Years ago MR had an article about using Mycor 300, a US Gypsum product, in place of plywood or other roadbed. It is apparently stable through any humidity changes; very easily accepts spikes or nails, but holds them firmly; has a very smooth surface; and is quieter. Only problem was cost.
50% lighter than particle board. Plywood weight, maybe lighter than that even?
They make a lighter version known as Micore 160 which is less dense and maybe more suitable for our use.
Plasterboard reinforced with “inorganic” fibre. Also described as “mineral fiber”
Probably needs benchwork framing to keep it flat.
TM name is Micore.
I’d want to be very sure this stuff did not cause accelerated wear to saw blading or router bits due to the ‘mineral’ content, or that fine-cutting dust didn’t have the equivalent of fine fiberglass dust, short little inorganic fibers to cause persistent itching or worse.
I am building my second n scale layout. Have layed the track and am ballasting now. I used caulk to fasten the track down on my first layout and I did not like that. It was messy, difficult to get the track positioned, took a long time to dry, did not always stay in place and hard to get the track up if a repair needed to be made. So on my second (current) layout I decided to temporarily nail the track down using a tiny drill and small nails. This allowed me to make sure the track work was where I wanted it and was working. After ballasting I am pulling the nails out and painting overthe holes. The ballast and white glue hold the track in place nicely. Don’t waste your money on caulk.
I’m in agreement with your comments. It seems some have the right skills to make caulk work, but the nail/spike method has worked so well for me, I prefer not to go throught the learning curve like you did and end up back with something that always worked well.
I am also a spike/nail then glue ballast guy.
I have never used caulk on a layout. Caulk on a wire armature can make for very nice tree bark.
-Kevin
I think the reason anyone finds caulk “messy” is that they cut open the tube like they are caulking a bathtub - ie, one of the rings marked on most tubes of caulk as to where to open it up. Not one video I’ve seen illustrating the use of caulk for track and/or roadbed has showed this, but the very first time I tried using caulk after a lifetime of building layouts with track nails, it was pretty obvious to me that allowing that much caulk to come out would most definitely make a mess.
I used my rail nippers to nip off the tip just far enough so that there is a hole visible. Smaller than a #18 wire. To puncture the inner foil, since the opening is goign to be too small to use a large nail or a screwdriver, a piece of solid wire works.
Now the caulk comes out in just a VERY thin line. Not so much that when you smooth it out with a putty knife (or the edge of those fake credit cards they send with credit card offers), there’s not so much that it builds up and oozes out around the tool, getting on everything.
ANd that SUPER thin layer, really just a shiny spot on the plywood, foam, or roadbed, is PLENTY to stick the track down. No muss, no fuss. ANd until you add ballast, it is easily lifted off without damage (foam roadbed on extruded foam tabletops, not so much - even a thin bead of caulk sticks those two together VERY well - so don’t expect to reuse that piece of foam roadbed - but it will come off). Track pieces can easily be reused, if applicable (if part of what is changing involves removing a 3" piece of flex - do yourself a favor and don’t try reusing that tiny bit. But if you remove a greater portion of a whole stick - go ahead and reuse. Also turnouts, they are too expensive NOT to reuse if you make a change in the track plan)
–Randy
Just for the people who might not know this, the purpose of that little locking toggle on the caulking-gun shaft is to be a quick-release for trigger pressure. It is essential to relieve pressure quickly in large tubes with small apertures; a surprising amount will keep spooling out unless the pressure is explicitly relieved…
Yes, that too - it is important to relieve the pressure after laying a bead, or indeed a whole lot of excess will continue to squirt out in a thing little line.
When done for the session, I also pull the plunger back a bit instead of just allowing it to pop back automatically. And of course cap the end.
–Randy
Also, don’t pull that trigger until you’re good and ready. Aim, ready, fire is best for caulking guns. A little practice gets you the skill to apply just enough pressure to start your bead and complete it without adding more pressure. Most track laying requires pretty short beads of very little caulk. Just barely squeezing the trigger is usually best, then pop the ratchet right as you approach the end of your bead. Same technique for household use.
2" putty knife is handy for spreading water clean up caulk if you don’t think just pressing down on the track underlay is enough. You want the caulk to spread out as thinly as possible to avoid bumps in your track. 2" putty knife is exactiy the right size to achieve that.
Also, a utility knife to cut an angled tip can help a lot. You then rotate the caulk container in the gun so as to orient the angled opening to the most useful angle to lay a flat bead onto the benchwork.
I use dripless caulk gun, for everything I caulk, windows, siding, doors, and putting down track. They work great.
