I'm looking for feedback on my process of creating exterior teak slab doors.
- Laminate core using (2) sheets of 11-ply Baltic birch with West Systems/Unibond 800. Vacuum press.
- Edge-band with 3/4" solid teak. West Systems/Unibond 800.
- Face veneer with re-sawn 1/4" thick, 6" wide straight grain teak with rasped edge detail.
- Seal with (2) complete coats of West Systems 207h, 105r. top coat with high content of UV protector marine varnish.
This seems like it should create a very sealed, stable exterior grade plank-like door, but any feedback is appreciated (i.e. core construction, glue choice, finish).
(Architectural Woodworking Forum)
You're going to need a press to lay up the 1/4 veneer on the plywood. Watch that the glue is compatible with the oily teak. You might want to wash the teak down with thinners before gluing. Remember that if you veneer the outside, you'll have to do the same on the inside.
We do this only as a 3 ply affair, usually 2-1/4" to 3" thick. The center core is a full mortise and tenon empty frame - no panels - with lots of cross rails (every 6"-8" or so, but only 2-3" wide). Long accurate tenons (haunched at either end) and very flat, 3/4 min. to 1-1/4 thick. Then make t&g faces for each side. We fill the empty panels with rigid insulation. Pin or tape the faces on each side (leaving expansion room at the joints), and glue (epoxy if teak) and slide into the bag. No need to edge band if you use the real thing throughout.
Regarding the jambs, we rabbet the sides onto a solid canted sill and the head, glue and lag. Then fit the door and swing, then latch.
I found this method is what works on lots of 50-75 year old doors here in the Midwest. They are still up and looking good, yet all the plywood and skinned doors, veneered doors, and others all are falling apart rapidly.
I would stay away from commercial cores (no ext. glue) and plywoods. I have learned to trust good solid wood and good solid craftsmanship. I think the epoxy finish is overkill unless you are fronting the North Atlantic - what happens if someone has to trim an edge? We see great results with a Sikkens system. And yes, this will be heavy. Eat your Wheaties.
The two elements of the door (t&g and core) have two distinct functions and work differently from each other. Just as in frame and panel where the frame does the work and keeps things on size while the panels just fill holes and keep out the rain and raccoons, the core needs heft to carry all the weight of the faces. This "beef" is accomplished by three strategies: 1. as thick as possible/practical, 2. 40% or so of the height is filled with horizontal rails, and 3. the rails have long tenons (2-1/2" to 3-1/2") to yield lots of surface area for glue as well as racking strength.
One thumb rule to keep handy is that the tenon should be approximately 1/3 the thickness of the stile with the mortise.
These doors are nice because you can add some vertical rails in the core and make openings for windows or speakeasies by adding rabbetted stops to the opening perimeter. We have even done a couple on radius to fit into curved walls - one with an arched head.
This can be done without a press, with cauls and clamps, but is a lot to handle. Must be done on a leveled bench or supports to start/stay flat whether a clamp up or vacuum bag.
I'm working on the outline for the book.