Riveted aluminum boat construction

[Shellback]

Anybody familiar with aluminum boat construction? I'd like to know if they use a sealer of some type on riveted hull seams. The reason I ask, is I'd like to have a patch welded to the hull, but it's close to a seam. Sure don't want to mess up a sealant if one is used.

[RYE]

Regardless of sealant probably your best fix for a thru hole is welding. I worked in aluminum construction for alot of years in the truck industry. The seams then were either foam taped between the layers or caulked, usually both. The company I worked for was Grummans who also built boats. I would suggest welding your hole than applying a thin bead of a good sealant on the outer seam as well as inner if you can access it. There will probably also be foam in the hull to contend with, prior to welding make sure that all combustibles are clear in the hull at the immediate area of the repair. Good luck with your fix.....

[jimski2]

I had an old Starcraft 21 footer that leaked. After pulling the floorboards, I filled her up with some water. Water was weeping from many places. I chiseled off the old rivets, picked up new larger rivets. I drilled out the old holes to fit the new rivets. I made a piece of steel up with a hole drilled in it to receive the tail of the rivet.With a helper we pounded the aluminum to tighten up the rivet so it would not spin in its hole. Then we peened it over. I thought I would replace 12 rivets but when we were done, it was 268 rivets replaced. The boat was tight again but a couple years later the transom brace cracked and my outboard was flopping around. I gave up on the boat.

I bought a Lund, it was fine for 18 years but rivets leaked where the trailers roller bolt cracked and the hull had a dent. I now have a Crestliner welded aluminum hull, no rivets.

[RYE]

A word of caution, I would not attach steel to aluminum unless you use an anti-corrosion tape between the two metals. The aluminum will react with the steel causing it to corrode if you do not.

[rolmops]

I repaired some leaks in my 1961 Duratech (The same type as used by the CIA in the Bay Of Pigs incident) by getting an oversized piece of fairly heavy aluminum plating and instead of using rivets I used stainless steel truss headed phillips bolts with one side dipped in M5200 and on the inside of the boat nuts(with nylon inside)and washers.Using these bolts you can literally replace every rivet on your boat and repair every leak caused by old rivets.I squirted some M5200 on the plate that I "riveted" over the cracks and today 10 years later it still holds just fine.

[Shellback]

I repaired some leaks in my 1961 Duratech (The same type as used by the CIA in the Bay Of Pigs incident) by getting an oversized piece of fairly heavy aluminum plating and instead of using rivets I used stainless steel truss headed phillips bolts with one side dipped in M5200 and on the inside of the boat nuts(with nylon inside)and washers.Using these bolts you can literally replace every rivet on your boat and repair every leak caused by old rivets.I squirted some M5200 on the plate that I "riveted" over the cracks and today 10 years later it still holds just fine.

That is my other plan is welding isn't an option. Thanks

[Knotlost]

These can be easily fixed, if you don't try to do it cheap. You can buy heavy rivets, that are closed water tight rivets that you put in using the big rivet gun, It looks like a big pair of bolt cutters. Some of these rivets have a steel anvil so they are strong enough to pull the rivet, that's not a big deal as that is inside the rivet and is not against the boat or any other rivet and would take about 15 to 20 years to cause meaningful problems, and then you can replace it in about 70 seconds if and when it dose.

With these rivets you do want to use some good marine caulk and make sure the pieces are tight before you squeeze the rivet. The strength of these rivets are all rated so you can get what ever you feel is needed, but for a patch that's stronger than the surrounding it dose not have to be that heavy, look up the numbers. McMasters has lots of info. In the day we live now you don't have to make patches with blind rivets, they are better only if they are done perfectly. A good pop rivet in the right size is way better than a poorly done blind rivet.

I have seen some fishing boats that are pop riveted with beer cans and roofing tin over big holes, makes you shake your head and laugh, but I also have to admit they hold up and don't leak! Now I would not have done that but many people have with success. Its amazing what will work with aluminum, I do all mine by welding since I can and do weld aluminum but that's not always possible or needed with some problems.

They do not use a sealer for welding, as it would melt and burn, and contaminate the weld, they may have applied some sealer after it was welded, but not before. You would use sealer if your riveting. If its welded you have to be able to get both sides clean and keep them clean during welding or else your better off riveting it.

[Mickey Finn]

I don't know about the welding. I was told not to weld with a couple inches of the seam or the sealant would boil out and there would be a bigger problem. Maybe it's ok, but I'd check into it real good first.

[Knotlost]

No you can not weld close to anything that will contaminate the weld, there is not a "inch" rule, its simply your weld has to be impecably clean for good aluminum welding. When you get close to any junk on the metal your going to loose your flow.

[lilboat]

The Boatworks store in east syracuse recommended a product called Gluvit for some seal/rivet leaks.

I did and it worked on the Lilboat.

Its pretty easy to use too.

Good luck with your fix.

[rolmops]

The Boatworks store in east syracuse recommended a product called Gluvit for some seal/rivet leaks.

I did and it worked on the Lilboat.

Its pretty easy to use too.

Good luck with your fix.

I did some reading on Gluvit and I like the idea. Can you please describe how you used it and what problems, if any, you had while applying it?

Thanks,Cornelis.

[lilboat]

I did some reading on Gluvit and I like the idea. Can you please describe how you used it and what problems, if any, you had while applying it?

I used it for some minor seam and rivet leaks observed.

Filled the lilboat with H2O.

Marked source of any drips/leaks.

(Emptied H2O from lilboat)

Sanded/cleaned surface as best I could.

Mixed the 2 parts together in a disposable container per instructions/recipe.

I believe I applied 2 coats.

2nd one after the first is cured.

I never have tried to paint it, but I imaging one could,

Reminded me a little like fiber glass repair but without the cloth.

The stuff isn't cheap but appears to be worth it.

I also checked the internet for other's info as you are.

Good luck.

[DavidWP]

Might be a little late for the discussion, but there's a really good web site out there that is dedicated to aluminum boats www.tinboats.net. There's a ton of information on there for modifying and repairing aluminum boats.