan, but simple, minor adjustments to smooth-out a curve, re-align a track for better clearance around some trackside obstacle, or otherwise improve the operating characteristics of your track.
I suspect that the use of caulk as a track adhesive is an outgrowth of the use of extruded foam as a layout surface, and while it is an effective solution for keeping the track in place, it doesn’t give you much leeway for those minor adjustments than can have a big impact on how well your trains will run (stay on the track). No matter how carefully you lay your track, you won’t really know how well it will perform until you’ve had the opportunity to run some trains over it.
As for deadening the sound, it seems reasonable to expect that the caulk would have some benefits, although my track, on both cork roadbed or directly atop plywood, nailed down and with ballast glued in place with white glue, doesn’t seem excessively noisy to me. If the noise is too much, it may be time to just park the trains. [;)]
Wayne