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fcooper
12-23-2011, 08:09 AM
I am planning to build "Liz", Ken Bassets Lapstrake pulling boat. I will use the traditional steam bent oak ribs on lapstrake with copper rivets and nails.

Question: What about finishing under the ribs. I plan to have the inboard finished bright with a Maloof mixture I use on fine furniture. My concern is the bare wood where the rib contacts the strakes, and the small triangle space between the ribs and the strakes. Should I put a coat on the inboard strakes before installing the ribs?

Also, I assume steaming oak raises the grain on oak? What to do prior to steaming to have a good surface on the ribs?

Lots to learn and looking forward to making a functional work of art.

f

Peerie Maa
12-23-2011, 12:26 PM
Most builders earning their living building boats don't finish under the ribs. I have read of pouring a pint or so of varnish into the finished boat and rolling the boat around on the floor until the varnish seeps behind all of those hard to reach places. There is nothing to stop you putting a couple of coats of finish in the hull before you timber out, but you will have to wait for it to harden right off before you start timbering.

Dan McCosh
12-23-2011, 12:52 PM
I haven't heard of a furniture finish with UV protection. Would this one have it?

ARW123
12-24-2011, 04:12 AM
My concern is the bare wood where the rib contacts the strakes, and the small triangle space between the ribs and the strakes. Should I put a coat on the inboard strakes before installing the ribs?

Also, I assume steaming oak raises the grain on oak? What to do prior to steaming to have a good surface on the ribs?


I have recently replaced 50+ steamed frames. Each was passed through a thicknesser and chambfered the inboard corners with a plane (to save my knees crawling about inside...) even when as smooth as a baby's bum, as you say once steamed the grain is lifted, nothing I can think of would prevent that.

Ref the bare wood; the strakes under the timbers/frames/ribs were soaked in Cuprinol 5 star (or the Sovereign equivalent at 2/3 the price), followed by thinned red lead paint in the bilge (above the water line no red lead). As for the small trinagular space (or limber holes), my approach was that the underside of the timbers/frames/ribs would have to take their chances - I wasn't going to remove a dry fitted frame to paint it; life is too short and more often than not it was too much like russian roulette bending the damned things into the turn of the bilge in the first place....

You could - if you were really masochistic use one of those cranked radiator brushes, or for the smaller limber holes, perhaps a piece of Terry towlling and rubber gloves, soak a strip in the poison of your choice and pull through the limber holes backwards and forwards....but on balance I would prefer to clean out my sock drawer.....!

Bob Smalser
12-24-2011, 05:00 AM
Use a conventional alkyd spar varnish, apply the first coat generously and thinned severely (ie thinner than 50-50), and it'll wick under the framing members for you.

Avoid interior finishes intended for furniture. They offer little water resistance, poor durability and zero UV protection. Plus those with too much linseed will turn black in the sun. And after they fail a year or so later the residual urethane plastic in them (which is hard to remove) will interfere with getting a uniform color in the spar that should have been used in the first place.



Finish #4: Sam Maloof's Finish



Requires many coats to get reasonable depth and protection
Lengthy application time for large surfaces






The Sam Maloof finish consists of two finishes: A varnish/oil mixure followed by an oil/varnish/beeswax mixture. The first mixture is applied until you are satisfied with the build-up. Then you apply the second finish, which does require some elbow grease! You can purchase the finish pre-mixed from Rockler, or you can mix your own. I provide two Mixture 1 recipes. Mixture 1 Version 1 is the traditional Sam Maloof finish. It takes a while to dry--leave at least 24 hours between coats. Mixture 1 Version 2 is an oft-used finish that provides a little better penetration, is easier to apply, and dries faster.
Mixture 1 Recipe (Version 1) Mix equal parts of the following:

Boiled Linseed Oil
Raw Tung oil (not Waterlox, Dalys, or other tung oils containing resin additives)
Semi-Gloss urethene varnish
Mixture 1 Recipe (Version 2 - Easier to Apply, Better Penetration, Dries Faster) Mix equal parts of the following:

Thinner. Use paint thinner, mineral spirits, or naptha. Feel free to use a bit less thinner and more varnish or oil. The thinner is present to help the finish penetrate the pores of the wood, rather than lay on the surface.
Varnish. Virtually any quality varnish will do. I prefer a standard oil varnish rather than a fast drying varnish.
Oil. Use either boiled linseed oil or raw tung oil. Again, do not use Waterlox, Daly's, or other tung oils that have added resins.
Mixture 2 Recipe Mix 2 handfuls of shredded beeswax to equal parts of boiled linseed oil and raw tung oil. Heat the mixture in a double-boiler on an electric hotplate just until the wax melts. Due to the volatile nature of the ingredients, brew your mixture outdoors. When cooled, the mixture should have the consistency of heavy cream.

General Procedure Apply three to four coats of Mixture 1. Let oil sit on surface for 5-10 minutes. Optionally, sand mixture into wood using 400-600 grit wet and dry sandpaper. Remove excess oil with a clean cloth/paper towel. Allow at least 24 hours drying time between each coat. Apply two to three coats of Mixture 2. Rub Mixture 2 into the surface very vigourously--it is suggested that when your fingers start to get hot from the rubbing, you're applying it correctly.

From what I have read, Sam Maloof's employees sand to 400 grit, then use #0000 steel wool to create a very fine surface. Then they take a very soft rag - a sort of toweling - and run it over fery carefully. Oil finishes require a much smoother surface than thick surface finishes (varnish, lacquer). However, for this finish, I stop sanding at 220 grit, and use the wet sanding technique. It produces an ultra smooth surface by not only "sanding", but sanding wet fibers and filling microscopic pores. Here are Sam Maloof's own words:
"...we use my own finish that Rockler sells - one third glossy varnish, one third boiled linseed oil, one third tung oil. I use that on everything, tabletops and all," he said.


Last, the key to achieving a good finish on steamed parts with raised grain is sanding between coats of finish after the ribs are installed. But to speed up the process you can apply a coat of primer (thinned varnish or red lead for painted parts) to the ribs before steaming them.

Bob Cleek
12-24-2011, 06:32 PM
Amen, Brother Smalser!