best way to drill through fiberglass?

[Running_on_Empty]

I want to put a key switch ignition in my 76 sanger....what is the best way to make about a 9/16 hole?

[vee-driven]

I'd say oh i don't know,..........maybe a 9/16 drill bit.

[YeLLowBoaT]

Tape the area to be drilled both front and back... mark where you want your hole, take your time and don't force it.

[Running_on_Empty]

well I've just have never done this before and didn't want to crack the fiberglass.....i figured it was smarter to ask now, than to ask how to fix a cracked dash

[GofastRacer]

A drill bit will FK everything up tape or not, use a hole saw makes a clean cut!...

[sanger ss396]

the best way is to do it in steps start out with a pilot hole in the area of 3/16th then use a hole saw but make sure u go very slow untill u get into the wood then u can add a little preasure. also a trick i have seen is clamp a 1 by 4 on the outside then do the drilling. good luck

[Beer-30]

I have also heard it is good to run the hole-saw backwards to start the hole and then run it forward once the initial line is formed. Supposedly this works with upholstery and 'glass. I personally haven't tried it yet.

[lilrick]

I want to put a key switch ignition in my 76 sanger....what is the best way to make about a 9/16 hole?
Great question, and look at all of the Different and approprite ways to accomplish that task! I love this forum! :D

[GofastRacer]

the best way is to do it in steps start out with a pilot hole in the area of 3/16th then use a hole saw but make sure u go very slow untill u get into the wood then u can add a little preasure. also a trick i have seen is clamp a 1 by 4 on the outside then do the drilling. good luck
A hole saw has a pilot drill bit, just tape it and bore it done deal it's a no brainer!..:D

[GofastRacer]

Hmmm, I don't think a few thousand's will matter too much for an ignition switch!...:D

[BADBLOWN572]

I never use tape. I find that it gets in the way and is pointless. An agressive hole saw will tear apart the tape anyways. What I do is to find out where you want the hole to go. Pilot drill the hole with a 1/4" drill bit. Once you get through, take a hole saw, spin it backwards on high gear. A tip is to find a mandril (?sp) that has the ability to change out the pilot bit. I always remove it and throw in a standard drill bit. The extra 1" worth of length makes a big difference. :) Once you get going in reverse, wait until you get completely through the gel coat and are into the fiberglass. At that point in time, you can start spinning it forward. Apply LIGHT pressure at a high rate of speed. Drill through the hole. If you put too much pressure, you can blow the back of the glass off. :(
Good luck. :)

[GofastRacer]

I never use tape. I find that it gets in the way and is pointless. An agressive hole saw will tear apart the tape anyways.
Of course it will cut the tape duhh, the idea is not to chip the gel and is not pointless, why make a no brainer thing so damn complicated!...:rolleyes:

[Racey]

I'd say oh i don't know,..........maybe a 9/16 drill bit.
Hey, you stole the words right out of my mouth. :D
use pilot holes as well, step your way up to the final 9/16 with a couple intermediate sizes. You can use some masking tape on the gel to help with chipping

[stickmann]

Use a drill press and run the proper sized hole saw through a 3/4" chuck of plywood. Clamp this over the place where you drilled your 1/4" pilot hole. Use the hole saw with a 1/4" pilot drill blank to holesaw through the fiberglass and plywood backing in the dash. You will not chip out the gelcoat and you will not blow out the backside, if you are careful. It tends to make a hole which is square to the dash and most importantly....round. Pretty and accurate; that's how patternmakers do it.

[TRG]

You should always let the tool do the job (Whatever tool is used), however, too much pressure will cause problems (chipping cracking)!
plain and simple!
Hole saw, drill bit,....lol "DREMMEL"!
I like tape, paint/gel jobs are not cheap, and use alot of it!!

[YeLLowBoaT]

You should always let the tool do the job (Whatever tool is used), however, too much pressure will cause problems (chipping cracking)!
plain and simple!
Hole saw, drill bit,....lol "DREMMEL"!
I like tape, paint/gel jobs are not cheap, and use alot of it!!
actaully dremil would wokr pretty dam good with thier circle cutting attachment... just take about 10 passes. I use my router and a circle cuting jig when ever I have to make a bunch of holes in stuff.

[BADBLOWN572]

Of course it will cut the tape duhh, the idea is not to chip the gel and is not pointless, why make a no brainer thing so damn complicated!...:rolleyes:
Well, he asked how to do it and I responded. No offense, but after drilling probably 10,000+ holes in boats, I would think that I might have a little bit of knowledge & experience others don't have. :rolleyes: No matter how much tape you use, if you are using an agressive hole saw & don't spin the holesaw in reverse, you stand a good chance of chipping the gel coat.
To me tape gets in the way if you are drilling holes. I lay out a dash on tape, drill my pilot holes, then pull the tape off of the dash prior to drilling. As long as you spin the hole saw backwards before you actually begin cutting, you won't have a problem. You can see what is going on with the gel while you are doing the task. I do not recall the last repair I have had to have done on a boat that was the result of drilling with a hole saw.
The only time that I use tape is if I am cutting something with a sawzall, jig saw, circular saw, etc... Anytime something is going to be sliding across a finished surface. Then, not only do you tape the area you are going to be cutting, you also tape the feet on the saw. That way you are double protected. Definitely use some sort of painters tape or heavy duty tape. The $.99 tape from harbor freight probably won't work. :rolleyes:

