drilling/plugging holes in verticals

[cditzen]

Hi there,

I need to add a couple of eyes to hook a teather into just outside the compnionway in the cockpit. So typically, I''d drill the hole, hollow out the balsa-core, fill with epoxy, redrill, and insert the hardware. However, I am stomped on how to accomplish this with the surface in this case being vertical instead of horizontal. I checked the sections where I''d like to drill, and they are balsa-cored. If anybody has done this before, I''d love to get a few pointers.

The only thing I''ve come up with is to not do the hollow/fill gig, but just drill a hole for the HW that slants upwards so as to discourage water from flowing in. Not sure about capillary action, though.

Thanx...Chris

[paulk]

If you mix in enough microballoons, the epoxy mixture should be stiff enough not to run out of the hollowed out area. You can also tape over the hole once it''s been filled to help ensure a smooth surface. Since it''s for a safety harness tether, you may also want to add a backing pad or plate to the inside.

[BenDaniels]

I''ve just dealt with this. 72 holes on the starboard side to hold two acrylic portlights to the exterior cabin structure. A learning process as I went...no doubt the forward portlight is better sealed than the aft one. I used West Epoxy but found that with two much filler, I could not inject it very well using their syringes. So, I ended up putting another small hole over the original bolt hole, and into the hollowed out area balsa core. This hole was then plugged with polyester resin and then gel-coated, after I had re-drilled the bolt hole and checked to see that the epoxy completely surrounded the new drille hole. No one who has seen it can tell the difference except that the new gel-coat material is glossier than the original interior coat; painted on, not a mold. Have not yet figured out how to lower the gloss on the new gel-coat. On the starboard side, which I am doing now, I am using polyester resin as the filler, not epoxy, and the process is going much faster.

The problem with using Polyester as the filler is that:1. it shrinks more on setup and so pulls away from the core leaving room for water to get to the surrounding core, 2. It does not actualy seal the wood, 3. it is far weaker than epoxy and so will shatter. I used polyester to replace the core in a high stessed area of a boat I owned some 13 years ago. Two years or so later the deck was crushed again and the hole was full of polyester chips.

Jeff