nailing plywood and homosote help

Newbie question, I know. I’ve got my benchwork set up, thanks to the fine folks at Sievers, it was a snap. Now, I want to have half inch plywood with a half inch of Homosote as the base for the layout. What type of nails should I use to nail the plywood to the benchwork? And what do you recommend I use to fasten the Homosote to the plywood? These kinds of beginner questions are hard to find answers to sometimes, so I’m glad you guys are out there willing to answer them.

Thanks,

Mike

I wouldn’t use nails. I use "drywall’ screws. I also try to screw the plywood to the benchwork (risers) from below so that I can take it apart and change things if I want.

I attach the homasote to the plywood with drywall screws and glue. After the glue dries, I remove the screws. Any holes get covered with ballast or scenery later.

Dave H.

Although homesote was a standard for years it’s really hard to work with. You might want to consider trying the blue foam insulation board and cork roadbed instead. the blue foam is a lot easier to work with. If you are determined to use homesote then instead of nails, use liquid nails and “glue” it to the plywood. I never nail anything, it’s just too easy to split the wood. I use a #6 countersink bit, drill a hole, and then use wood glue and 1 1/4" sheetrock screws instead of nailing. … please check out my website i have a section in “trains one” on building benchwork. i don’t use homasote or blue foam because my layout is built on cleats and risers www.webshots.com/user/bayouman1 chuck

Never, ever, use nails to attach subgrade or roadbed, and be very careful when using track nails with flex or sectional track. If, like most of us, you start running trains before all of your subgrade and roadbed are in, every hammer blow on a nail used for structural attachment will be about 8.3 on the Richter scale to your already-modeled work.

In addition, you can’t re-tighten a nail. If, as suggested, you use drywall screws driven up from below, you can always snug them up to compensate for wood shrinkage due to humidity change.

Chuck (modeling Central Japan in September, 1964)

OK, so it sounds like I’d be fine with just using 5/8 inch cabinet grade plywood and cork roadbed on top of that and skip the Homosote? I agree with the screwing from below, however, I have 1x4’s every 12 inches as crossbeams. Wouldn’t I need 4 or 5 inch long drywall screws to drill through those 1x4’s? Guess I’m not understanding how I could screw the plywood from below, at least the way my benchwork is constructed. It’s Sievers benchwork.

You don’t have to secure it from below. Just lay the plywood on top of the cross members and drill a hole and screw them thru the plywood and into the 1 X 4’s below the plywood. If you don’t like the holes than there’s always wood putty to fill them in but the ground cover should take car of that. Be careful where you put your turnouts if you plan on using under the table switch machines. A turnout’s points positioned too close to a 1 x 4 and the machines won’t fit under the turnout.

You might want to pick up the Linn Westcott / Kalmbach book on building model railroad benchwork, a lot of your questions will be answered there.

For attaching the top to the benchwork, you need “cleats” of 1" x 1" wood, maybe 2-3" long. It’s a little hard to explain without being able to show you a picture or draw a diagram. Some screws go thru the cleat into the plywood, other screws are at a 90-degree angle and go into the joists.

Think of it this way…turn everything upside down, so your plywood is face down on the floor, and your benchwork is laying on top of it upside down. Where the joists meet the plywood, there’s an “L” shape formed. Put the cleats inside the corner of the “L” and use glue and screws to attach the cleats to the horizontal part of the “L” and the vertical part of the “L”. Usually just a couple are needed.

That being said…if you’re going to use say Woodland Scenic risers so you know you’re never going to cut into the plywood, you could just as well do the screws thru the top, as long as when you drill the holes you make sure you countersink the holes so the screwheads are flush or below the table level. BTW think about elevation before laying track, if you glue your cork roadbed to the plywood, the only way to make grades or scenery below track level will be to cut the plywood and remove part to allow you to ‘build down’ to a lower level for say water going under a bridge etc.

wjstix is explaining “toeing” a board. set the 1 x 4 on top of the L girder and insert the screw thru the board and into the L girder at an angle. Put two screws in. One on one side of the 1 x4 and one on the other side of the 1 x 4, both at an angle. A little wood glue between the boards won’t hurt either.

