I read on a forum months ago someone had repaired their cracked fenders by using "plastic welding" and the fenders are good as new. Does anyone know if there's a kit you can buy to weld the plastic back together?

 

JB Weld - you can get it at Walmart

Apply it in the cracked area and build up some on the inside where you can't see it. It will be black... Once hardened you can sand some down if you want.

 

I worked at a lab and one of the scientists would use acetone to weld plexiglass together, dont know if it would work the same on reg plastic. i also used superglue to fix the plastic visor on my helmet, but that may not be flexible enough for body plastic. i'd try the acetone, nothing to lose, you could always use a detergent bottle to cut out a plastic "patch" and use a plastic glue from a hardware store or even silicone.
good luck!

 

they sell a plastic welder at rockymountain and/or dennis kirk .

 

http://www.harborfreighttools.com has a plastic welding kit, my brother bought one to repair the plastics on his 86' honda trx350 4x4 ; the fenders were is bad shape busted up real bad ! You need to use the abs plastic welding rod's for atv plastic's , the welder my brother has take both 110 electric and compressed air ; but they also have one that only require's ac (more money on this one) ! The one my brother has was on sale in April for $29.99 (welder only) Lot No. 41592 50 piece plastic welding rods $5.99 Lot No. 41602 this sale ended April 9, 2007 , but they have new sales about 2 times a month ; just go to their main site and sign up for their free monthly sale flyers ! My brother didn't have any prior welding experience , but he did a pretty good job on his honda for a first timer ; not the best looking job i've seen but at least it's all together again and those fender's were in pieces ! williebee

 

There's a product called Plasti-Weld, it is basically colored sticks that fit in a hot glue gun, you use the tip to melt the plastic,and add the stick to bond it, the colors blend pretty good,you can make heavier repairs from the back,and do a single pass on top,and then shave it down with a razor blade to smooth it out. I got some off ebay a long time ago,but if you do a search on the web,you should be able to find a vendor. I've used them on fenders, and on the bodywork of my son's snowmobile for some belly pan cracks, works pretty good.