Why varnish when you can oil?

Some wood surfaces on canoes are oiled and others are varnished. For example, most seats are varnished, most gunwales are oiled.

Oiled surfaces are much easier to renew than varnish. Why do we use varnish? Why do we use both on the same boat, so that you need two materials and processes if you are doing maintenance?

~~Chip Walsh, Gambrills, MD

A good varnish job can more completely
exclude moisture from the wood. But when I finish furniture, I use many coats of Minwax 209 clear penetrating oil. Works well on paddle handles also, although after a renewed application, there may be a tiny bit of sticky feeling at first.

When I made a batch of superlight spruce thwarts for my WW canoe, I knew that oiling, while fine for ash, is not sufficient to protect spruce. So, I first sealed all surfaces with West epoxy, and then I applied a UV resistant spar varnish to protect the epoxy from sun.

Varnish can be over-valued. I assume people expect the same appearance on boat wood that they expect on their fine furniture. Not that it makes sense…

My take…
Varnish seals well, but doesn’t stand up all that well against scratching and chipping compared to oil. Seats and thwarts don’t generally get the abuse that gunwales do. So gunwales are oiled, seats and thwartes varnished. It’s easier to touch up an oiled piece.

I think the oil is just so much easier to touch up that it appeals to me for everything. Over the last year I did rehab on the wood work of four canoes. My swift had varnished gunwales and oiled everything else. I stripped the gunwales and oiled everything. Me like. Thwarts and seats on my vinyl gunwaled Bell all got stripped sanded, bleached to get rid of the mildew stains from the open vessel cells of the spring wood where the varnish was chipped scratched etc, and then restained and oiled everything. On the two canoes I redid for my father-in-law, a Mad River and an Old Town I cleaned sanded and revarnished all the wood, knowing that my father-in-law would never get around to re-oiling anything. I wanted maximum protection under extreme neglect. One of the boats is technically mine. “Take your pick,” says I; “Both” says he. Like a little lad at Christmas he was.

Point being: I’d like everything oiled, but I can see where varnish is better for some.

Good points. Back in ‘73 I ordered a
Mad River Compatriot (a little 13’ V-bottomed solo boat), and Jim Henry said if I wanted spruce rather than ash gunwales, they would be stiffer and lighter, though more easily broken. When the boat arrived, the spruce gunwales were carefully varnished, but of course that varnish took a lot of wear. I oiled it sometimes, but spruce really does not stand up to water exposure like ash, even if the spruce is oiled. So for low maintenance with oil, ash gunwales and ash thwarts are the best. Some other woods like mahogany and cherry also respond well to oil.

Varnish and oil
Let’s cut to the chase!

Oil is fine if renewed several times a year. Most paddlers don’t do that.

The existing situation: varnished seats and thwarts verse oiled rails is a function of conditions.

Every manufacturer buys seats and thwarts and drops from Eds or Essex. They have a dust free finish room and varnish the parts; they arrive sealed.

Rails usually come from Essex and Eds too, but they need to be drilled, sanded, installed, resanded, then finished. Most boat builders do not have a dust free environment, so oil is much easier.

Poly lasts longer than oil, oil is easier to keep up. Armada and Cepetol seem better yet. We’ve several sections of cherry rail stock with various treatment screwed to an outdoor boat rack since last fall. Maybe we’ll have data to share by this fall.


– Last Updated: Jul-04-07 7:02 AM EST –

There are lots of myths around real spar varnish. Fact is it has been used on sailing vessels for centuries for good reason. Water,UV protection, and the finish is somewhat flexible expanding and contracting with the wood.

Maintenance for me involves scuffing with sandpaper every - say 5 to 10 YEARS and going over it with a brush. How hard is that? I don't have to go find that Watco can every six months either!!

Another benefit is you can strip it and it doesn't darken the wood. I've stripped canoes that are 50 to 100 years old, and the wood underneath looks like new. Give it new good quality marine spar varnish and it's good for another 50 years.

Spruce was a wood of choice for rails for wood canoes from Old Town and many other canoe companies. Strong, lightweight, flexible, and more rot resitant than ash. I bet nearly a quarter of a million wood and canvas canoes had spruce gunwales.

Okay - you can flame me now. I have to go varnish my 1920 Bobs.

this debate has and will go on…
…for many moons because there is plenty of room for opinion & preference.

I agree with others that it depends on the species of wood & it’s use, exposure, conditions, etc.

I think teak generally responds better to oil finishes, but have known sailboat (and powerboat) owners who argued about the best substance endlessly. Sikkens cetol was the one my OCD sailing friend had settled on the last I heard.

Yesterday I stopped to yap with a craftsman who was replacing a fir tongue-in-groove porch floor with Phillipine Mahogony and he was applying Phenetol (? sp?) penetrating oil, which was what the specialty hardwood supplier had suggested…it had a very strong aroma that could be detected blocks away. Not sure I could handle working with that stuff…

Aesthetics plays a part
I am a fan of oiling, but have to say that a nice varnish job really brings out the beauty of the wood. If you prefer time on the water to time with sandpaper and a brush though…

Not flaming you, but spruce has NOT
been as rot-resistant as ash in my boats when the finish breaks down in midseason. In fact, I have never seen white ash thwarts or other ash parts even start to rot on the surface the way sitka spruce does. Based on this personal observation, for me it is epoxy and spar varnish on spruce, and oil for ash.

