Spray-on Hull Sealant?

[nemosuit]

You've probably seen ads on TV for a spray-on sealant; looks like that stuff they line truck beds with; supposedly seals leaky gutters and downspouts, etc. About the size of a tall spray-paint can.

In the TV ad, they cut a hole in the bottom of an aluminum canoe; install a screen door; and seal it with the black goo from the hairspray can. Then they take the boat out on the water, "and looka Luigi, she's-a no leaky!"

Anyway, knowing full well most of the stuff on TV is garbage; and the old rule about it looking too good...

What do you guys think about using that sort of stuff to reinforce leak-prone areas, like where the cab meets the hull?

VBR,

Pat

 

[Sumner]

Personally I'd never use something like that. I can't imagine the mess it would be to remove it if needed. You shouldn't have leaks in those areas and if you do I'd pick an appropriate 3M product.

I've seen the commercial and commented on it the other day to Ruth. The next time you see it watch as they spray the screen door. At the rate of spray I'll bet it would take tons of those cans and time to actually spray that whole door and make it waterproof. Notice they aren't spraying with the distance and speed that you would normally spray with rattle-can paint.

We had a few leaks around the chain plates and windows and I did a temp fix over a year ago in about 10 minutes with 3M4000 and they still have not leaked a drop since. I didn't take anything apart, just wiped it down as good as I could and put on a small bead and smoothed it with my finger wiped off the excess.

Are you finding time yet to work on the boat, hope so,

Sum

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[Capchas]

I don't get it!

Is the hull cracked and leaking? Just don't get it! There should be no need to seal a hull. If it leaks, you have BIG problems and should locate source and repair ASAP!

 

[timebandit]

I bet you could do the same thing with wheel bearings grease.

 

[nemosuit]

I bet you could do the same thing with wheel bearings grease.

The screen door trick? Probably right.

Thanks for the input, guys. Your thoughts are all pretty much my own. Always nice to have corroboration, though.

 

[rgranger]

Hey Nemosuit:

You and I are both working on a V22. And it occurred to me that you might not have this book. It is called

Don Casey's Complete Illustrated Sailboat Maintenance Manual

It is great. The best part is the ILLUSTRATED part. Anyway in his second chapter (Hull and Deck Repairs) he talks about running down leaks and how best to fix them... and also what not to do and why.

I have found this book to be an invaluable source of detailed info.

ISBN: 978-0-07-146284-6

Retails for $60. Would make a nice stocking stuffer

 

[JasonC]

I carry two cans on the boat.

 

[old guys sail]

shouldnt leak?

Is the hull cracked and leaking? Just don't get it! There should be no need to seal a hull. If it leaks, you have BIG problems and should locate source and repair ASAP!

CAp--my rub rail doesnt fit too well in places, and I can easlily remove it and the joining of the cabin/hull looks suspect. I imagine the rub rail itself, instead of diverting water, traps rain water under it and it leaks down inside hull (I have observed some of this.) Now you say I have a BIG problem? Bigger than removing the rail, epoxying the "joining", cleaning the inside of the rail real good and re-installing it?

 

[seaStan]

I've seen the ad and thought it might be good to have in an emergency but the stuff looks really rough and it could cause some serious drag while sailing and might provide a good surface for kinds of stuff to grow on (more drag). I would only consider it for emergency use.

 

[Snowypass]

I have a 1970 Catalina C22 serial number 150 that is a generation 1 swing keel. The keel is mounted with a boat that passes from the interior through the trunk, through the keel and back through the trunk under the seat. Sealing the the 2 interior pass throughs is not an easy chore. I took 2 short pieces of 2" pvc and filled them with modeling clay. I then pressed them over the bolt head and the nut. I then used the tv spray sealant to coat and seal the plugs. The product flows well, seals tight and smooth and is paintable. This reduces the need to sand and smooth.
Another excellent product for filling gouges and abrasions as well as an adhesive to bond other fiberglass pieces is "Vette Panel Adhesive" by Evercoat. It is very strong, water resistant and sands like fiberglass preventing undercut.

 

[finding41]

I think you can still get the rub rail extrusion at a half decent price. I have seen it in one of the Mac forums. Sorry I have no idea which one.
I was power washing the inside of my 26D on Thursday. (You know, just for fun, and to see if I how long could drag my sore back around until I could see my chiropractor.) I was washing the mud off the deck at the end and decided to hit the rub rail... Wow I didn't think they could hold so much YUCK (green and black stuff). I found that they hold water too and it runs down to the lowest part and leaks into the boat. Great another project! I have to get some of that butyl stuff.

 

[Hollyweirdos]

It sounds painfully familiar. That is how I found the leaks on mine. If you decide to remove the rail, the sealant holding the top to the bottom will be gone. The two halves will literally fall apart. Then it's game on!

 

[nemosuit]

Ahhhh...an old thread is revised, I see.

While working on our interior, I thought about spraying the stuff into the joint where the tub meets the roof: as a pro-active stopgap measure before installing a wooden trim moulding strip.

After surveying the responses it seems: (1) unnecessary; and (2) if I was going to do it, there are probably better sealants around.

Probably a pretty good bottom-paint for my screen-door canoe, though.

 

[redhead78]

Grt hold of yourself and think about what u are considering, do not waste your monay....Red

 

[nemosuit]

Grt hold of yourself and think about what u are considering, do not waste your monay....Red

Oh, I don't know. A screen-door canoe would probably be pretty cool.