Best way to cut fiberglass....
05-07-2007, 09:28 PM
#1
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Best way to cut fiberglass....
I'm have a few projects I'm in the midst of and have come to the hard part.....cutting out a section of fiberglass, it's on interior peices. Nothing to do with the structural integrity of the boat. Just adding some upgrades.
The question is, What is the best way to cut fiberglass clean and straight? Jigsaw (type of blade?), rotozip? I know you can give the best advice Pat, what do you got?
The question is, What is the best way to cut fiberglass clean and straight? Jigsaw (type of blade?), rotozip? I know you can give the best advice Pat, what do you got?
05-07-2007, 09:53 PM
#2
I cut all of my speakers with (8 of them) with a Roto-Zip type tool. (Mine is a Ryobi, but takes Roto-Zip bits.) I advise using the heavy duty tile cutting bits, and not the light duty plastic cutting bits. Cut swiftly and smooth, as not to go so slow that the bit heats up. As soon as that bit heats up and discolors, its going to break. I never found a few pieces of those bits! You want full wrap around eye protection, and a full face shield if available. If you can keep the shop vac running at the base of your cut while cutting, it will help keep the mess at bay.
05-08-2007, 12:59 AM
#4
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I used a jigsaw with a medium tooth scroll type blade. The secret is to cut using a slow blade speed. Running the blade fast will only get it hot and dull faster. It took me about 6 blades for 4 6x9 holes. Also put a layer of masking tape about 2" around the area to be cut.
05-08-2007, 08:31 AM
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Roto-Zip type tool for sure (I have a DeWalt but takes the same bits). I highly recommend eye AND EAR protection, the suckers are loud and if the area is hollow - even worse, I was deaf for like an hour after I was done with two speaker holes. Same with going too slow - if you go too fast it will heat and snap the bits. You will break at least one - guaranteed! So, buy a couple and get the tile bits as mentioned, not cheap but good. (I know my DeWalt turns about 30k and when you break a bit...) 
The shop vac trick works great too, keep it right under the bit and it will be clean. Also use 2" masking tape to tape off the area and cut through the tape, keeps the cut cleaner.
The shop vac trick works great too, keep it right under the bit and it will be clean. Also use 2" masking tape to tape off the area and cut through the tape, keeps the cut cleaner.
05-08-2007, 09:05 AM
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Is this day over yet? I nned to get home and make a mess!! Luckily the peice I am working on is off the boat. The wife was holding the shop vac last night and that kept the mess way down. I think I need to take a road test to lowes or Home Depot....
05-08-2007, 02:33 PM
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Here’s how I would do it.
First head out to home depot to buy drill bits for the Roto-zip. Stop and pick up a few handles of Captain Morgan, 1 bottle JD, 1 bottle grey goose, and 6 red bulls. (don’t forget ice)
Fill a pitcher full of red bull / vodka, and another full or Capt. / Coke..
Have a couple Captain and cokes.
Measure where you need to cut.
Drink some of the Redbull / Vodka to keep steady and focused
Have some more Captain because you don’t want to lose the buzz.
Remeasure because at this point you have decided to move the speakers to a different location.
Why not have another……
With masking tape, cover everything because you are going to make one hell of a mess.
Cut a hole in the plastic because you realize you needed a way to get out. And you left the drinks out side the boat.
Have another, and another just in case…
At this point……. Put the cover back on the boat and have the wife go to the store because you will be out of cocktails.
Then call a fiberglass specialist and enjoy the evening.
Let me know how it comes out. 
First head out to home depot to buy drill bits for the Roto-zip. Stop and pick up a few handles of Captain Morgan, 1 bottle JD, 1 bottle grey goose, and 6 red bulls. (don’t forget ice)
Fill a pitcher full of red bull / vodka, and another full or Capt. / Coke..
Have a couple Captain and cokes.
Measure where you need to cut.
Drink some of the Redbull / Vodka to keep steady and focused
Have some more Captain because you don’t want to lose the buzz.
Remeasure because at this point you have decided to move the speakers to a different location.
Why not have another……
With masking tape, cover everything because you are going to make one hell of a mess.
Cut a hole in the plastic because you realize you needed a way to get out. And you left the drinks out side the boat.
Have another, and another just in case…
At this point……. Put the cover back on the boat and have the wife go to the store because you will be out of cocktails.
Then call a fiberglass specialist and enjoy the evening.
Let me know how it comes out.
