Aluminum Canoe Rivet Repair

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Dec 2, 2016
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6
brace pulled away from hull above problem rivet. Rivet to right shows the brace is flush with ...PNG Arrow point to problem rivet.PNG

Hello fellow boaters,
I would like to generate a discussion on repairing my aluminum Grumman. It is 13 feet long, made in the 60's I think. I just bought it and do not want to get rid of it because for the first time I have a canoe that I can carry by myself. I also like it because I can leave it outdoors without worrying about UV problems etc. I have read many different opinions on this site and other sites, regarding the best way to make this repair. For example, stainless screws and nuts, aluminum welding, JB Weld, new rivets, duct tape, aluminum solder etc. The picture with the two arrows is from the inside of the boat and shows that the "cross brace" is no longer "flush" with the hull where the problem rivet is. I was able to slide the point of the orange arrows under the brace. Of the three rivet heads that you can see the one in the center is the problem. You can see the head of the problem rivet is still flush with the brace....but as I said..the brace is not flush with the hull. The second picture shows the "problem" rivet from the outside of the hull. This rivet is the leak that I have. I think if you click on the pictures they will become larger.
Looking forward to your help. This will be my winter project.
Thanks... John Boy the Canoe Boy
 

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Grandad

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Jun 7, 2011
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It's leaking because the rivet is gone. Why try anything other than replacing the rivet? If you don't feel capable of replacing a rivet yourself, get a repair shop to do it. If you still want to do it yourself, then you could use a stainless steel bolt and nut. I would apply a waterproof sealer and then replace the rivet after the sealer has a chance to creep into the crevice. Using only a sealer and not mechanically securing the join with a rivet or bolt will eventually allow it to leak again. - Grandad
 

ziggy

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Jun 30, 2004
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i've never done that repair, but just wanted to comment since yer a canoe'r.. ya need bondo to reply, he's got a gob of canoes. surely he knows the answer.
anyways.
looks like them is solid rivets.
here's a youtube on installing solid rivets. https://www.youtube.com/watch?v=xv2RBLPYikY
imho, that's what i'd be doing. in your case looks like the outside alum. is chamferd (counter sunk). looks like the counter sink is a bit buggered up. clean it up. ,i might also put some gluvit (an aluminium sealer is what i think this product is) i think its called prior to install of the rivot. then figure a way to install a solid rivet. if the bottom of the rivet is not flush, file it flush.

sorry about my uneducated guess, but i couldn't resist. i got me a plastic canoe 4 or so years ago. best 200 bucks i ever spent. i got what i think is a cool speed boat. i've been getting into the canoe thing so much that i went out 11 times in the speed boat and 22 times out canoeing last season. the peace and quite has really grabbed me and my 'ol lady... fix it and have a great time.... surely if my fix aint acceptable, someone who knows the facts will come by and correct me....
 

jbcurt00

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ziggy use

@Bondo

to notify him to check in @ this topic, just like I did you.

Chamfered solid rivets are available, but I'd drill out the old or simply knock the rivet head loose (shouldnt take much, half the rivet is missing) and install a brazier head, closed end blind rivet w a pop-rivet gun
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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I agree on the closed head rivet in the rivet gun with a bunch of 5200 in the hole first.
 

Bondo

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Ayuh,.... Welcome Aboard John Boy, 'n thank you for the vote of confidence Ziggy,...

All of my 100s of canoes have been Old Town's, 'n All plastic,...
But,.....
I have abit of experience with closed-end pop-rivets with my ole tin barge, a 1974 Starcraft Islander,....

I recommend ya go with all aluminum closed-end pop-rivets, the ones with the steel mandrel will work, 'n seal the hull, aluminum to aluminum, but the bit of mandrel left will rust, 'n stain things,....

I've plugged many missin' rivets in the ole tin barge with 3/16" all aluminum pop-rivets,....
A dab of sealant probably helps, but probably ain't necessary either,....
 

Watermann

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Welcome to iboats John Boy :wave:

I enjoy working with aluminum and have set hundreds of solid and blind rivets in older boats but never on a canoe. So I see you're dealing with some very thin material and bracing is very important to AL. You already have pretty much all of the options out there at least that I can think of. So I guess now you're seeking opinions. Mine is either solid or blind rivets.

