My new layout will be an HO branchline in the flat prairies in 1949. Little in the way of hills, just ditches Etc. Here is what I am thinking.
1X4 framing, 1/2 inch plywood, 1 inch foam, branchline size Homabed, Central Valley tie strips. Turnouts will be #6 or larger Walthers Shinohara as that is what I have on hand from the old laiout.
Would we still prefer latex caulk to hold it all in place? Would these items be a good combination?
Bruce,
I would encourage you to think in terms of resistance to warping as opposed to strength. The layout you propose will be pretty light so there is no need to go overboard in terms of strength. The one material I would remove from your list is 1/2" ply. Either go without ply altogether, or go with 3/4" birch as it is less prone to warping. Here are some options:
Grid of 1x4’s on 16" centers with 1.5" or 2" foam. No ply. Lay track on the foam.
Grid of 1x4’s with 3/4 birch ply for the sub-roadbed and foam for scenery.
Hollow core doors with 1’’ foam glued on top
2" foam set on shelf brackets. No wood at all.
Lance Mindheim
Visit Miami’s Downtown Spur at www.lancemindheim.com
Bruce, I would say that all of what you propose is just fine provided you take into account the properties of the product and how it will be affected by the environment. Is your layout space climate controlled for the most part…swings in humidity not likely to vary by more than, say, 20%? As Lance hints, warping, and not just in the plywood, could present a major headache for you after two seasons have passed if you don’t account for humidity, but also for general construction principles as they apply to the materials severally and as a contributory whole…how they work in concert.
I am a big fan of using caulk, but it only has so much hold if the materials will be aggressively affected by substantial changes in either temps or humidity. I do control my humidity, and my 1X4 and MDF spline construction has been unaffected by anything else as far as I can tell. I have no split lumber, my layout has never let out a groan or a sharp crack…not once. I did bring it all into the space and let it sit for about a week, spread out so that it was exposed to the basement air. It was only outside for minutes while I cut the lengths, but then back in it came and I erected the whole over about two weeks. Splines another 8 or 9 days. It is now 4 years old. Nothing painted, and the Atlas Code 100 is merely caulked to the top of the roadbed and then ballasted.
-Crandell
Lance’s second option sounds good to me, using plywood only under the track, with foam only for the scenery. Option one is good, too: I’d opt for the 2" foam, and use a hot wire cutter to form the ballast profile, subroadbed and trackside ditches all in a single pass. Another choice would be a similar framework of 1"x4", with 3/4" plywood roadbed on risers, and scenic contours done with wire screen and plaster.
Wayne
Never been a foam addict. My current Santa Fe layout was started in 1984, 3/4 ply with homabed roadbed, mixture of handlaid and flex track, here we are 26 years later and I have not had any problems. The layout is a three deck layout. The basement is climate controlled which of course weighs heavily in favor of the layout.
Works for me, and I am sticking with it as I don’t foresee any major changes in the future.
Bob
The only thing I could add to Lane’s suggestions are rather then using 1x4 dimensional lumber consider using 3/4" birch cabinet grade plywood screwed and glued for your bench work.Depending on the size of the layout it may be cost prohibitive but plywood definitely has some advantages over dimensional lumber one of them being your virtually guaranteed to get perfectly straight pieces where as sometimes if your dealing with the big box stores you’ll spend half a day looking for straight pieces.and plywood is less apt to warp then dimensional lumber. @ an approx cost of lets say $50.00 per sheet which will yield you 12 pieces at a cost of $4.16/piece probably not much of a difference between it and dimensional lumber. I do agree that the plywood subroadbed is a much better way to go then foam just my o/p as I have very little experience with extruded foam and only use it very little for scenery and in fact am in the process of removing it from one of my yards where I used for a base material. Too much sound reverberation for my taste but the biggest drawback I see with foam it that it doesn’t take much to dent it. A misplaced elbow or hand may cause you more work
Latex caulk is definitely the way to go but the one thing is you need to specifically use Latex Adhesive caulk such as DAP3.0 I had a friend use latex caulk after I recommended it and told him how satisfied I was with it. Well he calls me up one night reading me the riot act telling me this stuff is junk you don’t know what your talking about it’s been down for two days and still isn’t dry. I asked the rocket scientist reject to pick up the tube and read it to me. Ah ah non hardening permanently pliable caulk Duh! So it’s very easy to pick up the wrong stuff but can say I think you will be both very happy and impressed with it. You can also use it to hold down your scenery foam also.
