Sliding hatch refinishing questions

[jordanbigel]

So, I need to refinish this sliding companionway hatch which was last refinished 21 years ago, at a yard in Seattle, when it was taken down to bare wood and sprayed with like 21 coats of AwlBrite Clear Gloss (a 2 part polyurethane). The aft edge with the handle started to fade around year 11. The cracking began around year 17 and progressed rapidly. Obviously I need to strip this all off and start over.

But I have some concerns because of the strips of black caulking which look like they might be some special kind of caulk, maybe like the one used in a teak deck?

I would be grateful for feedback from someone who has experience dealing with this kind of wood construction!

I'm wondering what is the best way to strip this down to bare wood without damaging these black stripes of caulk. I am reluctant to sand because how thick the coating is, I live aboard and the only place I have available to work as at the dock. So, I'm thinking heat gun and scraper. So what happens to those black stripes? The caulk appears to sit in grooves which could be about 1/4" deep, but a heat gun will probably melt it and ruin it.

Do I need to dig out the old caulk and re-caulk it? And if so, how do I prep the surface for coating - how do you get the caulk level with the wood so it can be coated? And what kind of caulk should I use?

In short, what is the best way to deal with these caulk stripes, other than paying a pro? I have lots of experience sanding and varnishing, but this has been my psychological white whale and I have been putting this off for years now because I am worried I will muck it up good.

Note: I am aware that there is discoloration of the teak in areas where the coating has completely cracked and broken off. I plan to treat it with a teak cleaner and however it comes out will have to be good enough, not looking for perfection. Blemishes are fine, I just want a solid coating which will last another 20 years (ok, maybe 15).

And if anyone tells me how I could have saved myself a lot of trouble if I had just re-coated it 10 years ago I am going to smash my computer with a ball peen hammer. Please. Don't.

Overall, I think the AwlBrite performed beautifully and except for the part which was damaged from UV, the rest of it looks almost perfect, as you can see, after over 2 decades! I am inclined to use the same product again, I may have to brush it on, but I may be able to get a friend to let me use his shop and sprayer. If not, it has to be brushed on. Is there a better product for this situation that is going to produce a hard finish that will last 10+ years without re-coating? If so, I would consider using it.

THANKS!

[tkeithlu]

Hmmmm. Doing this job without removing the hatch isn't likely to work. I suggest that you remove it and substitute whatever plywood or canvas cover will do while you rework it.

Looking carefully I think that I see the grain of the wood spanning the black stripes, such that they are decorative rather than caulking separate strips of wood. If that's the case, don't worry about them at this point - they can be replaced if you sand them away.

Getting all those layers of plastic off the wood is going to be a challenge. You may be able to pry some of it off - the varnish has separated from the wood, creating the problem in the first place. If you sand it off, be very careful. The wood may be softer than the varnish. On the other hand, removing it chemically would be a long and slow process.

[jordanbigel]

"Doing this job without removing the hatch isn't likely to work"

No, obviously not. I'm planning to do this on the dock.

"they are decorative rather than caulking separate strips of wood. "

Correct.

I'm leaning more toward a heat gun than chemicals. Maybe someone will step up who has worked with this kind of construction in the past, but if I do have to sand it, I may have to take it up to the parking lot and run the sander off my car battery, because if I create that much dust on the dock the dock master will notice (because he lives 3 boats down).

[Cheechako]

Originally Posted by jordanbigel

"Doing this job without removing the hatch isn't likely to work"

No, obviously not. I'm planning to do this on the dock.

"they are decorative rather than caulking separate strips of wood. "

Correct.

I'm leaning more toward a heat gun than chemicals. Maybe someone will step up who has worked with this kind of construction in the past, but if I do have to sand it, I may have to take it up to the parking lot and run the sander off my car battery, because if I create that much dust on the dock the dock master will notice (because he lives 3 boats down).

Yes, I'd go for the heat gun. If that was 2 part awlbrite, paint stripper may not touch it... not sure? The black caulk looks pretty good to me. The big milky finish failure is what happens a lot with 2 part finishes on wood and sun, but hey, 20 years up here is damn good!
If you sand the teak you likely wont need teak cleaner.

[jordanbigel]

Originally Posted by Cheechako

Yes, I'd go for the heat gun. If that was 2 part awlbrite, paint stripper may not touch it... not sure? The black caulk looks pretty good to me. The big milky finish failure is what happens a lot with 2 part finishes on wood and sun, but hey, 20 years up here is damn good!
If you sand the teak you likely wont need teak cleaner.

