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General Category => Maintenance => Topic started by: ribbert on April 22, 2014, 10:18:58 AM

Title: One vs the Other
Post by: ribbert on April 22, 2014, 10:18:58 AM
I'm no expert on this but has anyone actually had first hand experience with fibreglass not taking to ABS plastic or is it just one of those ideas that circulates.

I have put a lot of time into repairing a spare set of body work using fibreglass based on this:

(https://farm6.staticflickr.com/5118/13965023791_c815844bc0.jpg)

These tabs had broken into pieces. I made new ones from fibre glass and under lapped the guard by about 3/4". Given the well documented stress at this point, this repair has lasted about 40,000k's which made me wonder.

Noel
Title: Re: One vs the Other
Post by: movenon on April 22, 2014, 10:51:00 AM
I have used fiberglass a few times on ABS and did run some informal tests.  ABS parts would stick and or add some rigidity but the stuff will not bond or melt into the ABS.  I have had better luck using it as a backing for strength as in gluing a fender up with ABS cement or glue and layering up some fiberglass on the back side for stiffness.  Like most I have used glues, heat, plastic rated epoxy's, fiberglass and plastic welding.  Some areas on the stock front fender are under a lot of stress. Those tabs and the attachment points at the forks.

You are doing good by reinforcing those tabs.. IMO that fender looks good but is of poor design.  I wounder why in the heck Yamaha didn't change it in the 10 years of production.  Seems they could have improved the fender and cross brace easily.

When I get around to it I will add a additional fork brace, mostly to help protect the fender.  We are fighting something else, 20-30 year old ABS. On mine I also opened up the tab hole slightly (after repairing it) in hopes of not having it actually touch or bind against the bolt threads.  Probably a waste of time but it is all I can think of to help the problem.

I like your front brake line.....  :good2:
Title: Re: One vs the Other
Post by: Arnie on April 22, 2014, 07:31:08 PM
I've repaired or reinforced ABS with fiberglass a number of times and not had any problems. 
I did rough up the ABS and the patches were not in high stress areas.  Worked for me.
Title: Re: One vs the Other
Post by: keand3 on April 25, 2014, 09:32:49 AM
I found my oem top fairing beeing repaired with fiberglass when starting my mods on the bike 2 years ago, long story made short, its a reason for why i bought a new top fairing out of fiberglass.

Although the old one would probably hold of a while longer it won't last. As soon as i started gently to remove some of the repair it just cracked and big chunks just fell off. Leaving the old abs plastic area exposed.

I hope that you have more lucke then me  :good2:
Title: Re: One vs the Other
Post by: ribbert on April 25, 2014, 10:34:57 AM
Quote from: keand3 on April 25, 2014, 09:32:49 AM
I found my oem top fairing beeing repaired with fiberglass when starting my mods on the bike 2 years ago, long story made short, its a reason for why i bought a new top fairing out of fiberglass.

Although the old one would probably hold of a while longer it won't last. As soon as i started gently to remove some of the repair it just cracked and big chunks just fell off. Leaving the old abs plastic area exposed.

I hope that you have more lucke then me  :good2:

I suspect, but don't know for sure, that the success or otherwise of repairing ABS with fibreglass has a lot to do with preparing the plastic surface.

Noel
Title: Re: One vs the Other
Post by: keand3 on April 25, 2014, 02:50:05 PM
Quote from: ribbert on April 25, 2014, 10:34:57 AM

I suspect, but don't know for sure, that the success or otherwise of repairing ABS with fibreglass has a lot to do with preparing the plastic surface.

Noel

:good2: