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gofish
11-22-2009, 04:47 PM
Guys, I'm asking for some advise please. Not a boat question but very close.
I need to finish a beautiful custom made exterior door. It is constructed of solid mahogany. 2 stiles and 2 rails with 1 large flat panel. The home owner was told the panel is 1 solid piece. The panel is aprox 28-29" wide. I can't find a glue line or any evidence of a joint on this panel. Is This possible??
My concern with finishing this door is the panel warping, cupping and wracking the door.
I intend to finish it bright with 3 coats of clear epoxy followed by 3-4 coats varnish. This was decided for both estetics and primarily minimize maintenance.
I am worried the epoxy will not allow the panel to "float" in the door. If I eliminate the epoxy and go with multiple coats varnish I'm sure this will have the same effect.
I don't want to use a penetrating oil as a finish as the home owner does not want the maintenance.
Are my worries warranted?

Ed

Jim Ledger
11-22-2009, 04:56 PM
Yup. It's possible that the panel is one piece. Doesn't matter, though. The panel probably won't warp the door, but it should be able to come and go. The door should have been designed with a center stile to reduce the panel width. Architects and designers are notorious for drawing foolish constructions like this one. That panel could easily move a quarter of an inch, leaving an unfinished strip showing next summer. It's common to have to go back and touch up panel doors after the panel shrinks. Varnish would probably be OK, but epoxy will glue the panel in place and probably cause a split.

Just one opinion. See what others have to offer.

Peerie Maa
11-22-2009, 05:02 PM
Why not coat the panel and the grooves before assembling the door? Then when you coat the rails and styles ensure that you do not let epoxy glue the panel in place.

Jim Ledger
11-22-2009, 05:18 PM
The way I read the post, the door is already made and that this is a finishing problem, otherwise, your advice would be right on.

Tom Robb
11-22-2009, 05:31 PM
This has little or nothing to do with epoxy in/on boats. It's cabnet making/finish carpentry. That panel must float or it will split.
If the panel were plywood rather than solid timber you could glue it in, otherwise seasonal moisture changes will ruin it - in an exterior door particularly.
If you could disasemble the door w/out wrecking it. finishing the panel before reasssembling the thing may hide the unfinished edge in winter dry season.
If the owner doesn't like maintenance, sell him a fiberglass fascimile door.

kc8pql
11-22-2009, 06:21 PM
If the owner doesn't like maintenance...
That will be the downfall. Panel movement will be the least of it's problems. I've never seen a homeowner, or designer for that matter, understand what it takes to keep up a bright finished exterior door.

john92021
11-22-2009, 06:29 PM
Hi Ed, Seeing you didn't make the door I would be very careful that it really floats enough before you accept responsibility for the door. I've had to repair too many that blew up. You could tape it so that no epoxy gets in the seam and do it in 2 sections. Sealing it with more than one coat of epoxy is going to make trouble for you in thickness. I would seal it inside and out and then do your normal varnish job. More disasters have been caused by trying to hard than from not trying hard enough. The panel will only get bigger from now till spring.
Good luck, John

MiddleAgesMan
11-22-2009, 06:49 PM
If that panel is solid wood, not veneer on ply, it's a disaster in the making no matter what you do with the finishing. Prefinishing the panel before assembly wouldn't help either, it would just delay the explosion or cracking by about....10 days max.

If the door is still in the raw wood stage there is one magic elixir that might save the day for the homeowner. Coat the entire door with Nelsonite Wood Stabilizer then finish it however you want.

David G
11-22-2009, 07:27 PM
MAM,

I've seen Nelsonite Wood Stabilizer on the shelf, I think, but never paid any attention to it. Is is Bentonite based? If it is, that might be a good idea. I agree that the epoxy is a non-starter... unless you can be so fastidious as to not not get a hint of it into the grooves. That's no big deal, though, cause the epoxy is not all that helpful in this situation. I'd just go with straight, good quality, spar varnish. You'll probably need more than 6-7 coats. Make sure the homeowner knows what you're putting on (and, therefore, what he needs to recoat with).

Ron Williamson
11-22-2009, 08:28 PM
I'd like to know climate/weather conditions.
If the door is exposed to the south with no porch roof,in an area with huge temp and humidity swings,then there is no hope.
R

gofish
11-23-2009, 12:25 AM
Thanks for the replies.
The panel is not veneer on ply-There are verticle v-groves routed in for detail.
The door will be hung western exposure w no overhang. Long Island, NY w lots humidity, temp, and sun exposure. No screen door so snow, rain sitting on the kickplate. Let's assume the neighboorhood dog will pee on it as well.
Didn't find much info on Nelsonite and probably wouldn't put faith in something I have no experience with and you guys aren't wholehearted behind.

The consensus sounds this door is bound for trouble. Do I hear this right?
The idea of sealing this door totally to avoid moisture intrusion is not well founded I assume?

Thanks
Ed

David G
11-23-2009, 01:35 AM
Ed,

I've been doing custom woodworking since the early 70's. All I can say is - given the description of the conditions and the door - this is one I'd be happy to build for a client. However... I'd only build it for them after fully appraising them of the likely outcome of trying to finish such a construction with a clear finish... or even a dark opaque finish (likely, but not certain, failure in a few short years). If they persisted, I probably would have suggested some modifications, but still wouldn't have warrantied it.