When I’m done, I do relieve any pressure from the plunger, and seal the end with a piece of duct tape.
Painters tape works too.
Mike.
Ths picture below illustrates how thin the layer of caulk should be. While the caulk sets up, I either use weights or pushpins to hold the track in place. The gaps cut into the rail are for wiring the layout in blocks. I bridge the gaps with styrene glued into place with CA, then the styrene is trimmed with a new #11 Xacto knife blade.
Great pic. That’s exactly how to do it. And it will NOT come up or move on its own after the caulk sets up. But slide a putty knife in there and you can remove the track without damage if needed.
–Randy
We found the same thing. The caulk sets up fairly slowly and I’m pretty sure ballast will stick to it just before it finally cures. Our plan is to spread a very thin layer of ballast onto the curing surface of the caulk before it fully sets up. Then ballast as usual. Not at the turnouts though because any ballast stuck to caulk isn’t going anywhere ever.
A concern with ‘wiping out’ to very thin involves whether it is better to use a flexible blade, like a thin silicone bowl-scraping spatula, to make sure the caulk layer is thin and even, or a stiffer blade (including the previously-mentioned old credit card) to tool the top of the caulk smooth and level to match the crossties in the flex-track strip. You’d get more feet of track per ‘tube’ out of the former; much better lateral and likely vertical retainment with the latter. Which ‘style’ do the experts here prefer? (Note that this is a difference between ‘extremely thin’ and ‘very thin’ for most roadbed: even the thickest layer would only reach full coverage of the tie ‘footprint’ when the track is weighted to hold level for the caulk setup time…)
On foam track underlay the important layer to get smooth and thin is under the foam underlay so there are no humps. However, very little caulk is actually required. For plastic ties on top of the foam underlay so little caulk is required that the ties can be pressed flat into any slight irregularity there. Ballast will cover any slight oozing up around the ties. Because the track is pretty rigid it would not be necessary to be very precise. Making a very thin layer is desirable because you need so little caulk to create an effective bond.
The photo shows excellent work with no oozing up the ties. Note that cork underlay would make a much better harder surface to achieve that thin layer. On top of foam I would use even less caulk. You do not want any surface irregularities that might create uneven railheads.
I usually use a putty knife. The ‘credit card’ I was mentioning would be more int he category of a soft tool - not a real credit card, rather those fake ones that come in many of those throw-away offers, which are little more than a thinly laminated piece of paper, not hard plastic like a real credit card.
As for wastage - my old layout,t he 8x12 donut one, all the track and all the roadbed, except the yard, was done with one tube of caulk. I had to open a second one to start the yard. At that time, I think a tube of the Polyseamseal brand I used was $1.99. I doubt I wasted much, but even if I did, if I somehow wasted 25% I would have only been out 50 cents. Not even a consideration. I DID waste more on the last layout, because I worked a lot slower, and had to clean out the nozzle a lot. I think I used 2 whoel tubes ont hat one, partly because I found that cork roadbed needed more caulk to stick to the foam than the WS foam did on the one before that. I also indescriminately used the same caulk to fill low spots and glue other foam bits together, so it’s hard to say just what went to the track and roadbed, and what went to general construction. At any rate, it’s cheap enough that excess left over after spreading a section with a putty knife was something I just scraped off the knife on the edge of a scrap piece of wood and didn’t concern myself with. If I was using something that cost more like $5 for ever 10 feet of track I put down, I’d be more carefuil of the waste rate.
–Randy
I use contact cement to lay flextrack and turnouts. Then ballast and glue.
Robert
Contact cement is usually pretty much permanent. Have you had occasion to lift and reuse any track?
I also used contact cement to secure cork roadbed to plywood on the partial upper level of my layout, then used it again to cement Central Valley tie strips to the cork, and then to secure pre-soldered lengths of rail to the ties.
The cork was positioned to a drawn centreline, with sheets of waxed paper between the two surfaces to allow proper alignment, slipping each sheet out as needed.
The same procedure was used for tie alignment, using the centreline of the cork and centreline nubs moulded on to the tiestrip.
I again re-used the waxed paper when adding the rails, but it was a simple matter to line them up with the tieplates moulded on the ties, slipping the waxed paper out as I went along.
I’d guess that the cork could be lifted, if necessary, but not likely neatly enough for re-use. The tie strip material is fairly thin, so unlikely to come up cleanly and probably in small pieces.
The rail should be fairly easy to reclaim, but I’d guess the tearing up will be done after I’ve left the scene, with likely little interest in saving rail. Structures and trains will likely be salvageable, and might generate some cash, but it won’t be a concern for me.
Wayne