Solid rivets are what the canoe was manufactured with and this is the most difficult / expensive way to repair a single or a few leaky or missing rivets. The solid rivets are cheap but everything that's needed to set them adds up quick.

The bottom of a canoe takes a serious beating as seem in the pic you posted with all the scratches. Repairing this with a blind rivet is an option. They also make countersunk closed end blind rivets but they're what I would think of as being a specialty and not found in too many stores, only online or in a fasteners store and then not an easy find. The countersunk heads I have aren't closed end but I don't use them below a waterline either.

fetch


I would recommend against putting anything there that is protruding above the surface to get caught, be sure it's countersunk in the hole. The easiest and least expensive way are blind rivets. You have to get the blinds in the correct length too, obviously too short would not be good but too long is an issue as well. That brings us to grip range of the blind rivet. You have to be in that range for the rivet to become tight and not have it loosen over time and for the mandrel to break correctly. It's really a guess but those look like 5/32" dia rivets. Also the degree of countersink, 120, 100, 78 is a guess? Blinds sold are normally 120 degree.

clsunk.gif
 

robert graham

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On my 1983 riveted aluminum canoe for occasional lost/loose rivets I've replaced them with a small(1/8-3/16 inch) Phillips head stainless machine screw and a Nyloc nut on the inside....easy and quick and so far no leaks or problems!.....For small leaks a blob of 3M Yellow Weatherstrip Adhesive is great!....
 
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Hi Bob....thanks for taking the time to help me out. You mentioned (1/8-3/16 inch) machine screws. Do you mean that you might find that in some cases you need 1/8" and in others 3/16"?. Also, how tight a fit do you try to get between your drilled out hole and the edges of the hull? For example drill a 1/8" inch hole...but fill it with say a 5/32" machine screw? Also...could you see from my picture that the "Cross Brace" is no longer flush with the inside of the hull where the problem rivet is? My question is...in your experience....will the screw and nut pull the brace flush with the hull?

Another question....I have noticed that some people leaving posts regarding this type of question, mention a reaction between aluminum and stainless. Have you see this in your experience? Thanks again.
John
 

robert graham

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A screw large enough to fill the hole left by the lost rivet.....usually about 1/8 inch or so....you can snug down that Nyloc nut to draw the pieces together....a small stainless fender washer could be helpful under the nut and/or screw head......Ace Hardware carries a great selection of stainless fasteners....No problem with the dissimilar metals in 20+ years so far....
 
Joined
Dec 2, 2016
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Hi Waterman,
Thank you for your reply. I am not familiar with this whole process...i.e. rivets...and the many different aspects to be considered. I have learned a lot just by reading your reply. I am not afraid of attempting something new....but I can see now that even though the job looks simple....there is a lot of homework to be done ahead of time, if your a novice like myself.

Mr first question is in regards to grip range. I assume that in order to determine grip range...I need to get a pretty close measure of the "hull thickness" PLUS the thickness of the cross brace I "pictured" on the inside of the hull. The schematic that you included looks very interesting to me and I think that perhaps I need to see the rest of the document that the schematic came with. Could you tell me where it is from? I think I need to find "basic riveting" information and perhaps that document could be good place to start learning the terminology necessary for this job.

I don't see this canoe repair as a big job...just one that I want to get right the first time. I feel that I have all winter to learn how....and then get it right with what looks like might be only thirty minutes of work.
Thanks.
John
 

Watermann

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I normally post a link to the info I'm posting, here is where I got the above image and where I buy most of my rivets online.
http://rivetsonline.com/rivets-en/bl...nd-rivets.html

The problem I have with SS machine screws is finding one that will be properly countersunk and would be flush with the bottom. If you can find a size that works then the screw with nyloc nut with 5200 to seal the water out is a viable option for repairing your canoes leaky rivets. If the SS screw head protrudes the risk is that it catches on something and rips out creating a larger hole in the bottom as the SS is considerably stronger than the thin AL around it.

All that being said, I have all the equipment to set solid rivets so that would be my first choice on the repairs.
 
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