I find it hard to say more without knowing a bit more about the situation. Is this a new door? Who built it? What's their contractual relationship with the client? With the door builder? What have you promised the client so far? What are their expectations? What are their hopes? How flexible/reasonable are they? You definitely don't want to get yourself on the hook for future failures in this situation. If you're already on the hook... it's time to back (as gracefully as possible) out of jeopardy. And finally... after the immediate situation is dealt with... maybe it's worth some thought as to how you got yourself into a situation where it sounds like you're a bit over your head? If, of course, that's the case.

MiddleAgesMan
11-23-2009, 03:22 AM
I learned about Nelsonite Wood Stabilizer from some old hippy craftsmen here in Savannah. They have used it for decades and what it does is truly magic IMO. It locks in the dimension of wood at whatever it was when coated. Any change in size due to changes in moisture content cannot be measured with anything other than a micrometer. It is the consistency of water and must be the first thing applied to a fabricated piece. You can't pre-coat parts because it prevents glue bonding. An added benefit is that it calms down wild grain woods such as soft maple, evening out (but not changing) the stain color-variation.

David G--I don't know what is in it but it's widely used in the manufacture of pool cues, not so much in the cabinet industry.

Jim Ledger
11-23-2009, 05:33 AM
Do you really need this job? I realize that work is scarce these days but some jobs are better left alone. The situation you describe, and the advice you've gotten from folks who ought to know, should give you reason to reassess the wisdom of taking the job on. You'll be on the hook if anything happens. The doormaker will probably blame any failure on the quality of your finish.

Only you have the full picture, but from an outsiders viewpoint, I'd walk away from this one.

jgmarine
11-23-2009, 07:19 AM
Hi,
You might cut the ctr of the pannel as best you can (1/8" or so) vertically, and install a center piece to cover expansion etc.

Jack

kc8pql
11-23-2009, 07:44 AM
Do you really need this job? I realize that work is scarce these days but some jobs are better left alone. The situation you describe, and the advice you've gotten from folks who ought to know, should give you reason to reassess the wisdom of taking the job on. You'll be on the hook if anything happens. The doormaker will probably blame any failure on the quality of your finish.

Only you have the full picture, but from an outsiders viewpoint, I'd walk away from this one.
What Jim says.

Bob Smalser
11-23-2009, 07:49 AM
I agree with Jim and David.

http://pic20.picturetrail.com/VOL12/1104763/3075040/364231033.jpg

The problem with a 30"-wide, single-board panel is that it probably came from a 35" diameter log, which means it's the first flatsawn board taken above the pith as shown above. (Ignore the rest of that graphic as the labels for rift and qsawn are reversed.) While once possible, the 6'-diameter mahogany logs necessary to mill boards this wide that don't contain short-grain pith wood are so rare today that your chances of being lucky are almost zero.

So not only will it cup seasonally like the top flatsawn board in the graphic below, the wood's natural fracture lines along the rays (which run radially from the pith) create such a weak center that eventual cracking there is almost a certainty.

http://pic20.picturetrail.com/VOL12/1104763/3075040/189555324.jpg

Mrleft8
11-23-2009, 09:41 AM
If it's not veneer over plywood, it's going to shrink and at best leave a shadow line, at worst it'll leave a gap that cold air can frolic right through. If it is a solid piece of lumber, then you should try to center it in the rabbet, and then put 1 pin through the whole schmear top and bottom to keep it centered so that any shrinkage occurs on both sides equally.

gofish
11-23-2009, 09:45 AM
Thanks all for your sincere help.
I've promised the homeowner nothing more than a beautiful finish (well within my scope) that should remain maintenance free for the first few years.
I can easily back away from the project and will explain to them the challenge involved. I certainly don't want to be involved in what looks to be a big and costly dissapointment for the owner.

The door was manufactured up near the NY / Canadian border. It was designed and built to meet certain architectural styling. Don't know the manufacturer.

It's a shame because it's a magnificent piece of work. I was looking forward to bringing it to life.

Thanks again - Ed

Jay Greer
11-23-2009, 10:25 AM
http://im1.shutterfly.com/media/47b9cf02b3127ccef8fbafa04ba800000040O00QYsmrNy5bsQ e3nwg/cC/f%3D0/ps%3D50/r%3D0/rx%3D550/ry%3D400/
It is possible to get wide mahogony here is some of the planking stock that is being used for vapor. It is African mahogony 2"x4'x35'
Jay

Bruce Hooke
11-23-2009, 11:51 AM
Thanks all for your sincere help.
I've promised the homeowner nothing more than a beautiful finish (well within my scope) that should remain maintenance free for the first few years.

Based on my experience with boats, varnish alone will not meet this standard. Varnish outdoors seems to need maintenance every year and often more frequently than that. Sure you can wait a couple of years before doing any maintenance, but at which point the varnish will be flaking off and the wood turning gray underneath. At that point refinishing is a major chore. On the other and, if done regularly then "refinishing" should be a matter of a light sanding and laying on another coat of varnish. However, the chances of convincing most homeowners to take such an approach is small!

I am wondering if there are any of the catylized (two part) finishes that would do the job without locking the panel in place?

SMARTINSEN
11-23-2009, 07:26 PM
Gofish, can you post a photo?