Applying Veneer Over Interior Wood ?

[SvenG]

The great porthole replacement project has begun

As I mentioned in another thread, old porthole leaks have stained some of the surrounding interior teak. There is only one place where a ~1" square lost a top laminate layer, otherwise the wood is level and sound and the damage is only cosmetic.

I now have two gorgeous 4' by 8' sheets of wafer thin book-fold teak to layer on top of the discolored areas. Since I have never done such a lamination job I thought I'd see if there are any do's and don'ts that I should avoid learning first hand ?

The teak laminate is wood backed and perfect, no discoloration, flaws or cracks.

I really don't feel comfortable using contact cement since the underlying surfaces are curved and I'd have to be very lucky to get it aligned perfectly right off the bat. Could I use a 5-minute epoxy instead of a contact cement ? 5 minutes would give me enough time to re-align the pieces.

If I don't use a contact cement would it be reasonable to use pins (the kind used in sewing) to hold the laminate in place on the near-vertical surfaces ? I think the laminate is thin enough to easily push a fine pin through into the underlying plywood and the small holes should be invisible with the first coat of varnish.

Is there any need to first coat the back side of the laminate with a penetrating epoxy before gluing it in place ?

What else should I have asked ?

Thanks,




-Sven

[Boomp]

I would like to see some photos of what you are doing. Where do you get teak veneer? I have a couple of places on my old boat where that would be a big help. I imagine you could just use carpenters glue, elmers? but I know there are many on this site who can offer expert advice, so I wait with baited breath

[Tia Bu]

I've tried both contact cement and epoxy and have not been happy with either result. Contact cement worked much better than the epoxy. Suggest you get some old pieces of similar wood and make a few practice runs before you apply it on the boat. It's tricky.

[PAR]

The wise thing to do is make an accurate template of the veneered area. Stiff cardboard (not corrugated) will make a fine template material.

Veneers take some experience to work with, some level of expertise. Contact cement is typical, so is epoxy. Epoxy requires you vacuum bag or other wise insure full surface contact. Contact cement requires you jig and position accurately before surfaces touch.

Don't waste you time with penetrating epoxy. This stuff has very limited uses and frankly isn't worth the money you spend on it.

Pin holes will be visible through the varnish, quite visible in fact. Tacks and staples are one way of positioning and locking it down, but you will have these scars afterward and it's an amateurish way of doing things.

Make your template, you'll see the shape is really odd if there's any real curve to deal with. It would be helpful to see photos of the areas, but I suspect you'll have to disassemble a fair bit of interior to have a flat landing area for your veneers.

If you only have a 1" square area of damage and the rest is sound, why aren't you refinishing the veneer and making a clean repair on the damage?

[SvenG]

Originally Posted by Boomp

I would like to see some photos of what you are doing.

I'll post some when I get some worth posting. For now just the two sheets of veneer will have to do

Where do you get teak veneer?

I asked a carpenter who was working on his own boat where he would get marine plywood and veneers. He suggested Weber Plywood and I ended up dealing with Brad Moroe:

WEBER PLYWOOD & LUMBER
155501 MOSHER AVE
TUSTIN CA 92780

714 259-1100 EXT 114

Of course, unless you are in S. California that address probably won't help you but asking a local shipwright or carpenter is probably the best way. Before my purchase last week I'd never dealt with them and have no relationship with them other than being a happy customer.



-Sven

[SvenG]

Originally Posted by Tia Bu

I've tried both contact cement and epoxy and have not been happy with either result.

What was the problem you ran into with the epoxy ? I assume the contact cement problem was alignment ?

Originally Posted by PAR

Veneers take some experience to work with, some level of expertise. Contact cement is typical, so is epoxy. Epoxy requires you vacuum bag or other wise insure full surface contact. Contact cement requires you jig and position accurately before surfaces touch.

When you say "jig" you mean setting up some alignment guides ?

If you only have a 1" square area of damage and the rest is sound, why aren't you refinishing the veneer and making a clean repair on the damage?

I don't think I can get rid of the discoloration of the current surface. Are you suggesting sanding and bleaching or something like that ?

Thanks,



-Sven

[PAR]

Naturally, veneers will need to be precisely positioned over contact cement, unless you can install over size and trim to fit. Trimming to fit generally requires you disassemble everything and have clean edges to work a laminate trimmer against, though you could do it by hand if you must.

Why can't you cut out the 1" square area and piece in a repair? This is the usual method. If done with precision (like all veneer work) then the seams will be barely noticeable. Grain matching will hide at least two of them.

Bend a piece of cardboard around the veneer area and see what you have to work with. This will usually reveal the best method to approach the repair. Veneering in place, on the boat is going to be problematic at best, but maybe you'll get lucky and the veneer can conform to the shape without resorting to vacuum bagging or other gymnastics.

[Tia Bu]

Par sounds more experienced and knowledgeable. The contact cement was not so hard to line up. If you get the positioning a little bit off, you can correct with some gentle sanding at the overlap. But it's hard to get a good, tight bond veneering in place on the boat. I squeegeed a lot, and there are still a few small voids.

With epoxy, it was even harder, and I had to resort to tacks, etc, to hold the veneer in place as the epoxy set. Even then, the result was a wavy, epoxy-hard finished product that I'm either going to have to sand down and redo or just replace altogether.

That's why some practice boards may be a good approach.

