Fillling holes in thin aluminum?

Hey Guys,
I'm working on rebuilding my 22', '74 Starcraft aluminum boat.
It was originally set up as a ski boat and had all kinds of hardware drilled and mounted all over the gunwales.
I would like to remove all of this "junk" (I'm a fly fishing guy)but that will leave holes everywhere.
The aluminum gunwales are remarkably thin aluminum, maybe 1/8" if that (I'm know engineer so I won't try to figure out where they gain so much strength but they are very strong to walk on).
How can I fill all these holes once I remove the hardware?
Will I need to put wood on the underside to support the "fill" and keep it from flexing?
I'm a wood guy and know very little (read "nothing") regarding working with aluminum.
The gunwales are approximately seven" wide.

Thanks,
Gregg

Re: Fillling holes in thin aluminum?

duct tape underside, fill and sand JB weld.

Re: Fillling holes in thin aluminum?

The downside to patching the holes with epoxy is that the patches run the risk of popping open when flexed. You might step on the rail and un-do a great deal of work.

You could fill the holes with rivets and buck them in and you will have a bunch of rounded bumps up top....... or you can even go all out and have the holes filled by a welder who is good with aluminum. I have used a wire feed to weld holes up on a car body and sanded them smooth.

Re: Fillling holes in thin aluminum?

So, if I read this right the top of the gunnals on your boat are 7'' wide and there are holes you wnat to fill.

If it isn't below the water line, as TD said, put some tape on the bottom of the hole and fill then with JB Weld(It is runny when mixxed and needs a backer) let it dry, sand and paint.

That part of the boat doesn't flex much so it shouldn't pop out, just make sure you scuff the area really well first.

Most aluminum boat hulls are that thin, ribs, the floor and the floor supports are where the boat gets its strength, that is why you can't cut the seats out of a small tinny, it take out all the torsional support.

Re: Fillling holes in thin aluminum?

5150,
You read correctly.
All though there are no holes to fill at the moment, there sure will be by the time I remove all the hardware associated with the canvas top, snaps for the original factory cover, cleats, etc.
Thanks guys for the info.

Gregg

Re: Fillling holes in thin aluminum?

I would just pull the hardware , and use round head (stainlees steel ..) or , button head , machine screws to fill the holes .
If you have a need to mount something later , just unbolt and use the existing hole .

If you are picky about it , you can paint the bolt heads prior to installing .

JMO .

Re: Fillling holes in thin aluminum?

Something to remember if you use JB and sand, you will undoubtedly break through the paint as you are sanding, make sure you use etching primer on any bare aluminum before you paint it.

You Can get it at any auto parts store.

Re: Fillling holes in thin aluminum?

I would take it to a local welder. Save some money and grind it out yourself. If you do it well you'll never know it was touched. A bottle of crown usually pays for most of the work I have done on my boat.

I still swear hes got the best bar in town that welds!

Re: Fillling holes in thin aluminum?

have it tigged

Re: Fillling holes in thin aluminum?

I am very familiar with that hull, I own 5 myself at present and have had more than a dozen over the years.
I've seen several cures for beat up or well drilled gunwales. I've seen several done over in Nautolex, a few with matching carpet, and a few with rubber glued down. I did one myself by filling the holes and then using spray on bed liner tinted to match to fill or hide the repair. The result with any of these is a functional stepping surface as well.
These are tough hulls and they made this style boat for many, many years. They began in the early 60's and ran into the 1990's with variations of this hull.

I would venture to guess it has to be one of the most numerous production runs of all time when it comes to aluminum boats. I'd love to see the actual numbers on how many of these style hulls Starcraft built.