I proceeded with my plan it so far its worked perfectly.
I taped tight across the bottom of the hull.
Flipped the boat over, taped off carefully around the bailer holes
Then I took Aluminum Foil tape (the stuff used for HVAC ducting) and made a riser cylinder. I taped the riser to the previously taped perimiter around the hole with more masking tape.
I mixed 12g of West Systems 105 epoxy + 205 fast hardener and poured it in the riser. 12g was only enough to fill one riser flush with the hull, so I mexed 24g more epoxy and put half into the empty tube and double filled the other side, which had the significant cracks.
I let the epoxy heat up in the sub to aobut 70f, then let it sit in the cup for about 2 minutes before pouring in. When epoxy sits in the cup as a large mass with, low surface area it begins to heat up and cure very quyickly, due to its exothermic reaction. I intentionally let it heat up like this to speed its curing once poured, as even the fast hardner can be liquid for a half hour if its cool (<60f) and spread out (like when glassing fabric). I wanted it to cure fast.
I inhaled a half breath through the vent hole and epoxy rapidly sucked into the cracks. I saw it happen and relieved the slight negative pressure.
The epoxy continued to run in slowly over the next 5 minutes before it finally gel'd and quickly cured.
After about 10 minutes it had a hard crust and after about 30 minutes i sliced off the chimney left behind by the over-fill. at aobut 30mins in the direct sun it was fully hard, but not final-cure hard. I was able to cut through it with a thin utility knife. If it went any longer, it would have been impossible to cut through and would have required grinding, which is much tougher/more messy.
I let it cure in the sun for another hour. Then I took out my 1/2" counterbore bit and drilled a 1/2" pilot hole.
Next I used the dremel tool with coarse sandpaper to enlarge the hole so there was just a little epoxy left surrounding the enlarged hole, about 1mm / .050" per side.
Now Im letting the epoxy cure out fully. This evening I'll use some 1 minute epoxy to re-attach the venturi cones and take her for a spin tomorrow to see if she's finally water tight!
Overall this fix took 3-4 hours in all, but was not very hard. Hopefully this works as a long term fix. I'll report back as time goes on with the results
Current - Kai Wa'a Vega Flex & Swordfish S Carbon in Ventura County, CA
Past Boats: Epic V10g1, Stellar SRg1, Fenn XTg1, Swordfish S Glass
"When you've done something right, they wont know you've done anything at all"