OSB VS Plywood

would personally not use homasote, its messy and dirty, the pink foam builder sheets are a better alternative, and you can layer them and contour them to your layout.  as far as the wood, I don't have a preference, but Plywood is the better route in my mind, I used 3/4" plywood on  mine, I can walk on it to get where I want to be

I also put my layout on wheels to move it around and off walls.

To each their own but I disagree on homasote.

#1 I find it superior at sound dampening.

#2 It's not crushable like foam.

#3 If you cut using a sharp knife, there is no mess or dust.

The reason I say this, our local club used 1 inch thick foam. It is a nightmare to work with later. If you have to lean on the layout or set anything down you get dents. Nothing actually sticks to foam long term, so anything glued or painted- scenery is always coming up and rips up the paint and glue. It's not any quieter for using thicker foam, and a lot more pain long term. I've got 80x9 feet I have to deal with and want to throw something whenever it involves mounting something or changes, even repairs.

At home I used homasote with felt on top nd by far, this is the quietest table top I know of.

Again, sorry to disagree, but if I had my way, never, ever, foam again, and definitely not thick foam like 1 inch.

I agree with Vernon. I have built two layouts with homasote, it is good stuff and can be cut and trimmed with minimal dust.

Re OSB, foggetaboutit and go for good plywood. Depending on the benchwork, 1/2 inch plywood with as many plies as you can find is usually sufficient. Spend the money to get good plywood.

Also, need to mention the burn marks in our foam from stray soldering  irons, wires burning up, anything that ever gets hot (even accidentally). Recently someone wired up a buble tube water tower to track lockon. look us a week or two, we kept smelling burning but intermittently. It was on a siding that was not powered all the time and when running command got full 18V melting the water tower base and light bulb into the foam.

Or there was that almost fire story of Atlas switch motors melting into foam in that one post. https://ogrforum.ogaugerr.com/topic/12129987998543558

Sorry, I know people use it and like it (foam) and it's light, easily accessible, relatively cheap. I understand why people like it, I just want to point out the known problems there can be on the other side of the story.

I'm not trying to cause panic paint foam as some huge risk. Just I have had my own bad experiences and completely opposite good experience with the alternative like Homasote. I also do understand the dust if you use a saw. Just don't use a saw, and cut with a really sharp knife by scoring it a few times and way less mess. Again, if mess is your concern, I understand, but here are ways. Again, I have some experience with both and never again foam as a base. Mountain or scenery OK, but not for my main table plan.

Homasote or Faced Sound Board over 1/2" or 15/32" plywood.  Most like Baltic or Birch... CDX (Plugged/Sanded) on one side is absolutely fine as well.

@Vernon Barry posted:

Also, need to mention the burn marks in our foam from stray soldering  irons, wires burning up, anything that ever gets hot (even accidentally). Recently someone wired up a buble tube water tower to track lockon. look us a week or two, we kept smelling burning but intermittently. It was on a siding that was not powered all the time and when running command got full 18V melting the water tower base and light bulb into the foam.

Or there was that almost fire story of Atlas switch motors melting into foam in that one post.

Soldering irons, wiring problems ,defective switch motors, overvoltage to an accessory.... It sounds like the foam is the least of your issues.

I've had good experience with homasote over plywood as well.

@RickO posted:

Soldering irons, wiring problems ,defective switch motors, overvoltage to an accessory.... It sounds like the foam is the least of your issues.

A couple of "harmless" flakes working together can cause an avalanche of destruction.

I would not use the Atlas rail joiner feeders as a main, primary or only supply.  Rail joiners may not provide a reliable electrical connection.

Nothing beats a properly soldered connection direct on to the rail.

The light wire on the Atlas joiner is OK for a short feeder.  Your  main buss or star supply should be in the 12 to 16 gauge range depending on length required.

With regard to the plywood versus OSB  debate,  look at new home construction.  Almost every new house has OSB  for floors, With joists set at 16 inch centers.  If you can put a 300 pound refrigerator with another 200 pounds of food and ice or an 125 pound washing machine holding 150+ pounds of water with no deviation from level,  then overpriced plywood is not necessary.

I am close to 300 pds  and used 1/2 inch OSB on a 2x4 frame covered with Homasote and been great on two layouts the first was up for almost 20 years and I recycled that OSB to my current layout now.

I used 18 gauge stranded wire which is more flexible and malleable than solid wire, and it won’t split or sever. It is often used for indoor applications such as electronic devices, circuit boards, and speaker wires.  My layout is 15 X 6 Ft.  You may want to use 16 gauge is you layout is larger.

@RickO posted:

The lighter weight of osb makes it easier to work with.

Actually OSB is heavier than plywood, but not by much.

John

@third rail posted:

With regard to the plywood versus OSB  debate,  look at new home construction.  Almost every new house has OSB  for floors, With joists set at 16 inch centers.  If you can put a 300 pound refrigerator with another 200 pounds of food and ice or an 125 pound washing machine holding 150+ pounds of water with no deviation from level,  then overpriced plywood is not necessary.

Builders use OSB because it's cheap.  Period.

You couldn't pay me to use OSB on a train layout.

I didn't even consider OSB when I built, and I wouldn't now, even though it's cheap.

there is a reason why OSB is cheaper than real plywood....and it's not b/c it's better.   

Whenever this topic comes up, it generates strong opinions, so here's mine.

If you're putting another layer of something (foam or homasote) on top of it, OSB decking is fully sufficient - as others have noted, it will support roofers (and snow loads), so it will easily handle toy trains.  3/4" plywood is usually overkill and a needless expense.  If one isn't using foam or homasote, then go with 1/2" plywood.

I've used both homasote and foam.  Homasote really sucks up the paint, deadens sound more than foam, and will hold the track in place with nails or screws; foam is light and easy to work with, but the track needs to be glued down.  IMO, comes down to personal preference.  Next time around, I'm thinking of going with 1/2" plywood and cork roadbed - no homasote, and I'll use foam for land forms.

some people don't like OSB b/c of all of the cr*p that's it made from.  others don't like to have to inhale said cr*p when you cut, sand, plane OSB.

FWIW, most of the layout builders who have a furniture making background....myself included....use baltic birch.

i use regular plywood for lots of jobs.  i never use OSB for anything unless i have no other option.  i straight up hate it.

it's still a Free Country and not everyone has to agree. 

I don't even have a furniture making background and I used baltic birch.   It was really nice wood to work with, and truly rigid, no warping with that stuff!