Posted by Finnegan on 02/23/15 - 4:45 PM
#3
As you can see from the Personal Website link, all of my Whalers have varnished teak and mahogany, and for years I have been using the "washer" solution. I have a lot (too much!) experience in Whaler varnished wood work, and have learned all of the pitfalls also.
There are two types of screw fastener conditions used on all of the classic Whalers that require a washer.
The classic trim ring detail requires a FENDER washer of the same size, and in most cases these were #10 screws. The only good source I have found for these smaller diameter fender washers is West Marine, who has them in both 5/8" and 3/4" outside diameter fitting a #10 screw. 1" diameter fender washers found in the hardware stores are too large. Buy/order a package of 100 when you determine the size that works. Doing this keeps the washer from "walking" when it is tightened down, which is why conventional sized 1/4" washers don't work well. For the #14 screws Whaler used for major connections, the 1/4" washer does have to be used.
The other screw condition you will often encounter is the countersunk oval head screw, #6 and up. These will also cut into and tear up a varnished surface upon tightening. What I do here is drill out the countersink 3/8" dia drill about half the depth of the wood (thereby preserving the exact hole location on the back side), insert a matching wood peg, sanded flush, then re-drill a clean hole through the peg from the back side. This eliminates the countersink and leaves a flush top surface. Then, not re-using the oval head fastener, I replace it with a pan or truss head screw/bolt, and use a conventionally sized washer unter it. Truss head screws look the beat, but are hard to find except in bult bags from West Marine. But I think they are worth the effort. Also, often after varnishing, the holes have to be re-drilled so that the fastener passes through easily, without thread grip.
You can see examples of both conditions in this photo:
http://smg.photobucket.com/user/lgolt...2528992786
Here is an example of the #14 screws:
http://smg.photobucket.com/user/lgolt...1215495435
WORD OF CAUTION: I have learned the hard way that the varnish has to CURE FOR ABOUT A MONTH before using these washers and re-installing the wood. If not, the WASHER itself will BOND to the varnish, and when the washer is removed (pryed off!) it will really do some damage to your finish, taking the varnish right off. When connecting two varnished pieces together, the curing time is also needed to prevent bonding.
So plan ahead with your timing and let the finsihed varnish work cure in a heated environment.
If you do have fasteners with varnish bonded to them after removal, you can soak them overnight in a cup of one-step teak cleaner to remove it. You can also clean up teak oil stained fasteners this way. ALL teak oils have varnish in them, to varying degrees, so ALL teak cleaners have the ablility to cut and dissolve varnish.
Once agin, using this washer detail, the operative word is cure, cure and cure before re-installing. The longer, the better.
Just for reference, I stain all my wood, teak or mahogany, with ZAR brand #120 oil based teak color stain. It gives extra UV protection, and almost completely eliminates later years yellowing. I use Z-Spar #2015 Flagship varnish, which also has high UV proection, 10 to 12 coats. The stain looks deceptively dark going on, but after all the coats of varnish, barely looks any darker than un-stained wood. I know this is a contrarian opinion and practice, but after years of exposure, none of my varnish wok shows any indication of yellowing.
Edited by Finnegan on 02/23/15 - 4:55 PM