What plywood to use?

[Kickout]

When building HO grades what plywood thickness do you use? Willl 3/8” work?

 

[ctclibby]

Kickout: You know you would get the 'It Depends' quip. 3/8 by itself probably will work with 12" joist centers If you are doing a single track rise, it is not very wide which takes away from the overall stiffness. Double track+ better. Are you putting something on top besides cork/whatever roadbed? IE.. sandwich it with something? From what I have seen and tested, 1" blue board on top, ply on bottom and you come up with something pretty stiff. If you are concerned about spiking the track into blue board, no biggie, put the ply on top. Just need to make sure you have a very good glue setup with no air bubbles in between.

L8r

 

[Old 97]

 

[timlange3]

Depends on the weight you want to put on it and the width. If your doing N scale the supports every 12" should be enough, if you are doing O scale then 6". Cut a test piece a couple feet long and put the expected weight on it. If the center of the board deflects bring the supports closer together.

 

[RhB Michael]

I used 1/2". I would not have used anything lighter whether it was a single track or double track.

Use 3/8" and your support spacing is going to be closer with better odds of a table crossmember not located where you need it. More work, more wood.

Also a better chance of dimensional instability if you do not seal all of the edges.

 

[John from Indiana]

I used 0.5 inch good on one side

 

[rgeiter]

I’m using 1/2 “ as well.

 

[bnsf971]

If you want it to never move, use 1/2".
If you want to be able to change the grade slightly, use 3/8"
If you want to be able to easily change grade over a shorter distance, use 1/4"
The thinner the base, the more support will be needed to keep things where you want them.

 

[Marlin39]

If you want it to never move, use 1/2".
If you want to be able to change the grade slightly, use 3/8"
If you want to be able to easily change grade over a shorter distance, use 1/4"
The thinner the base, the more support will be needed to keep things where you want them.

This is exactly it. I use 1/4" ply with 1/4" cork sheet on top. Cork holds track nails better than foam since you're pushing it slightly into the plywood.

 

[Selector]

5/8" is very stiff, and it holds up very well across 3' spans with the typical loads found in HO. Otherwise, I tend to use 0.5" G1S, and here the supports below it run about 20" tops.

 

[riogrande5761]

I don't use Plywood. So much of it is warped at the lumber section. I use OSB 23/32
which is between half inch and 3/4 inch. I would suggest minimum of 1/2 inches but for narrow section that are 1 or 2 tracks wide, thicker is better.

By way of example:

 

[AstroKnight187]

When building HO grades what plywood thickness do you use? Willl 3/8” work?

Standard half inch thick plywood is all you really need, and then you can use Woodland scenics riser starters to meet it, or maybe homesote if it works better for you

 

[Canalligator]

I tried half inch OSB, but I didn’t like the irregular surface. It was difficult to mark with a pencil, and tricky to start a drill exactly where you needed (such as mounting switch machines or drilling for feeders). I think a sheet of plywood is worth spending a few dollars more for.