Replies

1. 
   Jim_Allen | Apr 23, 2008 02:37am | #1

   If you seal all six edges of the plys, you probably would mitigate any warpage.

   Bob's next test date: 12/10/07

1. 
   keith_n | Apr 25, 2008 06:32am | #2

   Just bumping to see if I get any other thoughts before I go to the lumber yard tomorrow and buy 26 sheets of ply. The lumber yard suggested 3/8" luan for the outside of the doors and 1/4" luan for the interior. I know nothing of this plywood. Googling it seems to indicate use mostly as an interior door application. I intend to prime all sides and edges of whatever I use. Any thoughts regarding normal ply versus luan? Remembering that this is a shed, I hate to spend money for ply that doesn't need to be spent but I also want it to last and to look nice. A previous thread led to some posts suggesting 1/2 or even 5/8". Comments?

1. 
   sapwood | Apr 25, 2008 06:51pm | #3

   Maybe you've already gone to get supplies.... if so, sorry I'm late.I don't get why you want to use a steel frame on the perimeter. It adds virtually no strength and makes the construction problamatic. What you are proposing is a real hollow core door. It has no stiffening members internal at all. You will get some warpage both interior and exterior. I suggest you investigate making a torsion box door. These can be made several ways. The usual is an internal core of inexpensive stock that is simply butt joined and stapled together. The strength comes from gluing the outer skins of plywood to every internal surface they come in contact with. This results in a very stable, lightweight, and strong panel. You will not need the steel although I can see where it may aid in bumping abuse. A torsion box door like this requires a very flat surface on which to build it because any twist will be permanently built into it. You can use 1/4" ply on both interior and exterior with no problem. Use waterproof glue.

1. 
   bill_mcgonigle | Apr 25, 2008 07:19pm | #5

   The usual is an internal core of inexpensive stock that is simply butt joined and stapled together.

   What type of materials are commonly used for the core? Pine? Foam?

1. 
   sapwood | Apr 25, 2008 08:41pm | #6

   The core can be any stable wood of your choosing. I've used pine, fir, philipine mahogany, and even plywood. Usually 1x material is used although it doesn't matter. Ease of construction usually dictates. I've also used blue styrofoam for the core with polyurethane glue to attach the skins. I have and use a vacuum press, so this process is pretty easy with foam. Vacupress (http://www.vacupress.com) sells a honeycomb material for the core. I've never used it because the cost of shipping to me is prohibitive. I've found the foam to work very well. There was an article in Fine Woodworking many years ago that is considered to be the primer on the topic. It may be online at FWW, but if not I'll scan it and email you a copy if you want.

2. 
   bill_mcgonigle | Apr 25, 2008 08:50pm | #7

   There was an article in Fine Woodworking many years ago that is considered to be the primer on the topic. It may be online at FWW, but if not I'll scan it and email you a copy if you want.

   Thanks, I'll check my stacks. :)

   Edited 4/25/2008 1:51 pm ET by bill_mcgonigle

2. 
   Jim_Allen | Apr 25, 2008 07:12pm | #4

   Dont let them talk you into anything that does not have exterior glue in the manufacturing process. Bob's next test date: 12/10/07

2. 
   Aaron | Apr 25, 2008 10:10pm | #8

   This may be too late, but if you are still in the planning phase, this may give you some ideas:

   http://www.armourgates.com/super-structure.html

   It looks like you just use 2X material to fill in the door.  I think I would create a shiplap so that it is more weather-tight.

1. 
   bill_mcgonigle | Apr 25, 2008 11:24pm | #9

   Double doors... *smacks head*Thanks, this post just solved one of my outstanding design problems, I'm embarrassed to say.