3M 5200 (IMHO)

[RBEmerson]

Take a look at the number of boats built with 5200 used to caulk the hull/deck seam, for starters.

Also, how much flexibility are you looking for?

[sandy daugherty]

Here is an apocryphal story, attributed to a Marine Surveyor in Florida. He saw three boat yard workers laughing themselves silly, and asked to hear their story. Their job was to remove an aluminum dual outboard engine mount from the back of a sport fishing boat, and discovered it had been in use for two years hanging on the boat with three bolts and some 5200. Provide your own punch line.

[roverhi]

I have a question about how you are using the sealant. If you are laying it down next to an already inplace fixture like a toe rail, you are doomed to failure. Have never seen any attempt to seal like this work for the long haul, no matter what the sealant. You are asking too much of the sealant. If it's a leaking toe rail or deck joint, you may have to pull the rail or pop the deck and reseal with the sealant sandwiched between the parts.

I'm not personally fond of most 3m sealants. Find they are harder to work with than polysulfides (LifeCaulk or 3m 101), and go off very quickly in the tube after it's opened. I've been using LifeCaulk since I got into boating and it's the only caulk I've been happy with.

5200 might be good if you are looking more for an adhesive than a caulk. Have heard it works very well on through deck chainplates where other sealants haven't from a number of sources.

For the guy who is happy with sillycone, my condolences. You WILL suffer through the error of your ways.

Aloha
Peter O.
Pearson 35

[RBEmerson]

[/ROFL] Hey, at least there were no nuts to worry about losing...

[Cheechako]

5200? Dont leave home without it!

[roverhi]

I don't understand your problem. Did you break the tip off your rudder and are bonding a new tip to the bottom of the rudder?? It that is the case, doubt that gluing it on with 5200 would work but then 5200 has a reputation as a ferocious bonding agent. If you could insert a in a pin(s) into the new tip and into the rudder might have more faith in its long term viability. Best thing would be to a FRP wrap around the joint and fair it in.

If this is another type of repair, explain more fully.

Aloha
Peter O.

[Firehoser75]

I don't want to hijack this thread, but am looking for some advise. My keel attaches right at the hull (in other words there is no keel stub). The sealant/caulking material is now showing signs of minor cracking. Once I remove the cracking material, what sealant should I use. 5200? 4200? Polysulphides like sikaflex?
Thanks,
Tom

[Cheechako]

You could use 5200, but if you are just sealing and not needing any bonding strength, probably 3M 101 polysulphide would be great. It can be launched wet. If you want to sand it after applying, then 5200 would be better, but will take a while to get hard enough to sand

[s/v Jedi]

Steve Dashew calculated that 5200 alone would be enough to stick a keel under a Sundeer. The only trouble would be when hitting the bottom or a rock or something, so he put keel bolts in anyway (phew!!).

But this just shows that the 5200 product is a great product. It is the user going wrong when selecting it for a job that it isn't suitable for.

And for thru hulls it isn't really a problem to use 5200. The same size hole saw that was used for putting in the thru-hull fitting will easily cut it out again.

cheers,
Nick.

[SariTimur]

I use 5200 and am very happy with it. I use it for thru hulls, under cleats even under winch pads and lifeline stanchions. I used it 18 years ago when we had our cap rail demolished in a remote area. I could get wood but little else. Another Yachtie had several tubes of 5200 and suggested I use it. The boat did two Indian Ocean crossings and when I finally repaired the cap rail with the proper wood 10 years later found the seal still good and dry.

I learned a trick for taking off the fittings was to use a putty knife or paint scraper and a heat gun to get the bulk off or lift fittings then sand off the remainder. Also use mentholated spirits for clean up. It does not like direct sunlight. Can go gooey so for those conditions I use sikaflex DC.

[RBEmerson]

5200 can also be cut with thin wire used like a cheese slicer. There are 5200 removal sprays which, IMNSHO, are a waste of time and money. After spraying a 5200 installation with one, absolutely nothing happened. A wire and razor were far more effective.

Nonetheless, in general, do not use 5200 on something you have some hopes of removing at some point in the future. 4200 or other sealants are a better choice.