[SabreKai]

I did a repair of a fire damaged boat at PCYC about 20 years ago using veneer over the damaged bulkheads. After removing the scorched layers with a disk sander, I made up patterns using thin cardboard, transferred that to the teak and then applied it with contact cement. Since most of the pieces bordered on a straight edge, getting the alignment wasn't too difficult, just butt it against the trim at the right height and apply pressure. It worked out pretty well, the only difficulty was getting some of the smaller bits to fit under the side racks in the vee berth. Also to remember to make sure the grain was parallel on all the pieces so they would appear as one large sheet as the original material did. As for applying the teak over a curved surface, it might be a good idea to apply the teak wet and let it dry in position so it will curve better. I've used that process while sheeting models with 1/32 plywood. Let the veneer soak in warm water for a hour, then pat it dry, form it over your curve and hold in place with tee pins. Once dry, remove, apply the glue and replace, again holding it with tee pins.




Sabre

[Stillraining]

Do not epoxy the the back of the veneer...it will make it less bendable and brittel.

IMHO..If its a difficult contour or access...I would not use epoxy or contact cement but a structural drywall adhesive...It will give you plenty of time to adjust your veneer for proper alignment, ability to remove it if absolutely necessary before it sets (still messy) is water proof and it will remain flexible yet hold like nails.

Spend more time preparing contoured pieces of wood and a means to wedge and hold them and the veneer snugly to the shape of the hull then anything else, and you will get a very nice result.

[PAR]

A coating of epoxy on the back of a 1/16" or even an 1/8" teak veneer will not affect the stiffness of the veneer what so ever, particularly if tack free but still "green". Fully cured epoxy will have modulus elongation properties better then the teak itself. If you do elect to use epoxy (which is what I would do) treat the veneer before coating, by scrubbing with a 50% acetone, 50% rubbing alcohol mix first (let it flash off of course) just prior to apply the goo. This will remove the oils and tannins in the wood and a much better bond will result.

Liquid Nails and other such products have no business on a boat. They're fine on static loads that will not see the environmental and physical changes, that marine applications must tolerate. They literally don't stand a chance in the marine environment, usually because they lack the necessary flexibility and moisture resistance. It's been tried, tested and debunked repeatedly in the last decade.

There will be no issue with adjustment time if using epoxy (naturally select the proper hardener speed).

If using contact cement, which is what the manufactures do, a "J" roller will be of great service once you've got it in position. Use dowels or thin strips of scrap veneer to space the veneer off the surface as you position it, then pull the spacers as you get things lined up.

Admittedly, working "in the field" is more difficult. Prep, as in all finish work, is the key to success. Perform "dry runs" so you can arrange clamps, tools, supplies, etc. This is especially important if using epoxy, but just as much with contact cement. If you plan it out right, then the actual "event" of sticking your well sized and prepared veneer will be anticlimactic. The last thing you want is the Chinese fire drill sort of thing, looking for a clamp or other tool, paper towel, etc. as the goo is kicking. Once you get the template made, you'll see if it's possible or not.

[svHyLyte]

As for the use of contact cement, I found that one could cover the cement on the back of the veneer with wax paper once it had "dried", holding the wax paper in place with slips of tape adheared to the face or front of the veneeer. With this one can position the veneer and then slip the wax paper backing off, slowly, starting at a convenient edge of the piece. After the first few inches, the contact cement holds the piece in place after which one can easily remove the wax paper--from top to bottom or side-to-side--while rolling the surface of the veneer with a hard roller as described above. I found that "illustration board" for modestly curved surfaces was useful for making patterns, using double stick tape to hold it in place. For tighly curved surfaces, brown "butcher" paper made fairly good patterning material again with double stick tape at strategic courners. I have also used clear plastic drop-cloth material to make patterns but one must be careful not to stretch the plastic. Frankly, I see no need nor benefit to using epoxy adheasive but it can be used if that is your choice. In that case, you can dab spots of adheasive from a hot glue-gun to hold the veneer in place until the epoxy "goes off" although it's not too effective on tight outside curves.

FWIW...

[sarafina]

Originally Posted by svHyLyte

As for the use of contact cement, I found that one could cover the cement on the back of the veneer with wax paper once it had "dried", holding the wax paper in place with slips of tape adheared to the face or front of the veneeer. With this one can position the veneer and then slip the wax paper backing off, slowly, starting at a convenient edge of the piece. After the first few inches, the contact cement holds the piece in place after which one can easily remove the wax paper--from top to bottom or side-to-side--while rolling the surface of the veneer with a hard roller as described above.

now THAT is valuable info. I have done my research and per all the veneer specialists; in the case of applying it to fiberglass or existing wood the rubber cement is recommended.

But the waxed paper makes it sound MUCH easier to finagle into place!

[PAR]

I've applied a fair amount of veneers and other materials. I'd be afraid the wax would contaminate the bond. Now I would vacuum bag the veneer and not worry about contact issues. Previously, I would have used contact cement. The time tested method is to use sticks or other spacers between the two pieces, until they are positioned where you want them, then you pull a spacer, dowel, stick or what ever and press it down. If you can remove the wax paper without getting wax into the cement, this might be a handy thing, but I've never seen this done, nor used it myself.

[svHyLyte]

The "wax-paper" methodology outlined above was described to me by a fellow who's business involved making furniture covered with laminate. I used the method to replace a number of coverings in our forward and aft lavatories. It is somewhat of a pain in the neck (literally--depending upon location) and sometimes seems to require 3 hands but it did work for us and the surfaces remain sturdy now after 4 years in the southwest Florida heat. Never-the-less, it would be wise to experiment with test pieces in one's garage or workshop before going for the whole hog to develop one's skill, eh?

FWIW...