I’m looking for some beginner’s guidance on how to secure track and cork roadbed to a 2 in foam base. The caulking method seems to be the way to go, but all the photos I’ve seen use a gray color caulk. Wouldn’t it be better to use a clear color caulk?
How much time do you have to adjust the track once you lay a bead of caulk down and spread it smooth. And once you lay the track, what is the best method for getting it as straight as possible?
Also, what is a good technique for drawing accurate track lines on the foam base?
I use DAP Alex Plus Acrylic Latex caulk. It comes if a variety of colors and is only $2/tube at Home Depot. White and clear are usually what they carry.
The key to using latex caulk is to spread it out thin with a putty knife - i.e. ~1/32" thick - especially if you are laying track. I like to use a lighter color like white because 1) that’s what’s readily available and, 2) I like to be able to see the caulk as I apply it.
DAP Latex caulk starts to set up in ~40 minutes so figure 15-30 minutes of working time. For alignment, I like to draw my alignment lines BEFORE laying down the caulk. Sometimes I place a series of push pins in my foam or cork as an alignment aid for my cork or track.
A good metal rule (e.g. 12", 24" and 36") is also a alignment good tool. Place the rule parallel to the rail and move the track until there isn’t a gap. However, your eye is your best alignment tool. Even if you use a metal rule, run your eye down each rail to see if the sections are indeed straight. Sometimes I go back and forth adjusting the rail in small increments until it “looks” right.
Since Tom pretty well covered the waterfront, I’ll just add a few comments:
Why grey caulk? Because most modelers use grey (or close to it) ballast, and the caulk will hide the ‘holidays.’
Anchoring the track until the caulk sets - I use ‘miscellaneous weights’ (phone books, canned goods batteries from battery-powered tools.) A 16 inch length of 75 pound/yard rail is gross overkill!
Actually, I use caulk in three layers - thin extruded foam (aka fan-fold underlayment) to plywood, cardstock track template to foam, flex track (or wood ties for hand-laid specialwork) to cardstock. The bottom, totally invisible layer can be any color, even royal purple or neon pink. I use whatever was cheapest at Home Despot or (Madden’s) Hardware last time I visited. For the cardstock layer I prefer clear, so I can see the guide lines for the template. The final layer is grey.
Chuck (Modeling Central Japan in September, 1964 - on foam-anchored trackwork)