I wouldn’t waste money on cabinet grade plywood unless you’re planning to finish it as a piece of furniture, with no scenery. Spruce sheathing plywood will work equally well for half the price, and 3/8" will be plenty strong for your benchwork. Don’t worry too much about driving the screws in from the top side of the plywood: except for those very few who have a very well-thought-out plan, most layouts are not disassembled down to their original components. I have mixed feelings about the layer of foam that some have mentioned, too. While it can be useful if you want to make some areas of scenery that are lower than the track, I’ve seen too many instances where it was included merely as a matter of course, because “that’s the way it’s done”. It’s merely an added expense if you make no use of the advantages it can offer. Many say that gluing the cork to the plywood sub-roadbed increases the noise, negating the sound-deadening benefits of the cork. I don’t notice any problem in that regard, but some people advocate the use of latex caulk as an adhesive, in order to prevent excess noise, and even use it to fasten the track to the cork. I glued my cork in place using yellow carpenter’s glue, then used 2" nails (I had lots on hand[:)] ), driven through the cork and partway into the plywood to hold the cork in place and keep i

Hi Mike,

I think you should stick with the plywood/homasote idea. To glue down the Homasote, use a tube of liquid nails (it fits into a caulking gun and if you don’t have one, they are a couple of dollars). I like the Homasote because it helps to reduce the noise of the trains AND it makes it easy to attach your cork and track because it accepts the rail spikes easily and the small nails you will use to fasten the cork to the homasote. I use some short screws to hold the Homasote down to the plywood while the liquid nails dries and then a week later, remove them, as has already been suggested.

Considering the size of your layout, you won’t really benefit much from using foam as a cover over the plywood. It will be easy to build up areas you want with other methods.

By the way, you should add your email address to your account so we can email answers to your questions also. Sometimes, I’ve given newbies my phone number to call so they can talk to me directly with questions. I’ve walked several people through their problems on the phone, which is easier than the forum. I wouldn’t post my phone number for obvious reasons.

Hope this helps.

Well, you have guys pulling your sleeves on both arms…so what are ya gonna do?

I would like to know why you had considered homasote at all, and if not using it would clearly compromise your intended effect(s)? How would you determine that…by asking here?

One thing for you to consider is that a given density of material in a given type of material will propagate sounds of a given frequency better than other frequencies. Engineers and physicists have long since learned that when you jam materials of two different densities together and then try to propogate sound waves through this new “composite or layered material” the sounds do very poorly. That is why homasote was used, moreso in years past, but there is no reason it cannot be used to good effect today for the same reasons as yesteryear. The physics hasn’t changed.

So, you can indeed use homasote atop plywood and get the desired quieting with its resultant dual density interface, or you can just lay cork atop the plywood and get a somewhat cheaper and much less messy outcome. Or, as suggested, use foam instead, and the cork will still provide that dual density you crave.

Just something to think about.

May I put in my nickel’s worth…

Whether you go the homosote or cork or whatever, I strongly urge you to use sheetrock screws or deck screws for the plywood or whatever else you had intended to nail.

I completed the benchwork on my current 15x11 (3 level) in the early '90s, and it is entirely afixed with the screws. I used two cordless drills, one with a 1/8 inch bit to prevent wood splitting, and the other with a screw tip.

This method made it much easier to get the heights, and other joints just right, and what errors were made were easily adjusted. I would not attempt building a layout with nails.

Using brads or the like for holding cork or homosote down while the glue dries is something else of course, and for the record, sheet cork (1/8) works just great over plywood.

Mobilman44

I think homasote is a great material for yard areas. I spread carpenters yellow glue and use 1" drywall screws about every foot until the head is depressed below the surface of the homasote. I’ve never had kinks or shrinkage. I raise my mains with strips of the cheapest paneling I can find. Most Home Depots or equivalent have a real cheap line that is in the $4.00 per sheet range. Damaged can be had even cheaper. I rip it in 1" strips for HO which gives usually 47 strips 8’ in length per sheet or 376 linear feet. Then I stack them on thier sides and slot them about every 1/2" so they can be easily bent to a 30" radius for HO. I use small 3/4" long brads wth heads to nail that to the homasote. Why do I do that? iT makes the transition to the grade level easier and looks more realistic to me than the height of cork. It also is the perfect width to give nice shoulders on the sides of the ballast. The homastote underneath keeps the noise levels down. I am not a fan of foam as you are completely dependent on a glue joint to keep everything from falling apart track wise. That is why there are Fords and Chevys. To each their own and there is always one more way to do things in this hobby. It’s no different from those who profess you have to use DCC while some of us get along fine with plain old DC.

Plywood to supports, drywall screws. Homasote to plywood, small finishing nails at an angle. After that, I do not nail anything down with a hammer. Press in track nails.

Homasote is not difficult, if you use a razor knife and just make easy cuts. After the first cut the blade will tend to follow the original cut. I like Homasote.

I don’t mean to hijack Mike’s thread but I figured that it was better than creating a new thread on the same subject. Sorry Mike.

