Cutting plastic fenders: How?
08-31-16, 06:38 PM
#1
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Thread Starter
Cutting plastic fenders: How?
I'm determined to fit a rear plastic fender to an '85 Fuji. But I can't figure out how to narrow the fender where it attaches to the frame so it fits the old bike. Will a Sawsall work on this fairly thick plastic? If so, what type of blade? I'd hate crack the fender. Thanks.
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08-31-16, 06:42 PM
#2
Senior Member
When trying to cut a small radius, you are better using a coping saw. A fine tooth blade (32 teeth per inch), will make a smooth cut that requires little touch-up.
08-31-16, 06:52 PM
#3
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I just use shears, heavy-duty scissors. You may have to strengthen that area of the fender, though. It will be weaker there after cutting and stresses concentrate there, as elastic waves travel along the fender and bounce off the suspension point. I glue another layer to the fender for strengthening, a piece of a broken fender or a strip out of alu sheet.
08-31-16, 06:57 PM
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In addition to the above, you can use a dremel cutting wheel on lower speed, will probably need to smooth the cut after.
08-31-16, 07:31 PM
#5
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All good doable options. Thanks.
08-31-16, 07:43 PM
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I have used a Dremel tool but found a cutting wheel to be difficult to use for radii. I ended up having good results with a cylindrical burr: https://www.dremel.com/en-us/Accesso....aspx?pid=9901 I cleaned up the edges with a medium round file. Keep the radius as large as possible, stress concentrates at small or sharp corners.
