The New Northern Central

[Ed Kapuscinski]

Any plan for foam or other material to allow for below ROW height scenery?

Yes, but there won't be MUCH needed since everything in these areas is pretty flat and much is covered in track. I figure areas where there isn't track and where I might want some space I'll just bust out the jig saw and poke through. In these areas I imagine that'll be pretty minimal though. The rest of the layout, on the other hand... well, I've got other plans there.

[MK]

The concern is not weight, but warpage.  Plywood curls, too.  A lot also depends on how far apart Ed is placing the shelf brackets.  Now, if he's gluing 2" foam to the top of the plywood, then what he's got is likely more than sufficient.

DFF

I agree.  Depending on the wood's quality at this thinness you might have the "hippty hops", horizontal scalloping like a suspension bridge's cables but at a much lesser degree.

What about MDF, do they make it less than 3/4"?

[Steveruger45]

Ed, what you are suggesting is how I would think to do it too. That said I tend to over-engineer everything.
 However, depending on sub structure framing and spacing of support brackets Have you or anyone considered using or have used 7/16” OSB with 3/4” foam on top for the base layer?

[nickelplate759]

Ed, what you are suggesting is how I would think to do it too. That said I tend to over-engineer everything.
 However, depending on sub structure framing and spacing of support brackets Have you or anyone considered using or have used 7/16” OSB with 3/4” foam on top for the base layer?

MDF is super heavy, and can sag worse than plywood - don't use that.   My one concern is that you the only thing keeping the plywood from sagging between supports is your Masonite front fascia.   That  should be enough, but if you omit it for some reason then you might have a problem.  You might also have a sagging problem at the back edge.     I'd consider running 1x2 (nominal) along the back edge, between the 1x3 supports.

[wazzou]

My assumption @Ed Kapuscinski is that where you show the 1x3 dimensional lumber, that is a box, correct? 
Front and back and girders on the brackets?

That is the way I would do it if employing your technique.

[davefoxx]

True, but if he stays on 16 inch centers for his supports he should be fine. Going to 3/4 adds a lot of weight.

Agreed, but let's hope that Ed doesn't try to save weight by going to CDX plywood. 

DFF

[Steveruger45]

My assumption @Ed Kapuscinski is that where you show the 1x3 dimensional lumber, that is a box, correct? 
Front and back and girders on the brackets?

That is the way I would do it if employing your technique.

Yep, me too.  I just assumed the 1x3 transverse bracing would be matched with longitudinals too.  But right enough that isn’t shown on the sketch.

[Pomperaugrr]

"P.S. I'm still loving the Barrina LED lights.  Thanks for the heads-up on those!"

All credit is due to @DeltaBravo . He turned me onto them. I just kicked the hype machine into full speed.

I second the thanks to all involved.  I took out the 10 shop lights I was using and put in Barrina LED lights thanks to the recommendations here.  What a huge difference in appearance and in heat generation.

Eric

[C855B]

MDF is super heavy, and can sag worse than plywood - don't use that. ...

And is especially vulnerable to humidity.

[amato1969]

However, depending on sub structure framing and spacing of support brackets Have you or anyone considered using or have used 7/16” OSB with 3/4” foam on top for the base layer?

I agree that 3/4" ply or OSB is heavy and probably overkill.  What about a "sandwich" of 2" foam with thin plywood as the "bread"?

Downside could be eating up clearance between upper and lower levels though 

  Frank

[davefoxx]

My assumption @Ed Kapuscinski is that where you show the 1x3 dimensional lumber, that is a box, correct? 
Front and back and girders on the brackets?

That is the way I would do it if employing your technique.

I don't know, Bryan.  That might be overengineered, which isn't necessarily a bad thing.  But, I agree with @DeltaBravo that if Ed goes no more than 16" between shelf brackets, then he'll be fine without boxing those 1"x3" members.  At 16" o.c. and 1"x3" joists, there's only going to be about 13-1/2" unsupported between the brackets. I doubt 5/8" would sag that much in that span.

DFF

[Ed Kapuscinski]

Oh yeah, MDF for fascia and backdrop use only.

I wasn't planning on doing girders, just a 1x3 laying horizontally.

I thought about going with stringers along the front, but hadn't thought about the back. Either way, I'm not really that concerned about sag in the ~14" that will actually be between the supports. If I were going further between brackets I might consider some stringers to give it some more anti-curl support.

I'm not planning on putting foam on top because I don't think it'll be needed in these spaces. Again, this is really only under tracked areas.  The lack of foam is two-fold. One to cut down on vertical height between decks, and two to make mounting under-track hardware (like slide switches) easy.

[nickelplate759]

The Masonite fascia will do just fine in place of a front girder if you screw it into the plywood deck - or even if you glue and nail it.   It won't help at all if you only attach it to your 1x3 beams.

[Ed Kapuscinski]

The Masonite fascia will do just fine in place of a front girder if you screw it into the plywood deck - or even if you glue and nail it.   It won't help at all if you only attach it to your 1x3 beams.

Haha, that makes enough sense that I almost forgot about it. Thank you for reminding me.

[conrail98]

Oh yeah, MDF for fascia and backdrop use only.

I wasn't planning on doing girders, just a 1x3 laying horizontally.

I thought about going with stringers along the front, but hadn't thought about the back. Either way, I'm not really that concerned about sag in the ~14" that will actually be between the supports. If I were going further between brackets I might consider some stringers to give it some more anti-curl support.

I'm not planning on putting foam on top because I don't think it'll be needed in these spaces. Again, this is really only under tracked areas.  The lack of foam is two-fold. One to cut down on vertical height between decks, and two to make mounting under-track hardware (like slide switches) easy.

I would do 1x3s across the holes between brackets. You've mentioned signaling and the like, you're going to need solid wood to mount those pieces to. If you run stringers between the brackets instead of just on them, you give yourself plenty of area to mount those items,

Phil