I have used luan plywood for shadow decoys for hunting ducks and geese during snow storms. Snow will build up on solid body decoys, and cause the waterfowl to flare out of range as a live bird will not allow snow to build up on their backs. The ones that I use are over 20 years old, and were painted with flat, exterior grade latex paint. I made sure to coat the edges with the paint, as well as the flat surfaces. (shadow decoys are just the outline of the bird, placed on edge in a lath 3/4 X 1 1/4 wide, 30 inches long--with a slot cut in the 3/4 wide demension, the decoy is placed in the slot, and fastened with two copper nails to hold it in place--they are in a Y configuration to float upright.) as long as the luan is painted all over you should not have any problems with warping/separation.
herrinchoker
billslake As said by others, I don't think sealing is necessary unless you get high humidity changes. If so, I would not use Thompson's . . . I'd use polyurethane, unless you are doing it in an enclosed area . . . then just use a cheap latex paint.
As said by others, I don't think sealing is necessary unless you get high humidity changes. If so, I would not use Thompson's . . . I'd use polyurethane, unless you are doing it in an enclosed area . . . then just use a cheap latex paint.
Seconded. There are lots of products out there to seal plywood that work yards better than Thompsons. Entry-level exterior latex will do a better job for less money; use polyurethane if you're willing to spend a bit more for top-notch results.
Stu
Streamlined steam, oh, what a dream!!
I used luan plywood as roadbed (in place of cork) in a couple of places on my layout, and not the exterior type. I had no problems with it de-laminating when ballasting, and I use a lot of wet water and a lot of diluted white glue for ballasting, too.
Wayne
WCU thanks, I remebered some discussion we had about nails and spikes into plywood. I did not realize Luan is softer.
Henry
COB Potomac & Northern
Shenandoah Valley
Big Daddy,
I was a fan of Jack Parker, the former owner of Central Valley Model Works. He passed away a few years ago. He strongly suggested using luan plywood because one could place spikes into it easily. Laun holds nails or spikes much better than Homasote.
Well if it is exterior Luan ply...no sealer is necessary..it is glued with waterproof glue. The interior grade may be sealed with a latex flat paint or solvent flat paint..but I really do not see the need, unless You live in a high/low humid area, with intense temp. swings. Use of ballast glue etc. should not affect it. Hollow core doors are made with Luan ply. My layout started in 1980, with the use of cookie cutter method...1/2 exterior ply on top of 1x3's that I ripped myself, over that is 1/2 inch Homasote, with flat Automotive primer, brushed on...different colors for different area's.....roadbed is same...Homasote. My layout is in My attic...first ten yrs. attic was not temp. controlled, It has been since then and absolutely nothing has warped/swelled or any other problems to any of the benchwork in all that time...in 36yrs. A lot depends on what the climate is on where You live...I live in the Mid-west, so I get all four seasons. Your choice of 3/4 plus 1/4 luan, in My opinion, is way overkill... but that's another story.
Some info about Luan Plywood:
http://homeguides.sfgate.com/luan-wood-99466.html
I have two large rooms in My house that I used 1/4 exterior Luan Ply as an underlayment....again no problems in 36yrs. I used ring nails to fasten it down....No squeaks!
Good Luck!
Frank
My understanding is this product is solvents and parrafin wax
I would say polyurethane is a better choice and unreactive to other scenery components.
Is 1/4" luan spike friendly?
I am using 3/4 inch birch plywood for my subroadbed with an additional 1/4 inch piece of luan plywood on top for convenience of spikes. Have any of you who are more expert than me in model railroading, ever sealed a layer of luan plywood to resist any warping with something like Thompson's Water Sealer. If one does use Thompson water sealant to seal the luan plywood, would their be any usual chemical reaction between the Thompson Water sealant and products like matte medium or white glue used when applying scenery to one's layout. I appreciate any and all assistance with making the decision or not to use the Thompson water sealant as a sealant with the luan plywood.