Exterior Door Finish

[Jerry Solomon]

I have a solid mahogany leaded glass (half-glass) front door. It is relatively protected from the direct sun by a 6' wide front porch. However, it still suffers from the exposure. It was stained and then coated with a polyurethane varnish finish. After a couple of years the varnish starts to dull and look bad (mostly near the bottom). I took it down and have it in the garage on sawhorses with the exterior side up. I am not planning to re-do the inside as it still looks great. I am going to strip the varnish, re-stain, and re-varnish. In the past we have had problems trying to apply poly out of a can as it always tacks-up before I can finish the job resulting in a mess of brush marks. Therefore, I have resorted to Minwax Wipe-On poly in multiple coats. My question is: Is the short life due to the Wipe-On poly? Should I be using spar varnish (or something else)? If so, what's the secret to brush-applying this stuff without the too-rapid drying?

[Steve Schoene]

Single part polyurethane varnish is quite susceptible to UV light. If the door were in full sun, the varnish wouldn't have lasted all summer. Using a quality marine spar varnish will add considerably to the life. Marine spar varnish can't be found at any of the big box stores or normal paint stores. Acceptable brands are Epifanes Clear Gloss, Interlux Schooner, or Pettit Captain's. You will need to find these are marine supply stores such as West Marine. West Marine isn't the cheapest source, but I think you have one in your area.

I can't imagine any of these will gel in the can before you finish the project, nor will they get tacky before the job is over unless you wait for really warm weather. Ideal temperature would be about 70°. Do remember to pore out what you will use for a single coat into a separate container, thin it as necessary, and then do not pore it back into the can if you have any left over. Don't thin it in the can. (You will need to thin these varnishes around 10%, maybe a touch more for Epifanes.) For optimum life use about 6 coats, sanded lightly with 320 grit, and applied about 24 hours apart.

The Epifanes is relatively dark in color, so take that into account if you stain.

[Casey Gooding]

I agree to go with a marine varnish like Epiphanes. I use it like a wiping varnish by thinning it considerably with mineral spirits. It takes more coats to get a good build this way, but you can get a great finish without brush marks.

[Larry Edgerton]

It may not be what you want to get into, but I use automotive clearcoats on doors I build for commercial applications. I get the door flat with just plain waterbased clear, when it is perfect I spray it with automotive clear adhesion promoter, the kind used on urethane bumper covers, and then top with automotive clearcoat. The best I have used was Sherwin Williams 7000. Wierd stuff, you buff it when the surface is dry but you can still move it around with your fingers.

I have one bar door that has been abused for 15 years, and opened millions of times, and the finish is still good.

[Steve Schoene]

Goodness, that's about 18 coats to get the recommended dry film thickness. I don't really understand brush marks with Epifanes, thinning just a little--say 15%, gives a varnish that levels very well. You'd have to working at something like 90° to get it to start to get tacky before the brush marks leveled.

[Kent A Bathurst]

I just finished [sorry 'bout that one] a project. WRC arbor and gates for an entrance. The arbor timbers are rough, but the gates were machined to get the dimensions I wanted.

Since I had a nice, smooth surface, and since the project client is next-door neighbor, I decided to use the Epifanes on the gates [note to self: when you tell the client "you pay for the material, and I'll give you the labor", you just chose the wrong end of that log to carry]

I followed the recommended thinning schedule on teh can - IIRC, first coat 50/50, next coat 75 varnish/25 thinner, then coats at 85/15 as Steve mentioned. Rather that the "official thinner" from Epifanes, I also used mineral spirits.

6 coats gloss, followed by 1 coat satin [again, as recommended by Epifanes]. The client wanted the satin finish.

Brushed on, no issues/problems with brush strokes, etc.

You have to realize that the marine version requires scuff-sanding between coats [see note above re: wrong end of the log], which may have contributed some to the look, but I never saw any brush strokes to speak of .

They also have a woodfinish product [I think that's what they call it] that says no sanding required. I didn't look into that, to see if it has the same performance level as the std marine product. If I was gonna do this again, I'd sure as heck check it out, though. I did have a couple questions along the way, and the support guys at Jamestown Distributors were very knowledgeable and helpful on the product.

BOTTOM LINE: If it was my mahogany front door, I wouldn't think twice about using the Epifanes.

[Jerry Solomon]

Thanks for the feedback. We live in the New Orleans area so I'd better get moving as it is already getting above 70F many days. Some of my past problems have been made worse by trying to finish something at 85F and 90%RH.

[Trace Beard]

Epifanes makes the house brand for West Marine, you may be able to save some money.

This is from the West Marine website.

Combines the finest ingredients for top-flight results
Made exclusively for West Marine by Epifanes, our Five Star Premium Varnish flows on easily and creates a coating with excellent flexibility and water resistance in all climates. Formulated with a high solids content, the finest Chinese tung oil, non-yellowing resins, and UV filters, this high-build, traditional spar varnish
Recommended Usage: Exterior or interior, above water
Formulation: Traditional alkyd, 64% solids
Additives: UV inhibitors
Recommended Usage: Exterior or interior, above water
Drying Time: Tack free: 4 hrs.; overcoat: 24 hrs. @ 65°F 65%RH
Number of coats recommended: Bare wood: 7 or 8 coats
Color: Clear amber
Finish: Gloss
Coverage: 150 to 300 sq.ft/liter
Thinner: Brush: Model 103731

Trace

[Wayne Watling]

I had very good results on my exterior mahogany entry way and door using Pettits Captain Spar Varnish. Its lasted four years without a scratch in the Canadian freeze and thaw cycle facing in the worst possible direction. From memory I layed down about 6 coats using a good quality varnish brush and had no problem with marks. Just be careful if you varnish anything that is standing vertical, its easy to get runs. The finish does have a very glossy appearence and you would have to dull it down if you wanted the satin look.

W.

[Steve Schoene]

Since Epifanes uses a phenolic alkyd combination for the resin, the West Marine product, which uses all alkyd resin, isn't just repackaged Epifanes. I don't think it has tested as well either in the periodic Practical Sailor tests. There is no free lunch.

[Steve Schoene]

Rat--we got snow today.