Are we talking about different kinds of spruce? I inherited a big pile of sitka spruce from a guy making his own biplane, and I have never bothered checking any other spruce variety.

oil vs. varnish
The oil-gunnels-varnish-everything-else doctrine has at its root the advice that accompanies every Mad River canoe, and when this subject came up here a few years ago, I wrote to Epiphanes for their opinion. Their opinion (in my brief paraphrase) was “Bullshit!” Modern spar varnishes, they say, are plenty flexible and are formulated with oils that protect as well once scratched or scuffed. True, they have an interest in the question, but they know a thing or two about wood and water too.

So the last boat I did, I sanded, bleached, and dug out the rot on the inside of the outers (this is, IME, the most vulnerable part of the wood-outfitted boat, and the easiest to access - leave everything inboard intact [clamp some long thwarts across the whole thing to keep it in position] and just unscrew the outers - they come off and go back on with ease) filled the gouges with epoxy + filler, and finished with four or six coats of Epiphanes. It was beautiful.

I apologize for the anticlimax, because I was preparing the boat for sale, and the buyer never sent me promised in-service reports.

I liked the results so much better than years of oiling that I’m going to do the same for my like-new Kevlar/wood Vermont Malecite.

About the epoxy coat: Some recommend using a so-called penetrating epoxy. West Systems will indeed sell you such a thing but the Gougeon brothers recommend against using it. They say that the thinners they have to add can do nothing but hurt the mix and the result. Instead, they recommend pre-heating the wood, maybe with a shop heat gun, hair dryer or sunshine, and the heated, thinned epoxy will paint on and penetrate like water.

This worked slicker than (insert vulgarity of your choice here.) I kept my mix pot in a bigger pot filled with ice and water to extend the pot life, then worked the brush along with the heat gun.

It worked so slick that I used the finish on my African mahogany pole. When I finished, it looked like part of a Steinway. Now, after more than a year, under a hammering far worse than most gunnels ever get, it’s not as pretty but still pretty well protected.

It’s a lot of hard work, but the result, I think, is worth it.


Oh, and I would not describe Sitka as
"flexible." Comparing Sitka to ash is kind of like comparing carbon fiber to Kevlar. Ash is tough and flexible. Sitka is VERY stiff and strong for weight. The sitka thwarts I have made are much less flexible than the ash thwarts they replaced, but I don’t stand on thwarts. I expect them to be strong mainly in one dimension, but if they have to also withstand the upward force from a minicell pedestal, I simply carve them thicker where they need to be.

On the flexibility issue, I would say that sitka is both stronger and a little more flexible, weight for weight and thickness for thickness, than the high quality redwood I have sitting around, or the deck cedar I’ve worked with.

Mmmmmm…African Mahogany…
I used to dumpster dive for that stuff at the Martin Guitar factory in the late 60’s & still have some left. It is as beautiful as wood can get.

Not sure why one would want to heat
or thin for epoxy penetration unless the wood is bad. West epoxy stands up very well on my wooden paddle shafts.

Taking the case of interior furniture and floors, it isn’t as hard to lay on multiple coats of Minwax 209 Clear as it is to do just a few coats of varnish. The oiled result is hard, resistant to water, and easily repaired if dented or scratched. We oiled a maple floor and it worked much better than the varnishes in our present home.

Varnish has a look that some people prefer, and some people get better at applying it than I am. I shudder to think of what would have been involved to properly varnish the 1700s turnings on the legs of my harpsichord and clavichord. Even some of the professional builders were using oil rather than varnish.

Why is polyurethane never mentioned?
Wouldn’t polyurethane be perfect? It’s tough and water-proof.



– Last Updated: Jul-04-07 8:45 PM EST –

From what I know, poly lacks the flexibility needed on a boat that is expanding and contracting with moisture.

The spruce used on canoes in eastern North America was/is eastern spruce (white/black spruce).

Spruce was/is used in airplanes because it was flexible, lightweight, and strong. Good qualities for a canoe too - no?

Some polyurethanes will work, but
should not be over-valued just because of the word urethane. As for its toughness or hardness, I just used some UV resistant polyurethane varnish to see if it would protect a glass/epoxy wear patch on a Royalex boat. The varnish is not holding up well at all, and it appears it is neither hard enough nor tough enough. Of course this has nothing to do with its use on wood, and the same varnish seems to be protecting the epoxy that is protecting, in turn, my light spruce thwarts.

oiled wood
An oiled wood surface is great assuming you live in a place with no polution, which unfortionately not many of us do. Oiled wood will turn black sucking in every bit of dirt in the air if not constantly maintained. Varnish if done properly will hold up for many years with little maintenance, this though included not leaving it sit out in the sun when it’s not used.

Spar varnish is the way to go
Oils are nice for motorboats and teak trim.But, they tend to darken/blacken.

Canoes require an attractive protective coating. Spar varnish provides this protection. My wooden canoes are all varnished with a good quality spar varnish.

Keep poly off of your canoes! It will blister and peel. Definately do not put poly over varnish.

Some of the rap on blackening of oil finishes comes from boats that have been maintained using linseed/turpentine. The linseed is food for the fungus, but some of the boat oils have additives that kill it off. Too, linseed has no UV countermeasures.

Varnish everything.