I’m having trouble understanding the use of homasote on a layout bench. What is it used for? Is it used as a substitute for cork roadbed? What are the advantages of using homasote instead of cork? Is it laid in 2" wide strips split down the center like cork? How do you bend it to form curves? How do you bevel the edge? Or does it lay in sheet form, flat on top of the plywood, completely covering the bench from corner to corner and the cork roadbed goes on top of it?

I’ve always glued cork roadbed directly onto the plywood never considering any other method. I imagine that homasote may provide noise absorbtion that’s carried through the plywood as trains pass over it but I cannot think of any other reason to use it.

Hi Ted,

To answer your questions, first, the Homasote deadens the sound, as mentioned above but more importantly to me, it is easy to spike the cork and rail to it. Your last sentence got it right, you cover all the plywood with Homasote and later draw your lines for the track and place cork down on top of the Homasote. I use Atlas track nails to put down the cork on the Homasote and then rail spikes to fasten the track to the cork.

By the way, there’s a company that makes transition shims to get from the level of the cork down to a yard or siding, where you don’t want elevation. Here’s the link.

www.homabed.com

On my first layout, I didn’t know about the Homabed shims and therefore had my sidings on cork also. The shims can be cut to the exact height to match your mainline and then they transition down to “grade” in about 9 inches or so.

Hope this helps.

Mondo

Homasote is usually used as roadbed in lieu of cork, although it has also been used in many other ways. The traditional way to use Homasote is to cut it into about 1.5" wide roadbed sections and glue/screw it to plywood subroadbed. Most folks doing this cut the plywood away (cookie cutter) except where the track/Homasote is going to go. This allows the scenery to easily extend below the track as well as above it. The only good reason I know of to leave the plywood intact on top of the benchwork is if you are constantly rearranging sectional track on the table. If that is the case, you probably won’t want to use any roadbed - Homasote or cork - until you arrive at a more or less permanent track pattern.

For curves, some cut kerfs in the outer edge to allow the Homasote to flex around the curve. I just cut the curve from a sheet of Homasote like I did with the plywood. It does create more waste, but I don’t have to deal with cutting or filling kerfs. Beveling the edge can be done by setting the blade angle when you cut Homasote, although I have never bothered. I make the plywood subroadbed wider than the Homasote to give a place to tie the scenery shell. If I want a lower roadbed profile, I simply build the adjoining scenery higher.

The primary advantages of Homasote a

Thanks for the link mondo. Now, if I can only find pictures to see what they look like. I also wouldn’t know which ones I’ll need as I see that there are many different types.

I recommend use of both glue and roofing (wide-head) nails. Nails hold down the homasote while the glue sets and give another level of assurance that the homasote will remain stable. I’d also recommend painting the homasote as a moisture barrier. Be very liberal on the use of nails, but make sure you avoid spots where you might use a spike to hold down the track or at the location of turnout throw-rods if you’re using subsurface switch mechanisms. Also, the nails should not be so long as to poke out the bottom of the wood sub-roadbed unless body impalement appeals to you.

Mark

Its not “toeing”. Its making a cleat. Two different things. With a cleat all the screws are at right angles to the wood.

What I do is make a “riser”. The riser has a vertical part that is a 1x4 with a horizontal part or cleat that is a 1x2. The 1" side of the 1x2 cleat rests against the 4" side of the 1x4, making an upside down “L”. The 1x2 is glued and screwed to the 1x4.

If you are using L girder or open grid consrtuction, there will be crossmembers which are called joists. If you are facing a wall the L giders or front and back sides of the grids run left and right parallel to the wall. the joist trun on top of the L girders or between the grid sides from the wall out towards the aisle.

The risers attach to the joists. The plywood or roadbed rests on top of the risers. The cleat is up against the bottom of the roadbed. From the bottom you drill straight up through the cleat into the road bed (do NOT glue the riser/cleat to the roadbed or the rider to the joist). But varying the height of successive risers you can make the roadbed ascend or descend. If you want to change the grade or elevation, you can unscrew the risers from either the joists or the roadbed and alter the layout. Where there is a broad area to be supported, such as a yard, I make a rider that has a 1x4 on each end with a cleat that goes all the way across the bottom of the roadbed.

I have been using this method for over 30 years on dozens of private and club layouts and can attest to its flexibility. When I rebuild my current layout I will be increasing the height of my risers by 6-8 inches to gain more open space between the open grids and the roadbed to recess the car card pockets and pushrod controls, maybe even a work surface or two.

Dave H.