Polyurethane or Spar

[Nachako]

I know this subject was discussed to death on the old board . Someone had to bring it up again for us newbies . ( Also I wasn't paying attention then ) Peter Hyde gave me a good breakdown on how to apply 2 part polyurethane and I have used spar varnish on my bamboo rod rebuilds . But I am still undecided . So my question to this board is who is using what ? why ? and how many coats ? So any insight would be appreciated. Thanks Paul

[Juneaudave]

I used 6 coats of Interlux Schooner on my canoe. It was readily available in my area and I thought it gave the yellow cedar on the boat a nice golden hue. My thinking was that spar is tried and true, I knew it would work, and that I could repair the scratches fairly easily. Being my first canoe, I was more confused about application. I ended up using foam brushes except for the first and last coat, and wet sanded with 220 between coats. I also wet down the floor of my garage a bit. On the first coat, I got some dust contamination even though I had the garage pretty clean. I think there might have been some static electricity that the moisture took care of. Having said that, there have been a lot of products discussed on this forum that people swear by ranging from two part polys, auto clear coat, etc....Let us know how it turns out.

[Rick]

I'm going with spar first, for UV protection, since it seems the UV blockers in both polyurethane and varnish will break down eventually in sunlight. Ted Moores in Canoecraft says that several coats of varnish will last at least three years, while Todd Bradshaw has posted here that revarnishing should be done every year to be sure that the UV protection is there.

Spar is also easier to reapply, I've recoated rawhide seats without any sanding prep at all, and the varnish stays on.... I'm not sure how polyurethene would have done. Spar is the more traditional finish and maybe more predictable and reliable.

[Steve Lansdowne]

Seems to me that the frequency with which you need to reapply spar varnish to keep the UV protection good depends on how much your boat has been UV exposed. Thus, saying that reapplying varnish will depend on UV exposure. I also read not long ago that once the varnish stops being shiny, that means the UV protection has gone. Has anyone else heard this?

[Glen Smith]

Yes, I have heard this a lot. I believe it is based on the fact that a shiny surface will better reflect the UV rays and a less shiny one will absorb more. I have two boats that I built three and four years ago and they still have the original varnish. They haven't seen much use but they are exposed to the elements year round. However, I am talking about Quebec sunshine and not the southern States.