[GofastRacer]

Well, he asked how to do it and I responded. No offense, but after drilling probably 10,000+ holes in boats, I would think that I might have a little bit of knowledge & experience others don't have. :rolleyes: No matter how much tape you use, if you are using an agressive hole saw & don't spin the holesaw in reverse, you stand a good chance of chipping the gel coat.
To me tape gets in the way if you are drilling holes. I lay out a dash on tape, drill my pilot holes, then pull the tape off of the dash prior to drilling. As long as you spin the hole saw backwards before you actually begin cutting, you won't have a problem. You can see what is going on with the gel while you are doing the task. I do not recall the last repair I have had to have done on a boat that was the result of drilling with a hole saw.
The only time that I use tape is if I am cutting something with a sawzall, jig saw, circular saw, etc... Anytime something is going to be sliding across a finished surface. Then, not only do you tape the area you are going to be cutting, you also tape the feet on the saw. That way you are double protected. Definitely use some sort of painters tape or heavy duty tape. The $.99 tape from harbor freight probably won't work. :rolleyes:
Hey, whatever works!.....

[superdave013]

That sanger has to already have plenty of holes drilled in it.
Don't drill anymore in the dash is my $0.000001.
If you must have a key switch can't you just swap put the push button that is already there? If not make a little bracket and catch a bolt on the rail kit, some place on the engine or maybe one of the many bolts by the seat / v drive.
But for the sake of the next guy, please don't drill any more holes in the ol girl!
:)

[thatguy]

Damn, He's probably scared to death now.
I just did my first hole, 1 1/4" for a bilge pump outlet.
Was scared because it is the nicest boat I have ever owned.
Used a hole saw, drilled pilot hole the same size as the hole saw pilot bit.
Taped it, but I agree the tape did nothing.
Spun revers and LIGHTLY went through gel and glass.
Spun forward and went Most of the way through.
Then finished from the inside.
Worked perfect.
Tommy

[Sanitariumflat]

If you use a torch, it will not chip the gel coat. You'll need a new boat, but the gel coat won't be chipped!:D

[Sangster]

Be sure you have all the Tools needed before you start this procedure...Also, have plenty of manpower/ Beer at the ready...And "ALWAYS WEAR PROTECTION"....:D :D :D Please post before & after pics..I dig this kind of stuff...

[sangervdrive]

That sanger has to already have plenty of holes drilled in it.
Don't drill anymore in the dash is my $0.000001.
If you must have a key switch can't you just swap put the push button that is already there? If not make a little bracket and catch a bolt on the rail kit, some place on the engine or maybe one of the many bolts by the seat / v drive.
But for the sake of the next guy, please don't drill any more holes in the ol girl!
:)
Thats exactly what I was thinking I have my starter button and switch mounted on a peice of angle on the stringer right in front of the seat. Don't hack up the hull man.

[old rigger]

While I agree with badblown572 about pre-drilling with a 1/4 inch bit, I've never heard of using the hole saw backwards. If that's his way of doing it I think that's great, but I've never had a problem chipping the gelcoat using the hole saw the intended way. I do on the other hand run a drill bit backwards in the gel for a second before drilling a hole. That'll eliminate any chipping.
The only thing I do differently is once I pre-drill, I go to the back side of the dash and drill into the 1/4 hole with the hole saw (no matter what I'm drilling, switch, tach, small gauge...) until I'm 1/4 of an inch into the wood, then I move back to the front of the dash and finish the hole. This way I don't get any tearout of the plywood as the hole saw goes through the dash (if the backside dash isn't completely glassover with cloth...like it shoud be) and I get a nice looking hole from the back of the dash. After all, this is where I spend a lot of time doing the wiring, I want to enjoy what I'm looking at. ;)

[VDRIVERACING]

The only thing I do differently is once I pre-drill, I go to the back side of the dash and drill into the 1/4 hole with the hole saw (no matter what I'm drilling, switch, tach, small gauge...) until I'm 1/4 of an inch into the wood, then I move back to the front of the dash and finish the hole. This way I don't get any tearout of the plywood as the hole saw goes through the dash (if the backside dash isn't completely glassover with cloth...like it shoud be) and I get a nice looking hole from the back of the dash. After all, this is where I spend a lot of time doing the wiring, I want to enjoy what I'm looking at. ;)
That's a nice tip! I was thinking just be reeeel ginger as you near the back, but this is clearly a pro tip.
For me, the most difficult part is drilling the hole square to the dash surface. Stickmann's idea of clamping a bench-drilled plywood piece as a guide is another slick move.

[River Rat 005]

I was told to use a hole saw from both sides. Makes for a clean cut and it's easier to get the piece out of the saw.

[CoolCruzinCobra]

One more method
For 9/16 size drill a pilot hole,than counter sink a bit larger than 9/16.
than drill 9/16. The counter sink will help from chipping the gel.
I also like to use a dull drill .A new sharp drill might grab and chip the gel.
if using a new drill dull it with sand paper.And like said before let the tool do the job.