How to protect the hull after drilling holes for carrying handles?

Hey all,

My Chesapeake 17 is getting ready to hit the water - last coat of varnish should go on today, one more coat of hull paint this week, and then outfitting and I'm floating.

I have two more questions I'm hoping somebody can help with:

  - I want to drill holes through my endpours for carrying handles, but if I do this I'll obviously leave an edge of plywood bare to the water, which I don't want.  How do folks address this?  I'm a little worries I can't be accurate enough with the drill to do the drill/fill/drill solution.  I've also read something about fitting PVC pipe through the hole?!?  Any ideas? Help!


 - For the deck fittings, I've been told to put a dab of sealant in each pre-drilled hole before putting the screw in.  Are there guidelines for what type of sealant?  Would any old silicone caulk do?



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RE: How to protect the hull after drilling holes for carrying handles?

Hi Max,

on the end pours, the quick and easy way would be to drill your hole and soak the exposed wood in the hole with wet epoxy and that should protect it.  i have used that technique with no problem.  i used a q-tip soaked in epoxy to 'paint' the inside of the hole a couple times. to ensure it was sealed.

i have also done the end-pours with drill/fill/drill technique.  the secret to that approach is to drill a pilot hole (or series of pilot holes getting bigger and bigger) with a smaller bit building up to the size you finalize at.  this gives a lot of control and can allow you the precision you need with drill-fill-drill where you want the hole before drill/fill/drill to be about 1/4 inch wider than the final hole to give you a nice 1/8 margin all the way around.

also for drilling end-pour holes (either simple or drill/fill/drill) you will minimize damage potential to the hull by putting the first pilot hole all the way through (with the small bit) but then as you work up, you drill only into the hull ( a little more than half-way) from each side.  this avoids tear out.  the pilot hole ensures your drilling from oposite directions will meet in the middle.

with respect to the screw holes, to ensure the wood stays dry i use the following technique with excellent results. 1) drill the pilot hole for the screw, 2) put the screw in and screw it in then back it out (this taps the hole), 3) put a couple drops of epoxy into the hole (you can use a toothpick or bamboo skewer dipped in epoxy then dipped into the screw hole), 4) put the screw back in, drive it in then back it out.   this basically coats the inside of the screw hole/threads with epoxy creating a water-proof barrier.

after the epoxy has dried, and when you are ready for the final screw attachment, coat the screw threads in clear silicone before driving it it.  my only advice on brands is to make sure you are really using silicone.  the brand is not particularly important.  but often there are things being sold in the same section that are not actually silicone


good luck



RE: How to protect the hull after drilling holes for carrying handles?

   Hey Howard, thanks for the tips!  Particularly the "start with the pilot hole and work up in bit size" trick - perhaps, using this, I may in fact try the drill/fill/drill technique.  I don't have the steadiest of hands/most accurate drill, but I think I might give it a shot with this technique.

One question, on the screw hole method you outlined - after putting a drop or two of epoxy in the screw hole and then putting the screw in and backing it out, do you need a new screw when you finally put it in as the original one is now coated in epoxy?

And now that I think about it, are you using straight epoxy, or epoxy thickened slightly with something?  I imagine if it's thickened slightly it's less likely to fall down to the bottom of the hole after you back the screw out...



RE: How to protect the hull after drilling holes for carrying handles?


in answer to your questions:

1) do you need a new screw?  No. You will be using unthickened epoxy in the hole and when you drive the screw in and back it out, the wood will wipe any significant excesss epoxy off of it in the process.  So all of this is done before the epoxy has cured.  if for some reason the screw comes out all wet or things get sloppy with the screw, wipe it down with white vinegar-soaked paper towel before it cures.  but you preserve the screw.

2)  do you thicken the epoxy?  No.  the idea here is to seal the wood from any moisture intrusion.  when you drill the hole you will be exposing end grain of the plywood and sheer clamp.  the end grain will 'drink up'  unthickened epoxy and when it cures, that end-grain will now be sealed.  if you thicken the epoxy, it will not as easily be taken up by the end-grain.  by driving the screw in-and backing it out after you put a couple drops of epoxy in the hole, any excess epoxy that is not taken into the end-grain, will come out of the top of the hole and you just wipe it away.  there is no space for the epoxy to collect inside of the hole when the screw is put in to go anywhere except into the end-grain (where it will stay) or forced back out the top and wiped.  think of it like pushing a piston into a cylinder to coat the sides of the cylinder.

one last idea for you.....on the drilling.  you can practice the technique above on a scrap block of wood....a 2X4 should be fine to sort out and get a sense of the pilot hole and drilling in from each side and what drill bits work.   the only other thing i tend to be cautious of is when i get into the larger bits, they can sometimes 'grab' the wood and be difficult to control.  so a couple test shots on a scrap piece of wood can help you refine and get comfortable with the process before doing it on your boat.  i find wood spade or paddle bits work well above a 1/4 inch and  tend to follow the pilot hole well have less of a tendency to grab than metal drill bits that are pretty common around the house.   that said, i will use a 1/8 working up to a 1/4 inch  metal drill bit for the initial pilot holes.

good luck


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