Cutting up boat on tuesday

Seastoke

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Well not quite i am widening the stern door and patio door so we can gain access for electric wheel chair would any one be interested in progress and photos ,roy:)
 

Seastoke

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Whats the best way to cut through gelcoat i am going to use 4.5 inch grinder with cutting discs any better ideas pls ,roy
 
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alt

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jis saw with metal cutting blades, you might mask the area with masking tale & mark your cutting lines on the tape, this will also stop any break-out of the gel

Yes, I highly recommend masking off your area with masking tape for the reasons above. I've seen people take to it straight with their cutting device only to have bits of gelcoat flying off.

And yes with the pics please, will be very interesting reading/viewing.
 

jimmy_the_builder

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jis saw with metal cutting blades, you might mask the area with masking tale & mark your cutting lines on the tape, this will also stop any break-out of the gel

Jigsaw with a reverse cut blade on it should give a nice clean cut. Oscillating multitool does the trick as well but maybe not so good for a long straight cut. I very definitely would not use an angle grinder. Wear a mask.
 

Nick_H

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Why not an angle grinder? I've never had to try and keep a really neat line with one, but i've certainly used one to cut GRP and it works a treat, and there's no risk of chipping the gel coat. I think a normal jigaw blade risks chipping it even with masking tape, in fact i'm not sure the masking tape will make much difference. I agree a reverse cut blade will be better, but then it's harder to keep a straight line because the handset is pushing away from the GRP.
 

jimmy_the_builder

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Why not an angle grinder? I've never had to try and keep a really neat line with one, but i've certainly used one to cut GRP and it works a treat, and there's no risk of chipping the gel coat. I think a normal jigaw blade risks chipping it even with masking tape, in fact i'm not sure the masking tape will make much difference. I agree a reverse cut blade will be better, but then it's harder to keep a straight line because the handset is pushing away from the GRP.

Too fast, too burny, too much debris flying around, not enough control. I don't agree with you about the reverse cut jigsaw, you just lean on the tool and let the tool do the work, don't try and force the cut.
 

Nick_H

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Too fast, too burny, too much debris flying around, not enough control. I don't agree with you about the reverse cut jigsaw, you just lean on the tool and let the tool do the work, don't try and force the cut.

Yes, I should have written "I would exepct that it's harder ...." because i've never actually used a reverse cut blade, but it must try and lift the handset? Less so with a fine tooth blade I suppose. I still think an angle grinder would do the job though.
 

jimmy_the_builder

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Yes, I should have written "I would exepct that it's harder ...." because i've never actually used a reverse cut blade, but it must try and lift the handset? Less so with a fine tooth blade I suppose. I still think an angle grinder would do the job though.

Reverse cut blade is commonly used for clean cutting laminates, where a conventional blade would chip the material.
 

aquapower

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When a boat is being built all trimming is done with a diamond cutter, this is the only thing to give a clean cut, most things can be done with a 4 1/2 in grinder and a steady hand, it pays to have someone else holding the vacuum cleaner close to the cutter. A jigsaw blade will burn out very quickly and will chip the edges, a multi cutter with correct blade is ok for small cuts but will be very slow on anything too thick.
 

sailorman

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When a boat is being built all trimming is done with a diamond cutter, this is the only thing to give a clean cut, most things can be done with a 4 1/2 in grinder and a steady hand, it pays to have someone else holding the vacuum cleaner close to the cutter. A jigsaw blade will burn out very quickly and will chip the edges, a multi cutter with correct blade is ok for small cuts but will be very slow on anything too thick.

a metal cutting blade WILL not
downward cutting blades are not for the inexperienced as they tend to jump
 
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