My current layout is built on 1/2" plywood with 2"x4" framing, forming a 22’x42’ P-shaped layout.
On my next layout, I would like to use 1/4" plywood because it is cheaper, lighter, and thinner, making it easier to drill holes and install Tortoises.
I don’t want to consider other alternatives such as 2" foam board or other types of surfaces. So, my question is: does anyone use 1/4" plywood and what are the pros and cons?
Looking forward to all of your comments.
Rich
Hi, Rich.
I would have to say the 2x4 framing is overkill as 1x3 or 1x4 is plenty strong for the base structure. I assume you’re doing grid type construction and not L-girder. Either way a 2x4 is heavy & cumbersome and really not needed for strength or any other reason unless you get them for free.
Personally I don’t use anything thinner for my base or subroadbed than 3/4 plywood as 1/2 tends to twist & warp unless supported about every 12" or less. As for 1/4" I would definitely recommend against it for the same reasons as for 1/2" plus it will be very noisy. I used 1/4 on a small switching layout once and found it to be totally unacceptable.
I can understand your reasoning for not using foam but I think you might rethink that and look through the many posts here and on other sites. Foam is definitely here to stay and that’s for many reasons.
You might check out some of the Kalmbach how-to-do-it books on benchwork and building layouts. They have some great ideas on what to and not to do that have been tested and proven.
I envy your 22x42 layout room! Maybe someday?
Roger Huber
I used 1/4 inch on one section of layout with 1/2 inch foam glued on top of it. I found it to be totally inadequate.
Roger,
Thanks for those comments. I have to give some serious thought to what you are saying.
That layout room is actually my basement which measures 60’ x 44’ but my wife has drawn the line and there is no crossing it.
Rich
Yikes, 1/4" plywood is 0 for 2 so far.
Yep, I agree, 2" x 4" framing was overkill when I did it, but now I have plenty of it so I will be reusing it.
The 1/4" ply would be fine if you laminated foam to it, but as stated even 1/2" alone can give you problems unless you use a quality 1/2" cabinet, AC or underlayment grade. The subroadbed for any large area should be at least 3/4" unless you want to run the joists at a closer spacing like 12". doing this will inevitably have some of the sw machines land on a joist, especially for yard ladders.
I’ve used 1/2" without regret for decades. The 3/4" is too heavy for me to handle those 4by8 sheets, it uses up jigsaw blades quicker, and is slower to cut with the usual home tools.
Mark
For what ever it is worth, close to 20 years ago I built a train table in my mom’s basement using 1/4" luan over 1x4 poplar framing. I sealed everyting with paint. Though not in use as a train table anymore, it is still flat and square, even though the basement is subject to wide humidity swings. Your mileage may vary.
I cut my subroadbed from 1/2" plywood about 2.5" to 3" wide for single track. No way would 1/4" work with that.
Mark
My ‘work in progress’ layout pretty much fills a double garage, roughly 18 x 20. The benchwork is your basic dogbone, rolled in on itself to form something like a double - G. The freestanding (almost) part of the structure is steel ‘C acts like L’ girder, with joists on 16± inch centers. Risers are also steel stud material, sculpted as necessary with tin snips and bending pliers.
I use thin (1/4 to 3/8 inch - varies depending on source) plywood cookie-cut subgrade, and control its tendency to deform by screwing steel angle stock to the underside where necessary. Atop that is a thin layer of foam (fan-fold underlayment) substituting for the cork or other material roadbed that I don’t use. The plywood serves primarily as an anchorage for screws - up from the risers (classic Westcott construction) or screw eyes for point actuator cable guides.
The plywood I’m using now has had a couple of years to adjust to conditions in my layout space, so it has pretty well sorted out any tendency to deform. (Or maybe it’s been scared by the pile of angle iron…) I have risers on 16 inch (or less) centers, and haven’t encountered any problems that exceeded the ‘minor nuisance during construction’ level.
