Best way to seal holes/gaps in an aluminum hull?

gunner1

Petty Officer 1st Class
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May 13, 2006
Messages
375
Went to take my 1967 Starcraft aluminum hull boat out today and noticed water coming in from the rear transom area. When I got it home, I noticed some holes in the transom where it looks like some rivets are missing. What's the best way to fill/seal them? Also, I'd like to seal the seam that runs along both sides of the keel. Would 3M 5200 be good?
 

Shawn Acker

Cadet
Joined
Oct 1, 2007
Messages
16
Re: Best way to seal holes/gaps in an aluminum hull?

I personally would TIG weld it. are you around houston, texas anywhere.
I have a lummie to TIG up this weekend. You bring the beer ill bring out the welder.
 

gunner1

Petty Officer 1st Class
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May 13, 2006
Messages
375
Re: Best way to seal holes/gaps in an aluminum hull?

I personally would TIG weld it. are you around houston, texas anywhere.
I have a lummie to TIG up this weekend. You bring the beer ill bring out the welder.

Only if you consider New York close to Houston! Thanks for the offer though.
 

rolmops

Vice Admiral
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Feb 24, 2002
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5,299
Re: Best way to seal holes/gaps in an aluminum hull?

If you have a fastener store in your area yo may want to take them one of your rivets and ask them if they sell stainless steel truss headed phillips screws about half an inch to an inch longer than your rivets.The same thickness as your rivets of course.Get these with washers and nuts.These are not your local home depot product,you have to go to a place that specializes in fasteners.
once you have found them you can drill out all the loose rivets and replace them with your truss headed bolts that have the same shape as your rivets.In fact,you can replace every single rivet in your boat with them.It would of course be smart to get some marine sealant on the inside of the bolts.
 

tashasdaddy

Honorary Moderator Emeritus
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51,019
Re: Best way to seal holes/gaps in an aluminum hull?

stainless nut and bolt with rubber washers. if it was rivets missing they were holding something.
 

dimock44

Petty Officer 1st Class
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Sep 7, 2007
Messages
275
Re: Best way to seal holes/gaps in an aluminum hull?

3 m 5200 takes 7 day to cure and 2 day to tack over. I put it in the water after 2 days and it held. I keep my boats in a boat house and try to bring them up to the shop as little as possible. For quick repairs I use gutter seal. Holds pretty good and suprisingly is sort of gas resistant
 

Bob_VT

Moderator & Unofficial iBoats Historian
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Re: Best way to seal holes/gaps in an aluminum hull?

stainless nut and bolt with rubber washers. if it was rivets missing they were holding something.

Take that advice seriously...... I doubt random rivets are installed and you might even want to get some pop rives that fit the hole..... you can measure the length (grip depth) with a piece of wire. You really should make sure you are keeping things attached. You can put some 5200 on the rivet before you pop it and a dab over the head. It will last.
 

1730V

Chief Petty Officer
Joined
Feb 14, 2004
Messages
563
Re: Best way to seal holes/gaps in an aluminum hull?

If rivets are missing, they need to be replaced. You can use aluminum pop rivets. Make sure the aluminum rivets have aluminum centers-not steel.

Once riveted, the best sealer for aluminum boats, by far, is Gluv It. It is best applied from the inside of the boat.

Gluv It is available here on iboats.
 

iwombat

Captain
Joined
Jul 12, 2006
Messages
3,767
Re: Best way to seal holes/gaps in an aluminum hull?

You can use closed-end aluminum blind rivets to seal all that up. Make sure they have aluminum mandrels. A little marine-tex on the shaft doesn't hurt either.

Find a source online and order a big bag. That's not the last rivet your old tinny will pop, and it's good to have replacements on hand.
 

buckstop108

Seaman
Joined
Aug 2, 2007
Messages
67
Re: Best way to seal holes/gaps in an aluminum hull?

Not meaning to highjack this thread, but, What causes a rivet to pop? I have a 1992 Lund with carpeted decks and finished gunwhales if a rivet should pop I assume that I would have to take up the decks to make the repair and hope it is not in an area that they sprayed the foam. Is this correct? I am assuming that a rivet can not be repaired from the outside of the hull.
 

Shawn Acker

Cadet
Joined
Oct 1, 2007
Messages
16
Re: Best way to seal holes/gaps in an aluminum hull?

to answer the question you do want to put in the rivet from the outside. If you put it in from the inside it will not be flush.
Arlo
 

gunner1

Petty Officer 1st Class
Joined
May 13, 2006
Messages
375
Re: Best way to seal holes/gaps in an aluminum hull?

I have a pontoon that I used Alvin's Aluminum Bondo to repair the holes and all works great.

http://www.alvinproducts.com/Products/Content.asp?id=2

How would I best seal the holes using this? Could I put a piece of plywood behind it, spackle over the holes, let it cure, then remove the plywood sheet? Or would it be best to just stick some screws with sealant on them in the holes?
 

cuzzx

Seaman
Joined
Oct 14, 2007
Messages
74
Re: Best way to seal holes/gaps in an aluminum hull?

it works like bondo , just smooth it on the best you can, let dry then sand smooth.
 

reelfishin

Captain
Joined
Mar 19, 2007
Messages
3,043
Re: Best way to seal holes/gaps in an aluminum hull?

I've also used Marine Tex or several other aluminum filler type epoxies.
All work well but when it comes to missing rivets, I'd replace the rivets first.
 

AZMinyard

Petty Officer 2nd Class
Joined
Jun 26, 2008
Messages
165
Re: Best way to seal holes/gaps in an aluminum hull?

Take a look at the following thread:

http://forums.iboats.com/showthread.php?t=225499

"Mr.Stuart" used a aluminum welding product to fill holes/cracks with some fine results. I was able to find a similar product at Home Depot.

At any rate, it is a great thread and well worth reading!
 
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