Transducer Mounting-which bit to drill through the hull?

[NewfieDan]

I am booked for having some electronics mounted. The company specializes in Avaition or commercial boat electronics. As such, they won't drill a hole through my hull for the transducer. I can drill the hole.

My question is what type of bit do i use to prevent any splintering or chipping around the hole? I have a variety of bits. Everything from a shallow angle steel bit to wood brad point bits. Which is best?

 

[Thalasso]

Re: Transducer Mounting-which bit to drill through the hull?

I am booked for having some electronics mounted. The company specializes in Avaition or commercial boat electronics. As such, they won't drill a hole through my hull for the transducer. I can drill the hole.

My question is what type of bit do i use to prevent any splintering or chipping around the hole? I have a variety of bits. Everything from a shallow angle steel bit to wood brad point bits. Which is best?

Don't worry about any special bit. Before drilling,use the next size bit and reverse the direction of the drill.Almost like a touch and go, which isn't very much. This will keep the bit you are going to use for hole from grabbing and chipping the gelcoat. Then go ahead and drill your hole.

 

[coastalrichard]

Re: Transducer Mounting-which bit to drill through the hull?

Put a small piece of duct tape over the area you're drilling....no chipping!

 

[dingbat]

Re: Transducer Mounting-which bit to drill through the hull?

People recommend masking tape, running the drill in reverse, (I’m not sure how that is supposed to works) but I’ve always just used a center drill to get things started and went from there. When done, hit it with a 82 degree countersink to smooth out the edges

 

[jdlough]

Re: Transducer Mounting-which bit to drill through the hull?

A bit about twice the size of the hole you need, run in reverse, makes a fairly decent poor-man's countersink bit.

A real countersink bit works better, and is easier.

You need to remove the gelcoat around the hole edges, otherwise the screw itself will chip the gelcoat when you screw it in.

 

[90stingray]

Re: Transducer Mounting-which bit to drill through the hull?

I have always used the wood paddle bits. I use the size i need and run it in the correct direction for the bit. Never had any chipping of the gelcoat. Hope this helps.

 

[Thalasso]

Re: Transducer Mounting-which bit to drill through the hull?

People recommend masking tape, running the drill in reverse, (I’m not sure how that is supposed to works) but I’ve always just used a center drill to get things started and went from there. When done, hit it with a 82 degree countersink to smooth out the edges

When you run the drill in reverse to countersink the hole it doesn't grab the surface because it is running with the countor of the bit