Chuck (Modeling Central Japan in September, 1964)
Stay with 1/2" plywood, because 1/4" is noisy as a drum head [unless you laminate foam to it]. And it’s hard to screw Tortoise machines into 3/8" ply and keep them in place, so I would expect it to be even harder in 1/4". I used 1"x3" oak for framing on top of L-girders with 1/2" ply – I have used 3/8" Baltic Birch ply on previous layouts and it was stable, but all the plies are birch hardwood. It was noisier than the 1/2" I’m using this time.
Hi, I suppose I may be a bit late in the discussion, but don’t entirely toss the idea of using 1/4" plywood… But consider gluing 2 layers of it together, in effect making the equivalent of 1/2" (use lotsa clamps!). It is likely a tad more expensive, but the thinner material is easier to handle and cut. Use good quality stuff! If you stagger the joints by 6" or more, there is no problem with steps at the joints. Also, by cutting many pieces that are 3 to 8ft long, you can nest the cuttings on the original board and reduce wastage.
An added bonus is in creating the vertical transitions. If you cut the bottom piece(s), and set them in place on your supports, with the desired transition from level to the grade, then glue on the top layer, the inherent flexibility of the thin wood will give a pretty good transition, without cusps or vee-notching. Bending 1/2" plywood is a major pain.
I’ve used this method to create a 11x14’ cookie-cutter layout that crosses over itself, and is 3 levels deep in 1 place. I’d do it again.
Have fun, George
I use 1/4" plywood… under 2 layers of 2" extruded foam.
1/4" plywood I would never use by itself. Also as mentioned 2x4’s for the framework is WAY overkill. I use 1x4’s for the side rails with 1x3’s for the crosspieces and I still think I could get away with 1x3’s and 1x2’s and still be plenty strong, especially after the plywood and foam is glued on.
I build my boxes nominally to 2x4 foot sections, but if it will fit I keep the foam in one 8 foot piece (2 of the sections) since I’ve already moved one and find that a 2x8 foot section is no trouble to get out the door - and my layout is on the third floor. If I REALLY have to I can saw throught he foam and unbolt the pieces into 2x4 foot sections, but the fewer joints the better. 2x8 with the plywood and foam isn’t that heavy and it’s plenty sturdy. The legs and crossbraces bolt on for easy removal.
–Randy
I would ditch the 2X4’s anyway, paid or not, recyclable or not. I would use ripped 1X4 clear spruce or pine that has withstood at least a week in the basement/intended space without warping. You’ll lighten things amazingly.
Secondly, I would use 1/4", but if you are now feeling squeamish, I would try 3/8" ply. But, as suggested above, used as a base for 1" extruded foam, it would be great!! Try for supporting members below it every 12", on centers, and you should be fine.
-Crandell
Rich,
First off I agree with your 2x4 bench work I am of the school of thought it can never be too strong. I have seen several layouts where 2x4 construction comes i handy as the layout builders actually get on the layout to get to hard to reach places.That being said if you screwed and glued 1/4" ply to the bench work providing your support pieces are close enough together it may be marginally strong enough but with 1/4" it has enough flexibility that it will resonate sound liek a drum head. I use 3/4" as subroadbed in some places and for yard panels and some times I feel it’s a little overkill but like I said earlier it can never be too strong
Rich have you explored spline on an open 1" x 4" open grid. That would be a real money saver. You could then use plywood ( heavier than 1/4" I would suggest ) in yard areas and fill in the landscape with cardboard strips and goop.
Here is a photo of my spline on 1" x 4" open grid. It is elevated in this photo as it is winding its way into the Rocky Mountains. If the layout was to be flat, just lay the spline right on the grid. The nice thing about spline is the transitions up and down and left and right are easy to do as the spline finds the natural easements almost by itself.
Brent
Instead of reusing the 2x4s for benchwork, why not rip it in half and use it for legs?
Man, isn’t that the truth. I have had to rework some of the supporting members of the framework to make space for the Tortoises. Not fun!
That’s something that I haven’t even thought about, trying to mount Tortoises on 1/4" plywood, probably too thin to hold the screws firmly in place.