How to Seal up to Bedliner (?)

[xymotic]

Hi everyone, I have a hatch in my steel boat. Structurally, it's a steel square welded to the deck. On both sides of the steel are pieces of Mahogany. The P.O. started work to replace the hatch, and it looked pretty good, but he used opaque fairing compound on it, I guess he was going to paint it rather than varnish.

But knowing his other work, I decided to tear into it a bit and see what was 'up' and boy am I glad I did!



Couple chunks of Mahogany screwed into the steel, a couple using brass flat-head screws. There was a little bit of epoxy holding stuff together, but no sealant, and a couple of bolts are completely rusted with a couple tiny spots of cancer starting.

OK< so here's my question, at the bottom of the boards on the deck side, there is almost 1/2" of what I thought was boatlife-type sealant. I ground it out about 2" thinking I'd fair that area with splash-zone and repaint the deck. hard to see in the above pic but it's the brownish area at the bottom of the hatch.

However the stuff never quit, and so I ground out a chunk under the propane locker a couple feet away and same stuff, so Now I'm thinking that this is actually a sprayed on truck bed liner type material, which has also been painted over.

so, um, now what? How do I seal this back up?

[boden36]

One of my basic rules with steel is never attach wood to it. It always causes trouble in the long run.
I would suggest you remove the boards, abrasive blast and coat the steel and leave it at that.
Regards,
Richard.

[xymotic]

Originally Posted by boden36

One of my basic rules with steel is never attach wood to it. It always causes trouble in the long run.
I would suggest you remove the boards, abrasive blast and coat the steel and leave it at that.
Regards,
Richard.

Well, I did think about that too. Once I got it cleaned up I admit I like the idea of just fairing it out and painting it.

But the hatch the PO got would be too big to fit just the steel, At the very least it would need a 1x2 or something trim piece around the top.

And I still need to pretty up the area where the deck bedliner comes up to the vertical steel of the hatch.

[xymotic]

Originally Posted by boden36

One of my basic rules with steel is never attach wood to it. It always causes trouble in the long run.
I would suggest you remove the boards, abrasive blast and coat the steel and leave it at that.
Regards,
Richard.

Ok, here's an update. I decided to pull the exterior wood and leave the interior, which was way stupid because I set it on a fire a couple times welding, and then decided I needed to get to it for other reasons and seal it better. SO take a lesson from me and pull the wood before you weld. Sure it seems obvious but well...

So I decided to remove the aft wood completely and replace it with steel.


But I still have the same problem. the screws in the hatch are just about perfectly aligned to the vertical steel, so there's just no way to screw it down. this pic shows the 'error' the other corner is lined up to the edge.



So I've thought of a couple ideas. I could weld on a 1/4" piece of steel, and then drill/tap it and attach the hatch straight to it.

I thought about having a 'ring' water cut to fit the hatch, and welding or riveting that on.

I could put on a top 'ring' of 1x2 teak or Mahogany and attach the hatch to that. this seems easiest, but I'm reluctant to go that route because I do tend to agree with Richard's comments.

OTOH, I think I really want "A" nice piece of mahogany on the boat. Given the boat's history and how damned nice this hatch is, it seems like a nice place to do it. But I'm torn because of above, and money is tight (I trashed most of the wood taking it off) and this seems the lease durable long term.

ANd lastly, even just straight steel it looks OK, I just still can't figgure out what to do about the top ring and the 'trench' I made in the bedliner. If I put wood sides back on, that 'trench' would be a little easier to hide, but then I think do I want to 'hide' a potential moisture spot?