Installing NFM portlights(long).

[Ed Schenck]

I just finished the installation of one lonely 5x12 NFM bronze portlight. Do NOT undertake this project unless you possess a lot of time and patience. Actually one of the 7x14’s is in the hole but only screwed in place until I have time to drill the holes and caulk it. I used one entire tube of Life-Calk on the 5x12!But if you do decide to invest here is the rest of the story. The NFM 5x12’s fit pretty well for replacing the smaller ports. NFM’s instructions lay everything out except how to make the hole the right size. For the remaining three I will add a 1/4" inch thickness of plywood to the bottom of the hole between the two drains of the spigot. This will save caulk. You have to glass in a couple of pieces of wood anyway to fill in the drain cutouts for the original ports. The spigots for the forward ports should be 1.5 inch. You can only get 1” and 3/4" bronze bolts. The 3/4" bolts only catch about one thread so I will cut some 1” bolts to size. The 1” bolts are too long to clamp the 5x12 ports. The bolt size is dictated by the length of the boss that is on the outside frame. They are about 3/8” deep which requires countersinking the holes from the outside. I used two screws from the inside to hold the port in place. Then I drilled from the inside using the actual port as the template. Be sure to drill square to the frame so that the outside frame will line up. Then countersink from the outside. Now you are ready to see if the bolts all line up before you get caulk all over everything. Once you know that everything lines up you are ready to fill all the voids with caulk and bolt together. Bolt loosely until the caulk sets. Now tighten everything and you should have a good seal. I was advised to not try to clean anything until the caulk was set. The 7x14s are more of a hassle(is that possible?) because the hole is too long. Now they make a 7x15 but it’s too late. So I had to glass in an oddly shaped piece of plywood on each end. And the spigot drains will not fit until you cut an indentation for them. Naturally they don’t fall in the same place as the original drains. Those still have to be filled with a couple pieces of wood and epoxy. Since I am doing the epoxy work anyway I mix enough to seal the entire plywood edge of the holes. Otherwise the big ports go in just like the small ports. The spigots are 2" on the 7x14s because the cabin is thicker in the main salon. I’ll post some pictures of the next one.Now if you have read this far, still want new ports? I only spent the money because I really want to go offshore. Besides, my old Gray portlights are in poor shape. But they never leaked. Go figure.

 

[Steve Dion]

Post the pic on the HOW site.

Ed:I am really interested in seeing what this looks like. If you have time could you post the pictures here so we can admire your project!?

 

[Thad]

how did you choose NFM

Ed, how did you decide on the NFM as opposed to the SeaFit? Did you ever compare the two - I guess I'm wondering if the SeaFit might fit the original opening better and be less hassle to install, perhaps countering the installation difficulty. Glassing in plywood pieces is a bit intimidating to me and I would be concerned about the long term integrity of the project, especially for offshore use. Do you think it would have been easier to replace the 5x12 portlights with a larger size, like the 7x15, or perhaps a different manufacturer's option, like the Atlantic series, in a slightly larger size?

 

[Ed Schenck]

The why of NFM.

At the time I did the research I think price was the main ingredient. I cannot remember if I looked at SeaFit. I did visit several booths at various large boat shows like Annapolis. Unlike so many boat owners the cost of marine equipment really does matter to me. If I had it to do over I would still select NFM, it is a very substantial product. But I would opt for the 7x15 for the better fit. The 5x12s fit quite well, just a little too much space top to bottom. And if you have the cash the stainless will be less work keeping bright. Epoxy work really isn't too bad after you have practiced a bit. I like the fact that now my plywood framing is completely sealed. And it's actually more structurally sound than before. The frames of the NFM ports are big enough that they cover all of that work. Since these bolt through and actually clamp the two sides(instead of being screwed in) they are very strong. Good luck with your project.

 

[Jerry]

Rubber seal leak

Hi Ed, I have had NFM bronze ports in my '80 H37C for 3 years now and really like them. A couple started leaking around the rubber gasket and I found that wipeing them with a moist paper towel to clean them solved the problem. The NFM rep said putting a small amount of vaseline on the rubber will help the seal and keep you from having to tighten the hold down cams (or what ever they are called).Jerrys/v Makai

 

[Ed Schenck]

Thanx for the update Jerry.

I have wondered about the tension on the cams. Looks like the adjustment is at the top, on the hinge bolts. I'll call NFM and get their reading on seal leaks and tension.