This is my first post to this forum, so pardon me if it is nieve pr redundant. I am using Sievers benchwork for the foundation of my layout. On top of that, I was planning to put 1/2" OSB, followed by 2" foam. I plan on using foam products, such as those from Woodland Scenics, for all of the scenery, elevated areas, inclines and risers. The questions are… 1) is the 1/2" OSB really necessary and 2) if it is necessary, what is the accepted way to attach it to the benchwork…nails, screws, glue, all three?
alfanz- Welcome to Trains.com! [C):-)]
The LION takes many shortcuts that would be unapproved of here. OSB board does have a grain, so you want to mount it with the long chips spanning your ribs. That said, the LION dispensed with it entirely and just mounts foam or Homosote directly on the table grid. These are HO scale trains. If they were 1:1 I’d consider the heaver construction.I was just in my local hobby shop (LHS) today and he was building a huge helix using fine birch plywood, several orders of magnitude better than OSB. If you use foam with your OSB, even 1/2" foam, this will not matter, but it is not nice to mount tracks directly on OSB for you need a far smoother finish for that. (OK, the cheap LION did just that anyway, but maybe you want to do better).
[Homosote, these days, is not of the same quality as it was in the past, for now it is shipped with 2x4s under a stack of the product and it develops a sway-back that is unacceptable (at least to this LION).]
Two Inch foam is very adequate to support a layout all by itself. But maybe you do not want to do that either for many reasons, first being that you may want to remove foam where a river or other feature may be or even a route running below grade level.
The best reason for putting the OSB (or plywood) first is that you can cut out a line that is rising and lift that part of the board from below using risers mounted to the table grid. (Called a “cookie cutter”) I did that with my second layout and it worked perfectly, On this, my third layout I did not need that, and I took the risers away and lowered that strip back down to the table level and braced it with cleats from below.
The Mounting of switch machines is another consideration, which is why I went with pressed board rather than foam for most of my layout. My layout seems stable enough without the OSB and with just a Homosote like product as the only deck. This too has advantages as nails do not hold well in the foam. But once you glue down a cork roadbed, this may not matter. Except for
Nails, screws or glue…
Nails are basically out. Wood expands and contracts with humidity in the atmosphere, and this will loosen the nails. (Besides, banging on the layout with a hammer is the equivalent of a 5 on the HO Richter scale) The LION built his layout with screws only using drywall screws driven with a Phillips head bit in a variable speed drill. The glue will give you much greater stability but you will curse at it if you have to change things. The LION changes his mind weekly (hangs the spare one out to cool off) so, since this is your first major attempt at a layout, I’d forgo the glue, because a few years down the road you may want to take something apart and arrange something differently.
ROAR
Welcome to the forums.
I am not familiar with Sievers benchwork, other than knowing that it seems to have a very good reputation. I would think that a good solid frame underneath 2" foam would not require any additional support. A number of layouts talked about here on the forums have had good results with the foam being supported on 16" and 24" centers. Ii would say the OSB would be unnecessary.
If you go to the right hand column on these pages and scroll down to Search our Community, you can do a search for Sievers and see what others have had to say.
Good luck,
Richard
While I am not entirely sure what you are getting at here, that never prevents me from stepping in and opining. I think the best option is to elevate the track but not over the entire benchwork so that the elevated track gives you some scenic options to dip below track level here and there.
Once you have a basic table top, which I think you get wth the Sievers benchwork, then I think the issue is what options you want for topographic variation below the level of the rail. I am talking roads, rising to grade crossing level, culverts, creeks, and other such features, as well as the normal rise and fall common to any urban or rural scene.
That is, basic cork roadbed on top of benchwork elevates HO scale track about 1’4"
That is not really enough for culverts beneath the track, and much variation on what constitutes “ground zero.”
1/2" homasote subroadbed, beneath the roadbed only not covering the entire table top, adds about 3’9"
Now we are getting somewhere.
What I am trying to say, perhaps not very coherently, is to not just take a 2’ by 4’ layout section and cover it with slabs of 2’ x 4" foam or plywood or homasote, but rather think in terms of a contour map. If the table top is absolute ground Zero, what elevations do you want before the top of track exists?
Dave Nelson
First, [#welcome] to the forums!
I, too, did not know what a “sievers benchwork” was but i looked it up on google. Nice idea.
