How wide do I make the plywood on a grade?

[SpaceMouse]

I'm going to be using Atlas 100 track, split cork bedding. How wide Do I make the plywood and how thick should it be. I have a bunch of both 3/8 and 1/4. Do I need anything between the bedding and the ply?

[rrinker]

Both are probably too thin, unless you provide a lot of support. If you install frequent supports (every 6" or so) it won't sag.
Width, well, it only has to be slightly wider than the cork. If there will be any lineisde structures along the grade, you need a wider space for that. All you need is support for the track and a place to attach scenery formers of some sort to.
Yuo don't need anything between the plywood and cork.

--Randy

[johncolley]

Glue the 2 together with liquid nails that will give you 5/8" Anythig between 1/2" to 3/4" is good. 3" wide for single track, 5" or so for double track.

[Anonymous]

Make it as wide as you'll need for roadbed and any trackside scenery. Glue the cork to the plywood.

Both thicknesses wil be ok, with support every 12 to 16". There is almost no weight bearing on it and I assume you don't subject it to monsoon rains. If there is a sag, I think you will need scientific instruments to measure it. You probably will also be adding attaching scenery to it which will provide additional support.

Since there is hardly much more work or cost involved, place your supports as close as makes you feel secure.

Wayne

[SpaceMouse]

Just playing with my caluclator, I noticed that if I have a 4% grade in 4x8 layout with approximately 6' of grade, my track will be off .012 inches or about an 1/8" when I reconnect. I assume that is well within the fudge factor. (I haven't even considered flex for an 18" radius.)

Also my I don't have trig functions on my calculator. What angle would I cut the top of my supports on 4% grade if I were anal enough to care?

It's a slow day here in the store. [:)]

[rrinker]

12 thousandths of an inch over 72 inches? That's meaningless. It would only be a tiny gap if all in once place - but you can space the difference out over the entire 6' run and it will TRULY not be noticeable.

As for the angle, it's about 2.3 degrees. Just cut them off square.

--Randy

[SpaceMouse]

QUOTE: Originally posted by rrinker

12 thousandths of an inch over 72 inches? That's meaningless. It would only be a tiny gap if all in once place - but you can space the difference out over the entire 6' run and it will TRULY not be noticeable.

As for the angle, it's about 2.3 degrees. Just cut them off square.

--Randy

Oops. You're right. Not 1/8. Read the decimal wrong. 2.3 is not worth doing. Told you it was a slow day.

[rrinker]

Even if you missed it the wrong way, and it IS .12, spread out over the length of the 6' run it's STILL meaningless, so you're safe either way. I'm fussy, but I'm not insane [:D] although some may argue that point/.

--Randy

[dave9999]

Spacemouse,
You do realize that 4% is a pretty steep grade? Just checking. Dave

[SpaceMouse]

QUOTE: Originally posted by dave9999

Spacemouse,
You do realize that 4% is a pretty steep grade? Just checking. Dave

Yes, I do. The only place I'm using a 4% grade is on a 4x8 layout. There will be three trains running: The Hogwarts with two cars. A 4-4-0 with 3 Overton passenger cars and a 2-6-0 with 3 30' cars and a caboose. This will be used only until the bigger track is functioning.

The Hogwarts makes it up with a little extra juice--doesn't seem to be straining too hard. Is there a significant increase in wear with constant 4% inclines. My kid really likes the bridge.

[cwclark]

I keep my plywood the same width on the entire layout ...I use 3/4" plywood at 2 1/4" wide...I "cookie cut " it out of a sheet of plywood and place it on cleats and risers...here is a picture of a 3/4" cut plywood starting an incline http://community.webshots.com/photo/137793353/163233393cqfzCl there are more pictures if you click the arrows to the left or right ....chuck

[SpaceMouse]

QUOTE: Originally posted by cwclark

I keep my plywood the same width on the entire layout ...I use 3/4" plywood at 2 1/4" wide...I "cookie cut " it out of a sheet of plywood and place it on cleats and risers...here is a picture of a 3/4" cut plywood starting an incline http://community.webshots.com/photo/137793353/163233393cqfzCl there are more pictures if you click the arrows to the left or right ....chuck

Believe me when I say I know I'm a novice, but don' t you think that 3/4 ply supported every two feet is overkill? You could walk on that without it sagging.

Seriously, I build my workbench out of 3/4 Ply with supports every 2 feet and I have my 14" miter saw, drill press and mechanics tool chest on it.

[cwclark]

over the years, I've built just about every type of benchwork and used just about every type of plywood for sub roadbed there is and have found that the 3/4" is the best...I've used 1/2" and 3/8" before and after a few years it began to sag...this is my last layout i'm building now, and i want it to be as sturdy as possible with no sags over the next thirty years (The good Lord willing that I get to live that much longer)...I don't think it is overkill at all....there is nothing worse than spending hours laying track to have problems later with plywood that sags....i'm almost 50 years old and over the years i've found that if you want it to last a long time, build it as sturdy as possible...another thing... the 3/4" plywood makes a very well defined roadbed after the scenery is added...chuck

[SpaceMouse]

Like always, I'm getting plenty to think about.

[beyerswede]

Greetings from the land that invented plywood. I also use 3/4" for major workbenches and in this state have never had one iota of problems with 1/2" although I do say I support it every foot.

[Anonymous]

I got about 5 sheets of 3/4" for free, and also some 3/8" as well. I plan to use the 3/4" all over and then use up the 3/8" doubled to finish if i don't make it with the 3/4".

[SilverSpike]

A big thank you to cwclark for sharing the webshot photos of your layout construction process. Great backdrop clouds!

Thanks!

Ryan

[Jetrock]

SpaceMouse: Have you considered doing your grades with Woodland Scenics foam roadbed? You can get pre-made grades of 1 to 4 percent, and there is less fiddling around with a jig saw...you can just make a nice solid flat table and mount foam on top of it.

[SpaceMouse]

QUOTE: Originally posted by Jetrock

SpaceMouse: Have you considered doing your grades with Woodland Scenics foam roadbed? You can get pre-made grades of 1 to 4 percent, and there is less fiddling around with a jig saw...you can just make a nice solid flat table and mount foam on top of it.

I have considered it, but the two skills I do have are woodworking (contractor 15 years in your state) and math. Still factor in the cost of the plywood and...