Thanks!

It's even more impressive because it was only 1 year in PNW then 6 years in the tropics followed by 14 years in SoCal.

[Cheechako]

Originally Posted by jordanbigel

Thanks!

It's even more impressive because it was only 1 year in PNW then 6 years in the tropics followed by 14 years in SoCal.

I think what saved much of it was simply having the dodger for blocking UV. Sunbrella covers on brightwork are true work saver...

[Beausoleil]

I'm in the middle of rebuilding and refinishing the teak hatches on my Formosa 51. They were made with teak framing, 1/4" plywood for the base and covered with strips of 1-7/8" x 1/2" teak decking - similar to yours.

The teak decking strips were down to 1/4" and the bungs were almost all gone. The plywood was rotted out.

What I did was replace the plywood with Lexan, and epoxied new teak decking to that. Instead of rubber caulk, I used epoxy with black pigment and colloidal silica as a thickening agent. I then coated with 4 coats of West System resin with their 207 special clear hardener. Now just to finish with a few (4-6?) coats of Bristol Finish 2-part epoxy with UV inhibitors.

I'm hoping that any differences in rate of expansion/contraction of the teak, lexan and epoxy aren't that great in a 25"x26" hatch, and a 36" x 30" companionway hatch. I didn't use any fasteners other than a few countersunk flat-head screws for the lexan - depending on the epoxy "bonding" to the 80-grit sanded lexan surface. I also used dowels to hold the trim pieces which run around the edge of the decking strips and the teak frame.

[psk125]

As Beausoleil suggests, the black seams in the hatch are likely some sort of inert filler. If they were Thiokol, Sikaflex or some other rubbery joint compound, they would not have been stable enough for the varnish to hold for more than a few seasons, if that. (Teak decks don't get varnished - they move too much.)

[jordanbigel]

Originally Posted by Beausoleil

I'm in the middle of rebuilding and refinishing the teak hatches on my Formosa 51.

Beautiful! When I am done with mine I will definitely post a photo. Thanks.

[jordanbigel]

Originally Posted by psk125

As Beausoleil suggests, the black seams in the hatch are likely some sort of inert filler. If they were Thiokol, Sikaflex or some other rubbery joint compound, they would not have been stable enough for the varnish to hold for more than a few seasons, if that. (Teak decks don't get varnished - they move too much.)

Good point. Thanks.

[Beausoleil]

I've been busy the past few weeks, and haven't yet applied the finish coats of Bristol Finish - will post pics when they're finished.

One thing I forgot to mention is that the inside of the hatch lid will be finished with white-tinted epoxy. I'll do a test to see if I should go with West 105/207 or with Bristol Finish. Since my B-F is the traditional amber, not clear - I'm afraid that it will have an off-white tint to it. West will probably look better, but I'm not sure how it will hold up to UV - it will still get exposure to the sun while at anchor ;-)

Or maybe I should just buy some Interlux 2-part paint? Sometimes using what you have on hand may not be the best choice...

Jordan: how are your hatch slides holding up?

On ours, the slides are the original bronze flat-bar, on the hatch sides and companionway - not the slickest transport around. Was thinking of replacing with starboard on the companionway rails, and stainless steel on the hatch itself. Starboard would hold up to UV better than nylon, and won't have any patina on the stainless. If anyone has a suggestion for something better, I'm all ears.

[jordanbigel]

Originally Posted by Beausoleil

Jordan: how are your hatch slides holding up?

Beautiful condition. The hatch has plastic strips the bottom on both sides which sit on a pair of stainless steel (polished) strips mounted to the boat. I guess I need to remove these plastic strips and re-attach them when I'm done.

[Beausoleil]

Originally Posted by jordanbigel

Beautiful condition. The hatch has plastic strips the bottom on both sides which sit on a pair of stainless steel (polished) strips mounted to the boat. I guess I need to remove these plastic strips and re-attach them when I'm done.

Great! So I was thinking correctly, then!

[Yojimbo]

I have absolutely no experience with these materials but want to ask: Would Soda Blasting work for removal without damaging the hatch?

[MarkSF]

I've had some experience removing varnish, and two methods that worked well for me were :

1) Heat gun, together with a carbide scraper. You want to pull the scraper rather than push, less chance of creating gouges in the wood. Still, I've had a couple of spots where a small chunk of wood lifted with the varnish.

2) "Safest Stripper" from 3M. It takes a while to work, but it does. Again, carbide scraper works well to lift the stubborn spots.

I'd advise against sanding. Tons of work, big mess.