How to fix crack in plastic fender

[Boomerang1]

A lot of people think that most plastic body panels and fiberglass panels are the same but they just misinformed. Most fiberglass parts are made by spraying or laying fiberglass cloth or mesh in a mold and then saturating it with a resin that is mixed with a catalyist. I don't know a lot about how plastics are made but some plastic parts are formed by injecting molten plastic into forms or using a vacuum to draw a hot sheet of plastic into a mold. From what I understand SMC is a combination of plastic and fiberglass strands that is formed using heat and pressure. The first time I tried to repair SMC, I thought it was fiberglass because they look similar but the fiberglass patch peeled right off, even though I had used a 16 grit grinding disc. I'm sure there so many new types of plastics used today that I wouldn't have a clue as to what they are called or how they are made.

 

[Cactus]

</font><font color="blue" class="small">( <font color="blue"> I think if you try to use JB Weld, the repair will not hold. </font> )</font>


It has never failed to work for me.

 

[BadDog]

After wrapping the chain harrow around the rear wheel, my fender was cracked in two places (around 12" long) and missing a few chunks here and there. I 'fixed' it three separate times before getting sick of the sight of it... ...$800 well spent in my opinion just to be 100% 'whole' again.

 

[JeffSpencer]

I have "welded" many a broken dirt bike fender. They become brittle during the winter time and snap like a stick when you wreck (usually the front fender). The problem is, you gotta know what kind of plastic to use for filler. I used to cut strips from other broken fenders and use them. Maybe you could get some broken plastic tractor pieces from your dealer and cut some skinny strips out of it. It may be worth a try. It is basically a heat gun. You melt the rod and the crack at the same time while keeping pressure on the "rod."