How accurate does one have to be when measuring Gray Enterprises portlights for replacement?

[limbodog]

I'm intimidated by this job, because I'm worried I'll get the old one off and the new one won't fit and then I'll be trying to scramble to find one that fits and get it delivered while my portlight is wide open, it's going to get colder, and the vampires can get in.

So yeah, I have a 1985 Hunter 40. They were made using Gray Enterprises portlights. (you probably knew this)

The website says to measure the outside of the lens from side to side to determine its size. https://shop.sailboatowners.com/gray.php
I did so, and I get 14 and 13/16ths inches (possibly 7/8ths of an inch)

When I look up the sizes (also on the above link) I see "414" which is Lens dimensions 14-1/2 inch which is smaller, or "715" Lens dimensions 15-5/8 inch which is larger.

The size "715" goes into 8ths of an inch (others go to the 16th), so it's not like the 14 1/2 inch was just a rough estimate. I'm also assuming that they get down to the 16ths because they don't allow much wiggle room.

But having never done this, does that mean I need to buy a larger size and dremel the openings to fit a 15 5/8ths " portlight? Or can I buy one that is slightly smaller by 5/16ths of an inch and it won't have a gap through which the vampires can get in?

Or should I switch brands to one that will fit without having to do fiberglass surgery?

 

[dlochner]

The lens, the part of the port you see through is 14 ½" the extra is frame. I say this without having seen this particular port up close and personal. To be certain, call the SBO store and talk to Al, he'll know. Be a bit patient, SBO is a very small company and has few employees doing all the work.

 

[kloudie1]

I happen to have a 512 here.. Measuring the lens itself, it is 5 3/4" wide and 12 11/16 long
The 414 lens measures 4 5/8" wide and 14 9/16" long.. My '85 H-34 has 6 of the 512's and three of the 414's.
Looks like you have the one I don't have.

 

[Stu Jackson]

Or should I switch brands to one that will fit without having to do fiberglass surgery?

If you are definitely sure they are Grey portlights then do not change brands.

Look, it is a lot simpler than you are making it. Any and all companies that make portlights (Grey, Lewmar, Beckson, etc.) make a small handful of sizes. That's all, nothing in between. Each of their websites explains how to measure their own portlights, so you can confidently order replacements.

I had exactly the issue you have, but it was 27 years ago, before the internet. I got on the telephone (remember that tool?!? ) and called my manufacturer, Beckson, and asked them. They explained it and mailed me their brochure, sizing manuals and installation guide, which arrived a few days later. I read it and realized that I was making a simple task much harder than it really was. You already have all that info.

Good luck, you'll figure it out.

 

[Allan12210]

My 1985 34 of the same vintage as yours also came with the Gray Enterprises Portlights. They were the same size as @kloudie1 has described. I decided to upgrade mine to the Beckson. The openings cut into the cabin top had a bit of margin, but not a lot. The flanges on both sides cover the holes. It took a bit more effort than I expected. Be patient. I did have some water intrusion on a couple that required me to dig out the rotten plywood core material and fill it with thickened epoxy. Also I discovered that the inner liner was not adhered to the plywood core. That was only bonded to the exterior skin. I chose to fill that gap with pieces of cedar shims (available at Home Depot) saturated in epoxy. Then I coated the plywood edge of the cut with more epoxy. Also, the rain drains were in slightly different places so I had to fill the old cut outs and cut new ones. You may have to trim the extension for an even reveal to what you already have. I used an oscillating multi tool with a block of wood for the proper distance. Maybe these pictures can help a little. Good luck.