Same boat and same hole in keel I was working on last month. Fiberglass Bondo and Silly Putty Epoxy do not work. So I got the fiberglass patch kit, sanded the thing pretty smooth ( almost impossible to do). Mixed the resin and hardener and soaked my cloth in it. Now comes the problem. The hole is in the bottom of the boat. I can't turn the boat upside down to work on it so I am attempting to place the patch over head. It kept falling down, so I used my hands to hold it in place till it cure a little and then smoothed all the bubbles out with my hands. What a gooey sticky mess, but I managed to get the first layer of mat on and also to get my hands cleaned off before they started to cure.
My question is: How long can I let the mat soak in the resin/hardener so that it will stick to the boat with out falling down?
Yes I am going to use rubber gloves when I apply the next layer.
Got enough mat to put on three layers, which i hope is sufficient.
The directions are a lot simpler than the actual job.

Take it to a metal welding shop and have it welded, it is worth the few bucks to have it fixed right then to fix it half a$$. Try a muffler shop they can normally weld aluminum, and don't charge too much. My dad paid $25 to have a couple of places on his welded that was about 12 inches long on both sides of the bottom, where the sides meet. It is a common place for them to bust loose especially in rought boating conditions.

Fiberglass on Aluminum, That is a billiant idea!

If you are trying to put your glass on upside down, then you have to turn the mat over and put it upside down, that way it matches the gravitational pull of the matt!

However, being in the business, I don't think it will last very long at all it it bonds at all. Take it in and have it welded. :whistle:

Grandpaw

You CAN successfully fiberglass over aluminum.. it's done on Aircraft every day... but you'll need some epoxy polymer resin. Boat resin wont stick well because it cures too fast and is not a structural epoxy adhesive.

Get you some "Neat Stuff" spray insulation foam. Clean off the inside and outside of the hull with Isopropyl Alcohol so you have a nice clean grease & oil free repair area that epoxy will adhere too well. Tape off the inside of the damaged area so the foam will have a barrier to form against.

Inject the damaged area with foam. When it cures shave it off level with the outside of the hull to give you a level surface to repair. Spread a thin coat of epoxy over the foam to seal it so it wont soak up your resin from your patch. Sand it smooth before applying the patch.

After you soak the 3 pieces of glass cloth with epoxy resin you'll need some clear plastic to cover the patch and tape to keep the plastic in place. Make sure to use plenty of resin so you dont have dry glass voids in your patch.

Set the the 3 pieces of resin soaked glass cloth on the plastic sheet with the largest piece first and the smallest last.. then tape the whole repair to the hull.

Get a plastic Bondo spreader and use that to comb out the air bubbles from the repair patch out toward the edges. You will need 3 layers of matting to do a good durable repair. Cut each added layer about 1/2" bigger than the first so you have a nice tapered edge on your repair that wont snag.

A heat lamp will aid your cure time and it should set up in about 1 1/2 to 2 hours depending on the epoxy used. Sand the excess adhesive off after the repair has hardened taking care not to expose the glass cloth. If you do get into the cloth you'll need to re-apply some resin and wait until it cures before getting the hull wet.

You will need to allow 24 hours for the repair to cure after the epoxy sets before getting the repair wet.

Or you could just skip all that Messy Stuff and have it welded!

Bazz

JB Weld won't work?

JB Weld will not work i have tryed it.. once it gets wet it falls apart! Just have it welded save you the trouble!

I am not advocatind half ars patching it, but I think JB weld will work. we used it to patch a hole in my budies radiator, and it held for over six months without leaking a drop, and that is hot water that is under presure.

matt