Hi everone, im new to the form and was looking to see if anyone else used OSB and if so how did it work out for them
My new layout is about 10x16 and its a combination of the 1/2 inch osb with 1inch and 2 inch foam glued on top depending on the scenery , the inclines and hidden track areas have no foam. The areas with foam are pretty solid but the other areas seam to have a little flex, they are cockie cut out of the osb and are about 3 inches wide and supported about every 16 inches. I was debating if i should replace them with plywood or reinforce them before i lay the track
I would predict that you’ll be very disappointed with the long term performance of OSB. Since it is made up of various small pieces of scrap wood laminated together into a sheet product, it does not have the uniform strength qualities of true plywood. It was designed for use as cheap shear paneling in wood framed structures. In other words, its strength is resisting compression and elongation movement across the face of the panel. It was never meant to support loads against the panel face (as in a floor or table top). The surfaces of OSB are not as smooth as plywood either.
You might get lucky and have OSB sheets that are relatively strong across the length of the sheet. However, it is more likely that the OSB you have has multiple hidden weak spots that won’t surface until after you have completed your benchwork. Such failures would likely result in “mystery” kinks in your trackwork that eventually get bad enough to derail trains. Moisture from scenery material application could also damage the OSB. Even cheap “big box” store plywood would be a better choice.
Your benchwork is the foundation of your model railroad. As with any foundation, it is not the place to save money!
I agree. OSB might look strong, but it isn’t. Pick up a 3" wide piece in your hand and give it a twist. It’ll crumble. And even with support at 16" centers, it’s likely to sag as well.
My layout is 10’ x 14’, I built my helix 28 years ago from 3½" wide ¼” OSB and I haven’t had any problems with it. I braced it every 12” with 1" x 2" furing strips and it’s glued and screwed.
Early on my garage (my layout area) wasn’t totally insulation and the garage would be well in to the hundreds in the summer. During winter the temperature would drop in to the low 30°s, a 70°+ temperature swing. I have since added R30 insulation and the temps now are between the upper 50°s to low 80°s. The OSB has remained the same as built 28 years ago.
Mel
Modeling the early to mid 1950s SP in HO scale since 1951
The OP was referring to 1/2", a huge difference with OSB.
And he was cutting it into 3" strips for the “cookie cutter” part. Sure, it will work, as Mel used it on his helix, but it needs extra support, especially if he is going to nail his track down.
I used 1/2" OSB on my garage walls, and 5/8" on the roof. No problems.
And as Randy states, it’s used as sub flooring, but usually in potential wet areas, like in front of entrance doors, kitchens, and bath rooms, in Wisconsin anyway, plywood is used.
When it gets wet, or just sits around for a while, unused, and unprotected, it expands.
Well, not always. My SIL owns a nice house with OSB flooring. The main floor has been fine, but the upper floor has had to be replaced. The main floor was covered with hardwood and ceramic tiles with subflooring. The second floor was carpet on OSB. Before they replaced the OSB I had to walk very carefully because the floor sagged significantly under my weight. It actually felt like the carpet was holding my weight rather than the OSB. Eventually somebody (not me) put their foot right through the floor.
As for using OSB for roofing, when I sold roofing I had to give a lot of people really bad news about their OSB roof. Under perfect circumstances it survived the Canadian climate. Under less than perfect conditions it would add 50% to the cost of the roof because of the deterioration of the original OSB.
My position is this: You are spending a lot of money to build your layout. Why take a chance on OSB when the price difference between OSB and decent plywood isn’t that huge. So you save maybe $200 by using OSB. Fat lot of good that will do you if your $4000+ layout starts to fall apart down the road. It sure as heck is going to cost you more than $200 to fix the problem. Never mind the time and frustration involved.
Why take the chance? You get what you pay for! I want to spend my time running trains, not fixing the layout.
I’ve used nominial 1/2 inch OSB on 3 layouts now and had no trouble with it. Many others have said the same. A few warn against it but I haven’t seen any actual cases where they said they had sagging for example, just that they say it will.
One thing I have noticed is that plywood is MUCH more expensive. If money is no object, then sure, buy high grade plywood. If you are on a budget, 1/2 inch OSB seems to do the job well.
At Home Depot, a 4/8 sheet of 19/32 BC plywood is $31.97. A 4/8 sheet of 19/32 OSB is $19.87. If your layout needed 3 sheets, that’s a whopping $36 difference. When a single 20 car train with 2 diesels can easily cost $1,000 or more, I find it hard to look at $36 as a big deal.
Thanks all for the suggestions, for me it was’nt about the cost I have about 10 sheets of the osb and a dozen sheets of the 2 in foam leftover from a job and figured if i could use some of it why not , but I got a piece of 5/8 finished ply from depot today and ripped a couple new 3 in strips out of it and can definitly notice a diffrence at that width
I read all of the reply’s and I found them interesting to say the least. BUT I just checked prices at Lowe’s and a 4x8 sheet of osb 7/16 is 15.25 and a 4x8 23/32 (3/8) sheet of plywood is 32.58. So at a 50% saving I would use the USB, I have done a lot of work for OSB in the past and it will support the weight of a tack just fine with 16" on center supports. What are you placing on top of it? 500 pounds of weight? The down side to OSB is that it does not like moisture. But I’m pretty sure we are not running our trains out in the rain or in the pool room. I will use 7/16 OSB with 2+ inches of foam board on top of that. Hell if I build a helix I’ll use just 2" foam board. It’s not like you will have a lot of weight on it at one time and it will be supported as necessary. If my helix was really wide, say 6+ inches then I’d use a different material but let’s be reasonable here folks.
Oh and by the way there is a glue side to OSB that is pretty water resistent as well.
