Natural finish suggestions?

[Dagon]

Hi,

My current project is a Bolger Cartopper. I intend to paint the exterior and leave the gunwales and interior natural (I'm building with mahogany marine ply). I will bright-finish the gunwales, rudder cheeks, etc. but while I love natural wood, I really don't care for glossy varnish in the interior. What are some other possibilities? I've seen some mention of 'boat soup' and linseed oil. What other penetrating oil-based options are there? And what about products like Thompson's Water Seal (you know, for decks and fences)? Or urethane finishes?

Thanks,
Kellan

[jimstitt]

I did some tests of 2/3 Thompons, 1/6 boiled linseed oil, and 1/6 turp. I looked super for about a week, a very low gloss, and the water beaded up well. I did a piece of WR cedar, white oak, and a little purpleheart. After about 2 weeks strait without sun, and nearly continual rain on the wood the cedar and oak had darkened conciderably, and now, about a month later, the oak and cedar have little black spots on them, mold of some sort -> of course this was all in a temperature range of 40-50 degrees, and continual wetness, my driveway has moss on it...
I am still looking for the same sort of finish you are but havent done any other tests.

[mariner2k]

Try a product called penofin.
www.penofin.com (http://www.penofin.com)
It is fairly inexpensive (30.00/gal), can be bought clear or slightly pigmented, and available at some lumberyards. A friend of mine turned me on to it. I've used it on my rail and bowsprit. 3 coats on the sprit and it still looks good a year later. I've also used it on mahogany decks. Maintanance involves washing and more coats. Well worth a look.
mariner

[Wayne Jeffers]

I have a poor opinion of Thompson's water seal.

I believe it's mainly a wax mixed in mineral spirits. My experience is that it doesn't repel water long enough to be worth the trouble to apply, let alone the money it costs.

Also, it provides wonderful nourishment for algae and other stuff that will grow where it's damp and make things really ugly. (And obviously it contains no herbicide.) :(

I'm at a loss as to how they keep getting anybody to buy it. :confused:

Wayne

[Dave Williams]

Re: Penofin:

The manufacturers of Penofin claim it is formulated from Brazilian Rosewood oil and is from sustainably harvested forests.

There is a thread over in people and place about Rosewood. One of the posts attests that Brazilian Rosewood is an endangered species and can not be legally harvested anywhere in the world!

Any opinions about this?

Dave

[Keith Wilson]

IMHO, a bright finish inside a taped-seam hull will look pretty wierd no matter what you use. Even if you use epoxy with wood flour for for the fillets, they'll look significantly different than the planking (no grain, a different color), and the Cartopper has LOTS of fillets. Fillets with anything else will look much worse (grayish white if you use fumed silica) If it were my boat, I'd paint the inside. If you want some varnished wood, why not put a half-round just above the upper chine, and varnish the "sheerstrake"?

I think the longest-lasting, least hassle bright finish is Cetol over CPES, although some don't like the orangish color of the Cetol. West Marine makes a knockoff ("Wood Pro" or something like that) which seems, in my limited experience, to be as durable, with a nicer color

My favorite recipe for "boat sauce" (there are many others) is:
- 4 parts boiled linseed oil
- 3-4 parts turpentine
- 1+ parts japan driers
- 1 part pine tar (or less) - more makes it darker and slower-drying
- up to 4 parts spar varnish (I throw in whatever leftovers I have around)

It works well on cedar (great for porch furniture), but I don't think I'd use it on plywood/epoxy construction

[Scott Rosen]

For the most part, I don't like the look of plywood brightwork. The radial cut of the plies just looks unnatural to me on a hull, when compared to, say, quarter-sawn lumber. Varnished plywood, or worse, oiled plywood, still looks like plywood. Plywood has a lot of advantages over lumber in some uses, but beauty of appearance is not one of them.

Plywood calls out for a high-tech finish like epoxy sealer and paint. If you use a two-part linear polyurethane paint over epoxy, you will have the most durable finish imaginable. The plywood is stable enough to support a finish like that for years without any maintenance other than washing.

If you like putting a fine finish on thin veneers of exotic woods, then stick with interior furniture.

[Dagon]

Thanks for the replies. In general, I agree with Scott about bright-finished plywood. On my previous project however, I found that mahogany marine ply can yield a very nice finish. Check out the CLC kayaks. Taped seams can be made to blend reasonably well with the proper amount of wood flour in the mix. The thing that has inspired me to go more natural with this boat is the appearance of Iain Oughtred's boats, which are also made of ply. In fact, I'm using this boat as a learning project before I attempt an Oughtred design.

[Jeff Evans]

[QUOTE]Originally posted by Dave Williams:
[QB]Re: Penofin:

The manufacturers of Penofin claim it is formulated from Brazilian Rosewood oil and is from sustainably harvested forests.

There is a thread over in people and place about Rosewood. One of the posts attests that Brazilian Rosewood is an endangered species and can not be legally harvested anywhere in the world!

Brazilian Rosewood "Dabergia nigra," is not just endagered, it is listed on Appendix 1 on the Convention on the Internationl Trade of Endangered Species. This distinguished list includes such species as Pandas, all the big cats (lions, tigers, leopards etc.). D. nigra cannot be cut except for scientific research.

However, the Penofin web page states that their product is made from Brazillian Rosewood seed oil that is sustainably harvested. If this is true, then it seems that it would be a good product to support, as it would create sustainable jobs in an unstable economy while encouraging the conservation of a critically endangered species. Check out this link if interested. I have no idea who this group is, but they seemed to like the product :http://www.greenculture.com/ps/pp_rf.html

[Venchka]

Dagon,
You stated: "The thing that has inspired me to go more natural with this boat is the appearance of Iain Oughtred's boats, which are also made of ply. In fact, I'm using this boat as a learning project before I attempt an Oughtred design."

Iain Oughtred uses VARNOL ( a varnishing oil) made in Norway for his bright finish. Alas, the manufacturer of VARNOL in Norway chooses to ignore the North American market. The product is unavailable here at the present. Pity.

Wayne

[Dave Williams]

Jeff,

Thanks for your responce. That was helpful! Sounds like an interesting finish for britework. Might give a try.

Dave