Spar urethane vs Spar Varnish vs Polyurethane

[Gunguy05]

If we are talking interior, which of these is the best / and or most economical?

On my last build I used Cabot spar varnish on everything. Now I'm looking and it looks like I see the other 2 carried in the box stores. Both are minwax or Helmsman minwax. The varnish is by special order only.

Just wondering what the experience of others is here for protection of interior surfaces. What have you used?

[jonw]

Since UV protection is not an issue for interior surfaces Helmsman is overkill.

I used water-based Minwax Polyacrylic polyurethane. Goes on well, easy to clean up with soap and water, and easy to reapply on any wear areas that need some touchup later.

[tony.latham]

I've been using the Minwax poly for years and really like it for interior and working surfaces such as the counter top. I plan on three coats with a light sanding from an orbital sander in between coats. If it's a sunny day, I can get two coats done by applying in the shade and moving the part to the sun.

It hardens up the surface but will not chip like some varnishes do.

I need to try a can of the water based stuff sometime.

Tony

[noseoil]

I use the cheap Home Delay floor finish (satin urethane). Works fine inside & pretty cheap compared to the good stuff or varnish. No sun or UV protection needed. 10% reduced first coat. Second coat full strength & done, for walls, cabinets etc.

[dales133]

I used waterbased cabbots on my interior walls and i used cabbots oil based floor finish on my hatch ribs abd detail work.
Its great stuff,when you think of the punishment a timber floor gets this stuff should last fine

[Gunguy05]

Since UV protection is not an issue for interior surfaces Helmsman is overkill.

I used water-based Minwax Polyacrylic polyurethane. Goes on well, easy to clean up with soap and water, and easy to reapply on any wear areas that need some touchup later.

I've been using the Minwax poly for years and really like it for interior and working surfaces such as the counter top. I plan on three coats with a light sanding from an orbital sander in between coats. If it's a sunny day, I can get two coats done by applying in the shade and moving the part to the sun.

It hardens up the surface but will not chip like some varnishes do.

I need to try a can of the water based stuff sometime.

Tony

I used waterbased cabbots on my interior walls and i used cabbots oil based floor finish on my hatch ribs abd detail work.
Its great stuff,when you think of the punishment a timber floor gets this stuff should last fine

I think I will try out the water based stuff... maybe this time. I am going to be spraying it (new to me), so I think the water based might be handy for cleanup with the sprayer. If I do go with the oil based I will dilute the first coat. We going using t/g pine on the interior walls that will need to be coated. It is very soft so I want to get a good 3-4 coats on it. I am thinking the dilution might be good since I want it to soak in well (if I go oil based)...but then again, I would suspect the pine would soak it up pretty well anyway.

Thanks for all the input! Not sure how I would have gottne #1 complete or #2 started without all the folks on here!

[dales133]

For big areas definatly try waterbased.
If you change your mind you can always top coat with oil

[anon1]

One thing that I didn't see mentioned is that the "spar" type is a less durable and hard finish.

It is made with more elasticity in it to allow the piece to flex without cracking the finish open. Used on sailing ship spars that hold the sails and flex with the wind gusts.

[drhill]

I have used allot of water based Varathane Diamond Floor finish (on hardwood floors) and have used Deft Water Based Polyurethane and Varathane Diamond Outdoor on my teardrop exterior. The teardrop was finished mid 2014 so too early to judge the longevity of the finish. It is garage stored and it will get a few fresh coats every year, easpeciallt the tongue box and front wall that suffer from road rash.

I did a hardwood floor in a rental house 18 years ago. A few times I have had to do touch up repairs and that is where the water based finish really has the advantage. It goes on clear and stays that way with no yellowing over time. So for repairs, a few minutes sanding and a few refresher coats just in the damaged area and you can't tell where it was fixed. This might also be an advantage if you wanted to change or add to interior cabinets in the future and match your finish.

I think the low odor, quick dry time and easy water cleanup have already been mentioned.