Have you used MDF?..........

[rockythegoat]

Anybody out there used 1/2 or 3/4 inch MDF with birch veneer both sides, for framework for your layout? Thinking of getting a 4x8 sheet, ripping to about 3 inches wide and using the 3-inchers for the frame. Frame will be covered by 2 inch blue/pink board.

Layout is planned to be 2 foot wide, around the walls, suspended by wall brackets, and located in an 11x13 bedroom, heated/air conditioned. Illinois humidity, though.

Wondering if the better plan would be to go with 1/2 or 3/4 veneer plywood.

Cost is the thought here. I'm also a slot car nut and a lot of the tables for the tracks (and the routed tracks) are made from MDF and appear to do fine.

[Anonymous]

I've used it for other stuff, and the main problem you have to worry about is warping along the length. Wood would do this less. Unless you were going to make a torsion box, which you'll have to google to find a picture, I think that a box would have warpage problems, unless you secured it to a horizontal panel to stabilize it. What you could do is use two 3" wide planks to make an L girder, and that would stabilize it along the length, but you would double the material and the weight.

As for plywood, you would still have this warping problem. It would require extra work time to account for the warping, such as edge banding with a 1" wide wood strip. This is just my opinion based upon woodworking experience with these materials.

I have been considering pallet wood, scavenged from thrown away pallets. Less warping in my opinion, but does not have a nice finished surface. You could cover the apron with 1/8" hardboard for a finished look.

John

[Anonymous]

I would have to dissagree with the comment that the veneer plywood would warp. This is probably one of the most stable wood products that you can get - providing that you get the good stuf. The MDF sill sag noticeably if not reinforced with either solid wood or high quality Plywood. It is also very much affected by moisture. My 4x8 layout sits on 5 four inch wide pieces of 3/4" ply running lengthwise, and has not warped or sagged in the 10 years since I originaly put it together.

[bogp40]

Leave the MDF for Trading Spaces- stick with the more stable quality plys.
Bob K.

[Anonymous]

Hello
other then trains i do alot of wood working and have used alot of different types of woods
i would have to disagree on MDF warping i have a layout with the top 3/4 mdf
makes it great for putting nails in it is not as strong as wood that has grain.
Mine is two years old and has no warping at all. I have a garage full of diffent ply wood and i have seen 1/4 ply warp before my 1/2 MDf when you get up in the thicker plys they have less warpage remember in order for wood to warp in has to have a grain in it.MDF has none but it will DEFORM if it get wet (soaked)
and it is not as strong as ply . use it wisely... building a bench out of it is not a good choice.

[Anonymous]

Cabinet grade plywood. High quality, no warp. I still like sticks for bechwork. Have used 3/4" ply ripped into 3" strips for some benchwork and didn't like it's lack of vertical shear strength (ie easy to bend along it's length on edge). Replaced it with 1x3 sticks....

Guy

[Anonymous]

I've been using 8mm MDF on my HO layout, and it's pretty good so long as you put decent framing on it. Having said that, I will probably use thinner MDF if I build another layout as it's very heavy, and a board I've built for a diorama using an offcut of 6mm MDF seems to be resistant to warping.

[rockythegoat]

Thanks all for your help!

I figured using MDF as a top was okay, but, using as a framing member was dicey.

I have used plywood in the past without any warping issues, although, I was using cross pieces on 16 inch centers.

Locally, based on getting (16) 8 foot pieces, out of 4x8 3/4 birch veneer plywood, it will cost me $2.25 per board. The cheapest stick board I can get, based on top quality wood, will be a 1x6 ripped, $5.00 each.

[CP5415]

I've only used MDF to make shelves in a pantry for my kitchen.
I prefer using wood. MDF is heavy compared to wood & not as nice to work with.

Gordon

[Anonymous]

I have extensively used both plywood and MDF in furniture building as well as hardwood lumber. MDF has its advantages and disadvantages. MDF is indeed very heavy, not as strong as plywood (more prone to sagging) and, a very negative point, generally contains considerable amounts of formaldehyde glue which can become a health concern in an airtight home. With barometric changes, MDF releases formaldehyde gas, a known neuro-toxin. Thermofused melamine panels with an MDF core can seal in these gases, particularly when the cut edges are all either banded (Melamine banding) or sealed with shellac or parrafin (paint doesn't seal). All considered, I would recommend that you stick to plywood. I built several plywood RR modules over 30 years ago and they are still in excellent condition today.

[Bikerdad]

There is one other aspect of using MDF that has not been mentioned: cutting and machining of MDF generates HUGE quantities of dust. It is generally not recommended for use as a structural member. It is dead flat and stable, and generally stays that way except for the sagging. It will sag on the order of particle board if unsupported.

I personally would not use it, but that's may in part be because I'm a 'wood snob'.

[Anonymous]

I work for a millwork distributer, MDF (medium density fiberboard) will sag and swell in higher humidity, I used OSB (oriented strand board) on a recycled wood frame, top covered with styrofoam and scrap trim from work to hide the recycled wood. The wood came from pallets and shipping braces, the OSB came from packaging on the pallets. My last one was set up for 8 years with no problems and am currently rebuilding with the same materials. The reason I am rebuilding is that I moved. My train room is heated and air conditioned, and has its own dehumidifier. It is located in the basement of a house that was built in 1856. The first phase was built 3 years ago, and no problems, this winter the next section will be built.