I used an open grid with 1 bys on a 12 inch-on-center grid and glued {with Gorilla Glue} the foam directly to the open grid.
If you are sure you are not going to ever use something like undermount switch controllers {Tortoise and the like}, or track nails to hold your track, then you should be OK just gluing the foam to the grid…
If I had it to do again {and I am sure I will} I would use at least 1/4 luan plywood or plywood with a good grade side as a base to put the foam on, glued with Gorilla glue of course. {Gee, or did i use ordinary white school type glue? Now I wonder}
I would NOT recommed the use of OSB or MDF. MDF is reportedly had bad results with gluing and wetting and absorbtion of moisture an warping. I would expect no less of OSB, but I could be wrong. I know OSB will attract moisture and can bubble, even though there is lots of glue in it to hold it together. {my floors are a good/bad example}.
{White glue, Foam glue or FOAM safe latex caulk can be used to secure the WS foam scenery to the foam board}.{again I think I used plain white glue and I know I held everything down with several mini Ziploc bags of sand on top until dired.}
Good luck and [#welcome] to the hobby!
[8-|]
I am constructing my layout using Sievers. It does not have any track grades or large variations in topography; therefore, I covered the bench framing with 1/2" B/C plywood and covered the plywood with 1/2" Homasote.
The plywood is secured with screws spaced at 12" o.c.; the Homasote is secured to the plywood with screws spaced at 12" o.c. Plywood panels are the sized to the Sievers sections; Homasote panels are sized so joints do not coincide with Sievers/plywood section joints.
All benchwork framing, plywood and Homasote is painted all sides and edges (although the layout is in a climate -controlled room).
I am applying Homabed roadbed using brads; the roadbed will also be painted. Walther/Shinohara track will be spiked, and because I am using 1/8" Homabed and the spikes are about 3/8", they will help secure the Homabed to the Homasote.
No glue is used anywhere to facilitate the possibility of disassembling the layout and moving track.
So far, so good!
Dante
PS. I purchased the plywood and Homasote from a reputable, traditional lumber yard (not big box) that cut the panels to size for a nominal extra charge. The panels were of high quality without major distortion. Slight warping that resulted from painting was easily eliminated by the screw attachment noted above.
You don’t need anything but the foam!!! I don’t use their benchwork but mine is homemade the same basic way and I just caulk the foam down.
I would recommend using a sheet of 1/4 inch or so Luan on the benchwork and then putting your foam sheets on top of that. Buy using the Luan, you will have a wood surface on the bottom that will aid mounting switch machines and their linkages to. The Luan ‘bottom’ will also be there as a safe-guard in case to cut too deeply in your foam and go through it.
If you use only foam, you will have to provide or glue on Luan squares to the bottom of the foam to hold the switch machines. This will work but will slow you down some. You can use 5 minute Expoxy to glue these small sections of wood to the foam.
Two inch foam board is plenty strong enough to hold up the trains and the scenery. It’s strong enough to take anything short of climbing upon it. As long as you don’t need to climb up and sit or stand on the foam, it is strong enough by itself.
The reason many of us put plywood under the foam it to give something to hold under table switch machines, wire looms, and anything else that wants to be fastened to the under side of the layout. Foam does not hold fasteners of any kind, so everything attached to foam must be glued to it. If you have a sheet of plywood under the foamboard you can screw everything into the plywood. Plus, a solid plywood base gives you something to glue the foamboard to. And, a solid plywood top adds great strength and stiffness to the underlying benchwork, legs, L-girders, and joists.
Either you can secure the plywood to the tops of the joists with a bead of construction adhesive (Liquid Nails) and a row of sheet rock screws running down thru the plywood in the the joists, OR, you can construct “dominos” , shallow wooden boxes with 1by 4 sides and a plywood bottom. I machined a groove in the sides to accept the plywood and put the domino together with wood glue.
Oriented Strand Board (OSB)is cheaper than plywood and not as strong or as nice to work with as plywood. However it is cheaper and house builders use it for subflooring. I’d use it if I was saving a lot of money. I’d be willing to pay a reasonable amount extra to use decent plywood, but that’s a cost benefit tradeoff we all have to make depending upon market prices at the time and the state of our wallets. I would not use Medium Density Fiberboard (MDF) because it’s just glued together sawdust. It isn’t very strong, the grit in it dulls your tools, screws don’t hold very well in it, and it is very heavy.