Question about drilling new cockpit drains

souljour2000 · #1 (**permalink**) 08-26-2008

I am widening my Hunter 20 cockpit drains from 1/2 inch to 1 inch or 1 1/4 . I am wondering if there is a way to keep the "bottom" of my current hole when I am drilling out the new hole if you follow.I dont want to widen the hole down at all but only up and out to the sides so I don't have water coming in more than It should on windy days. I am trying to think how to pilot the hole without slipping and while keeping the new hole where I want it.. Does anyone know of a jig system or some other way to achieve this? Thanks....

newpbs · #2 (**permalink**) 08-26-2008

I'm not sure that I follow you but I will give it a try. It sounds like you are working above the waterline and that you want to use a hole saw to make a larger hole in your hull. In that case I can see the need to have some material to hold the pilot drill while you operate the hole saw. If this is the case I would fashion a shallow wooden plug to fit the existing hole. Give the plug a little taper so that it fits snug in the hole and drill out the new opening accordingly.

Another approach would be to use a course rasp to widen the hole to the required size.

BTW, if you are working below the waterline...good luck.

Paul

souljour2000 · #3 (**permalink**) 08-26-2008

The plug suggestion sounds like it could work well..thanks for the help!

imagine2frolic · #4 (**permalink**) 08-26-2008

Mark the cockpit floor, and use a dremmel, or a larger sanding roll for a drill. It will work quick, and clean. Dusty as hell, but the hole will be clean....GOT A STEADY HAND?

sailingdog · #5 (**permalink**) 08-26-2008

The other way to do it is to tape or screw a board over the area you're planning on drilling the larger hole... and that will allow the hole saw arbor to have something to bite and keep the hole saw centered. I've used this technique for doors, through-hulls, and solar ventilators.

Maddog046 · #6 (**permalink**) 08-26-2008

This is easy, place a .5" and 1.5" hole saw on the same drill chuck. The .5" saw will center the 1.5" hole saw and you are good.

sailingdog · #7 (**permalink**) 08-26-2008

Actually, this is a horrible idea, since the OP wants to enlarge the existing hole asymetrically.... so that he doesn't cut andy further down into the cockpit floor. It would help if you actually read what the OP wrote...

Quote:

Originally Posted by souljour2000

I am widening my Hunter 20 cockpit drains from 1/2 inch to 1 inch or 1 1/4 . I am wondering if there is a way to keep the "bottom" of my current hole when I am drilling out the new hole if you follow.I don't want to widen the hole down at all but only up and out to the sides so I don't have water coming in more than It should on windy days.

Quote:

Originally Posted by Maddog046

This is easy, place a .5" and 1.5" hole saw on the same drill chuck. The .5" saw will center the 1.5" hole saw and you are good.

RXBOT · #8 (**permalink**) 08-26-2008

Is there such a thing as a !/2 holesaw .the smallest holesaw I'm aware of is 3/4 inch. But the idea is good and you could drill a 3/4 inch hole using a solid drill with turned down shank and use 3/4 inch holesaw and a larger holesaw as suggested.

souljour2000 · #9 (**permalink**) 08-26-2008

thanks for all the input everyone! Holesaw seems like a good way to go.I am itching to do this but havent put the boat in the water yet..When I do maybe I can simulate a large amount of water in the cockpit and see what gives...it is just that 1/2 " is so obviously small I am tempted to do the hole before I even test the cockpit...hmm..I am just not sure where the waterline is gonna be with this thing so better play it safe...and wait till later to drill these holes I know I am gonna drill anyways...lol

sailaway21 · #10 (**permalink**) 08-26-2008

You can also enlarge a hole in fiberglas with an electrician's reamer which is designed to be used on junction boxes and the like. It'll chuck in your drill and will allow you to progressively widen the hole to size. Home Depot carries them in the electrical department. If you want to open the hole off to the side you'll probably find that a Dremel tool or a Rotozip will do the job quite well using a dry wall cutting bit. I prefer the Dremel myself for it's versatility and the Rotozip drywall bits will fit it. Again, available at Home Marina.

Lighten up Dog, I had a bit of trouble cottoning on to the OP as well. and you just layed into a member with only five posts who might have been under the impression we're friendly here. (g)