I have an old radison 12" with some substansal holes in it. The previous owner had just epoxied and fiber glass sheet backed the entire canoe (including the motor mount) which in the end made the canoe well over 60 lbs when it should top out around 30lbs. I am doing a COMPLETE tear down on it to get it back to it’s old self. The problem with fiber glass is that it is heavy and rather expensive and it delaminates over time and you have to do it all over again.
I was wondering if anyone had any thoughts on patching it. My current plan is to:
clean all the sites with damage
put a flexable, water proof patch (hippo patch or HD weather stripping on the inside and out
cut a piece of medium to heavy gauge galvanize steel and sandwich the patch
4.get a flexable marine liquid patch to seal all the edges
rivet the patch in place.
then I plan on putting a coat of paint (elastomeric) over the bottom to make it look pretty.
weld Do you know anyone who can help you MIG or TIG weld aluminum patches? It would be stronger, cleaner loooking and you would not have to worry about galvanic corrosion between the steel and aluminum.
advice from a certified welder Tig welding would be great. This would be my choice. It takes an expensive setup to do aluminum sheet properly. (AC, high frequency, preferably with a foot pedal)
Mig would be fine also if the person had the proper rig for aluminum. (you need a rig with the wire feeder in your hand)
Brazing an aluminum patch would work also, but it would be ugly.
All three are likely to give some warpage, but you are going to have to live with a little of that. It can be kept to a minimum with a little forethought on the welders part.
...... put all that effort , time and money into an old 12' "Radison" aluminum canoe intirely coated inside and out with glass cloth and a bunch of other problems ?? Doing a complete overhaul ??
You can get a nice used Radison or another simular model pretty cheap ya know .
Personally , I'd let it die where it is , I don't think it's worth all that effort .
Use the same amount of time and effort to earn a few more bucks and get a better canoe I would say ..
Your discription makes that old Radison sound like a bad story gone worse .
even if you go with plan “A”… …you want to use aluminum for the patch. If hard to find you could always use the lower section of an old storm door or inexpensive camping cookware.
If you go with pilotwingz’ suggestion don’t forget that hull would be worth $50. or more at today’s scrap prices, so deduct that off the cost of a replacement.
Old F&S magazine had an article on aluminum canoe hull repair. Cleaned up jagged edges of hole and cut an aluminum patch to overlap the hole. Used a marine sealant and then riveted with solid aluminum rivets which have a low profile vs pop rivets.
Do not use any metal but aluminum for the repair because of galvanic reaction between dissimilar metals.
Alternatively you can get by using JB Weld in conjunction with an aluminum patch. Use some rivets if you wish but you could get by with just JB.
If you drill out the hole to be perfectly round you can cut an inside patch the same size and epoxy that in for a really clean repair.
Epoxy bonds to aluminum You can do successful epoxy / glass cloth patches on aluminum. A weld would be best but a lot of welders don’t want to work on metal so thin, I used to have an aluminum boat that a weld shop would not do so I used epoxy.
The most important thing: Once the area is sanded clean, you mix your epoxy and wet sand the area using the mixed epoxy and wet & dry sandpaper rather than water. If you pre-sand only, aluminum oxidizes in minutes and can compromise the bond. Many people have failed adhesion problems like you because someone didn’t do it properly.