Forward Hatch Replacement/Measurements on 42 Classic

[Rob R]

I need to replace the original Lewmar hatch on my 1988 GB 42 classic (its leaking and plexiglass is crazed). Unfortunately I don't have accurate measurements for the exterior hatch frame and I live 1,400 miles from my boat so....
Has anyone replaced their hatch? If so what size Lewmar, Vetus or Bomar did you use and was it a perfect fit?
I believe GB used the Lewmar Trimline or Rollstop model hatch (produced from 1986-99) so ideally any GB 42 classic in that range would have the same hatch size.
Thanks in advance for your replies and I'll post a write-up of the work at the end of the month when I get to the boat.

 

[Datenight]

You might want to try Hatch Masters in Norwalk, CT. https://hatchmasters.com/ They can rebuild your present hatch.

If you are a diy person, remove the hatch (heat gun and wood wedges help) and "glass". Have the frame sand blasted and powder coated and new glass from a local glass shop. This worked for me.

Rob

 

[BruceK]

Sometimes they leak because the seal around the "glass" has shrunk and separated where the ends joined. Careful masking and use of a good matching sealant can work wonders. It has for me, twice, on glass surround seals.

 

[Rob R]

Thanks for the suggestions on fixing the hatch. Unfortunately this hatch has issues with the plexiglass as well as frame. Its time to replace.
Anyone with access to their boat that could give me the outside frame dimensions (from topside)?
Later this month I'll fly out to my boat for 4 days or work. I'd love to get a hatch ordered prior to that.
Cheers, Rob

 

[firstbase]

Hi Rob. We are at the beginning of a tropical storm which will go through Sunday. I will be going to the boat to check and make sure all is well. When I do I will get you the exterior measurements.

 

[Rob R]

Thanks and best of luck with the storm, sounds like big flooding so far.

 

[firstbase]

The storm ended up being no big deal. Some good rain, a little wind... but nothing to write home about.

Here are the dimensions of my forward hatch. I took some other measurements such as the molded fiberglass base on the deck under the hatch, and the teak frame that the hatch rests on. If you need more than what is shown here just let me know. To make sure I was clear in the drawing, the 1-7/8" side measurement does not include the plexiglass that rests on the frame. It is just the frame itself.

 

[firstbase]

Forgot to mention..thanks for helping point out something I missed when varnishing. Just when I think I got it all under control....

 

[Rob R]

Hal, Thanks for the meticulous answer and picture. I had thought my hatch was original but obviously it was not being a Lewmar aluminum hatch. I've only owned the boat for a few months so lots to learn!
Rob

 

[firstbase]

Hal, Thanks for the meticulous answer and picture. I had thought my hatch was original but obviously it was not being a Lewmar aluminum hatch. I've only owned the boat for a few months so lots to learn!
Rob

You are welcome. I would want exacts if I were ordering a hatch without looking at my boat. I imagine that the base for the hatch, the base that is molded into the deck on an '86-'87 GB42, would be the same no matter which hatch was placed on it. I have those measurements as well if you need them.

I can't imagine living that far from my boat!!