Any way to mend smashed plastic?
 

My left side rear plastic (the part that covers the subframe, under the rear seat) is smashed. It was a hit and run (I wasn't on it) and insurance will be replacing it, but I was hoping to get my old stuff usable enough to do track days on. What's the best way to mend this so it becomes somewhat usable?

I'd try taking a heat gun to it to soften it up enough to push out where you want.

There's a fine line between softening, and melting, but if you don't care about how it looks, it might be an option. I haven't tried it, just tossing that out as an idea.

Then what? :boobs:

Hell man, you already have zip-ties in there! Those pass as fasteners in most track day organizations!

What? Are you worried about your ride not blingin' enough? LOL

eta: Did you heat it up already? :D

In the plastic? Nothing has been done to it yet. The crack is vertical behind the front fastener, so it bows out at speed. I fear a premature ejaculation of plastic on the front straight. Or on the I-15 on the way to the track.

You could try plastic welding, but it doesnt really hold up in the long run, maybe some duct tape would work?

plastic weld

buy the stuff...follow instructions

Hardest but most thorough to easiest and flimsiest...

Option 1: Scuff it up and fiberglass it from the inside. Put a final piece on the outside to finish it off.

Option 2: Drill 4 small holes, two in front and 2 behind the crack, rivet a small aluminum plate in place to hold it together.

Option 3: Same as 2 but use zip ties.

Buy a cheap plastic welding kit. You can either buy abs plastic rods or melt down LEGOS (forgot what to use).

I like Option 1 the best...

I'm with the Jew... duct tape.

3M plastic repair and fibreglass mat. The 5885 works well with motorcycle plastics.

http://www.toolrage.com/prodview.asp?sku=3MA-5885

http://www.youtube.com/watch?v=gMr9aJ-j0NQ

There are many ways to skin that cat, several good ones already mentioned.

Problem w/ plastic-welding, there's a fine-line between good penetration/adhesion & over-melting/distorting the plastic. Takes far amount of practice/feel to get a good quality repair - and you gotta buy a tool.

Various adhesives/epoxies can also do a good job - but they're still just gluing the pieces back together. I've used Devcon plastic repair epoxy with good results (~$3, WallyWorld), That 3M stuff PC posted would undoubtedly work great & also work as a sandable filler to prep for repainting - pricey though. Stay away from fiberglass-reinforcing resin - not good for adhering to ABS, and far better products available.

My favorite & IMO by far the best product for crack-repair is acrylic powder/solvent (I forget the chemical name). Cheap, easy to use, quick, no particular skill required - and most importantly STRONG. Like at least as strong as the existing plastic strong, since it doesen't just adhere to the pieces, it chemically fuses to them & the cured powder seems to be a bit stronger than regular ABS (made a test piece, and the plastic broke before the repair did).

The two brands I've used are Plastex (expensive), and http://www.plast-aid.com/ - from what I have read, it's the same stuff as acrylic nail powder/solvent avail @ beauty supply places, but the cost is similar & I figure the stuff specifically for plastic repair might be a different formulation/strength so I went with that.

My bro & I are resurrecting a CBR & just last weekend repaired a tail fairing which looks very similar to the damage you posted. He did a great job with it in an hour or so with zero prior experience. I'll try and remember to post a pic this evening. It will still need a bit of filler/high-build primer to complete the cosmetic repair on the outside - but the strength & ease of the structural repair is unbeatable, IMO.

I've seen the 3M stuff used to rebuild recessed fairing mount points, that were completely ground away in a lowside.

Ditto with tabs & such using the acrylic powder (forms a putty with a few minutes work-able time) - the guy that turned me onto it used it to fill the headlight openings on his wife's SV, making it a 'track fairing'. I don't doubt it's an excellent product, though a bit pricey - I'm not aware of anything 3M produces which isn't on both counts. :)

Right on both counts :lol:

You going to Willow?

I dunno, I had a very easy time learning, the part in the thread below eventually did crack again, but it took 2 years and at least one crash. I aways felt that the welded area felt more brittle though and any decent bump or jolt has the ability to break it. I wish I knew where I have the photos with my CBR fairing fix on them, but here is my old ex500 with the repair I made.

Ok found it: gonna copy paste from another forum to a new thread here.

If you are interested in plastic welding here it is

http://www.twowheelfix.com/showthrea...470#post459470