questions about installing portholes

[Fitz87]

I am about to finish painting and I had a couple of questions about getting my portholes back in. I remember reading several good threads on the subject here, but can't seem to find them now. So if these questions are answered somewhere else, please redirect me.

1. Should I sand or "rough up" the paint where the sealant will go? It's 2 part polyurethane paint and Dow 795 sealant.

2. I have plastic Beckson portholes and scraped all of the old sealant off, is there any other prep to do or just make sure they're clean?

3. Any tips on how not to make a huge mess of this project (as I am very skilled at making huge messes when it comes to caulk etc.!).

Thanks in advance.

[donlofland]

Expect a few opinions regarding avoiding the mess, and here's what I've settled on as a good technique-

See if you can hold the porthole/whatever in place, and mask around it. Also mask the porthole/piece.

Once the porthole/whatever is installed, take a popsickle stick and go around the porthole with a popsickle stick to remove the sealant that squished out, wiping off the popsickle stick with a paper towel frequently. Then remove the masking tape before the sealant begins to harden.

I rebedded the deadlights on my Catalina using a kit from Catalina Direct, with enclosed instructions. There was no mention there of roughing up before rebedding...

[mitiempo]

I agree about the masking. Roughing the surface isn't required but absolute cleanliness is. Even your fingerprints can leave enough oil on the surface to affect the adhesive. Best to clean mating surfaces with alcohol and wear gloves.

[bruceyp]

Take a look at Maine Sail's:
Installing New Found Metals Stainless Portlights Photo Gallery by Compass Marine at pbase.com
It is very informative.

[Cruisingdad]

You can also cut out the stuff after it has dried. I have done both. I think the masking first looks better, but that is my opinion.

Be aware that you have a 7 day cure on 795, and I would say about 24 hrs of no moisture. I would not take her sailing for a week after application. The flexing of the boat can cause it to fail.

Cleanup is with acetone. Be careful about acetone on the lexan... or whatever that stuff is made of. It will mar the plastic. I found that xylene does not (but check before you do it). I used acteone first, then Xylene. Xylene and toluene are good cleaners too, but very carcinogenic IMHO. You will need some type of special gove as most gloves disolve in them. It turned out better for me just to be really careful. Last caution is to make sure you keep her out of direct sunlight if possible. The heating of the plastic will make it warp very slightly and break the seal of the 795. I found this one out the hard way. I do not think it has to sit in in the shade all day... but the longer the better.

Sidenote is that I think you can also use alcohol to prep instead of acetone... but I keep so much acetone I used that.

Not a hard project, but working with 795 is like working with snot. Have fun and keep plenty of beer for afterwards.

Brian

[Fitz87]

Thanks very much to all of you for the advice. I'll let you know how it turns out. And thanks for the posting by Maine Sail, I had been trying to find that again.


Thanks again
Fitz

[Annapolisboater]

call us...use silproof, not in full sun & heat. Scrape all surfaces & wipe with alchohol. You should scribe a line of the hole from the inside, cut with a razor & remove the outside & paint w/flat blk paint - it will cover the sealant and give some nice bling. We use dbl foam tape to prevent the sealproof from going inside..and then fill in the outside with enough to make a nice dip-edge edge...MAKE sure to tape around both the exterior & interior of the port hole. It is 50% art, & 50% skillful science. Almost everyone who tries it....comes back & we go out to do it right.

Would you take you childs appendix out? Time to think if you can afford to go cheap. My friends says she is to poor to do things cheaply. My father asked me once:
What is the most expensive thing you can do?
Answer: buy or do something on the cheap. Just friendly advice.