My layout is built of “dominos” or sections, 2’X4’, 2’X6’, 2X8’ or something in between if the space demands it. I make the basic box out of 1X4 lumber. Many people advocate using strips of plywood for this because it’s perfectly straight and more stable than dimensional lumber. I’ve never had a problem with 1X4 dimensional lumber. I hand pick it at the lumberyard and let it sit in the basement for a while before using it. The basement is temperature and humidity controlled. I put short pieces of 2X2 in the corners to brace them. I put cross braces of 1X4 between the sides, one for a 4’ section, 2 for a 6’ and 3 for an 8’. Before installing them I drill 3 holes with a hole saw for the wires to pass through. I top the box with 3/8" G1S plywood. Everything gets glued together with yellow carpenters glue and screwed together except for the top which is nailed on with lots of nails. Then I paint every surface. This keeps moisture in the air from getting into the wood and looks better on the exposed parts. I paint the under side white to make it easier to see the wires and to give me a surface to write on with a felt pen to identify locations, connections, etc. Legs for the freestanding sections are just 2X2s fastened on with carriage bolts. There are probably better ways to make legs than 2X2s but it works okay for me. It just means a lot of searching through piles at the lumberyard to find straight ones.
I attach a layer of 2" foam to the top with latex caulk. It works better than wood glue because wood glue can’t soak into either the foam or the paint to make a good bond. I like the foam because it’s easy to cut into for rivers and below grade scenery. It’s also easy to make a hole to accommodate Peco switch machines. The plywood underneath gives me something to mount under track switch machines (like Tortoise) and to attach terminal strips to. I paint the foam with the same brown paint that I used on the wood because if there’s any gaps in the scenery material or if any rubs off, the
I forgot to mention the roadbed. I draw the centre line for the track with a felt pen and glue cork roadbed onto the foam. If, after I get the track laid, I find that the track doesn’t exactly sit in the centre of the cork, I’ll either carve some away with a knife or glue a little piece on where the ties go over the edge of the cork. That’s not a big deal and the ballast will cover it anyway. BTW, I model in N scale.
I don’t think Latex adhesive caulk will work to hold the tie base to the Homa-Bed roadbed very well unless you seal or paint the Homasote product first.
I like the 1" x 4" idea. However on the top I would go with either Plywood or 2’ foam. Working through either the Foam or Plywood is easy, but working through Foam on Plywood is a royal pain in the jewels. I have a small area of my layout where I have Foam on Plywood and my eyes go heavenwards every time I have to go through in that area.
How large is your layout to be? I really like spline and on anything larger than say a 4’ x 8’ it can be a real money saver and it offers a lot of flexibility with little waste. With spline you don’t need cork or foam roadbed as you just stick the track to the spline and contour the outer edge. If I build another layout I will use caulk alone to hold the spline to the risers. I think this would allow the trackbed to float somewhat above the main bench, if I were to ever have expansion and contraction problems.
Putting spline on open grid allows you to use any or all methods of landscaping, and up until the landscape is in, you can stand up in the middle of your benchwork to work on the track laying and electrical.[:)]
Brent
I follow topics such as this one with extreme interest and I thank you for raising it at this time; this is in view of the fact that, unless my financial situation improves dramatically, my forthcoming layout is going to be the first I have ever had to construct in a non-environmentally controlled environment. I am conscious that I am probably going to have to adopt some new/different techniques for my benchwork and trackwork on this layout. Due to certain space restrictions it is also going to have to be modular and portable–and, unless someone can come up with a better plan, is going to be built utilizing two 54" X 72" and one 54" X 54" open grid box frame “dominos(?)” stored vertically on roll-away A-Frames.
Here in the desert southwest soggy days are relatively rare with humility usually somewhere between 9 and 15%; temeratures range from a normal high sixties daily in wintertime to 100+ in the summertime–temps of 115° are not uncommon but temps over 110° are really not that common and are encountered mostly between mid-July to mid-August. These high temps tend to boil off high humility. Storage for these “dominos(?)” will be in a shed in the shade of a covered carport–since shade tends to be about 20° cooler than in direct sunshine I anticipate that these “dominos(?)” will be exposed to a high daytime temp of 80°-90° with very low humidity. The big problem is going to come in the wintertime where the undercover temp is likely to hover in the mid-50s in the daytime cooling off to an ambient 35-45 degrees overnight.
Although I have followed the growing popularity of foam I tend to be a little hide-bound–if it works I stay with it. I have always used a “sandwich” of 3/8" plywood sub-roadbed–1/2" Homasote®–cork roadbed with ME Code 55 track. I use Hydrocal®/crumpled newspaper hardshell for scenery. In view of postings here on the forum outlining the deterioration of cork–I