Repairing a fairing

[Nai]

I have a cracked fairing, its quite a big crack, about 3 inches and its taken a bash. The crack is on the bottom of the fairing and not to visible but it annoys the crud out of me that its there. I am guessing as its plastic I might be able to weld it together with a soldering iron or something. Is this possible or does it screw the plastic up? I am sure I read somewhere on this forum about mini blow torches from either lidl or aldi for £5. Would something like that do the job? Or am I better off buying a a glue or something?

[robocog]

Just repaired some cracks and missing bits on the GPZ fairings/panels

Fastest method
lego brick and soldering iron
seems as strong as original

I did pop some cut up lego bricks into some acetone and created a thick "goop" (in a sealed jam jar it took a day or so of adding lego chunks and stirring it in till I had a good consistency)

I used tape to create a backing/mould and poured it in to a section that was completely missing, the tape held well and it formed a skin very quickly, but it didn't want to set or cure very quickly, where just soldering iron and lego method set whitin seconds and was ready to sand/prep

the moulded from goop parts have taken a good few days (even in this heat) to fully set/cure and go fully hard
It doesn't seem to have solidly attached to the original panel and it also showed some signs of shrinkage, but has created a part that can now be soldered / blended in and sanded back down to shape

This is for the GPZ500, where the panels are made from ABS plastic
Lego is also made from ABS plastic

Acetone is a solvent and dissolves ABS plastic very well (bought 5l of the stuff for £9 from a paint supplies shop, local chemists stock it but will only sell weeny little bottles of it at extortionate prices)

ABS goes tacky on contact and will turn to a liquid if exposed to it long enough
The Acetone will completely evaporate in air...eventually

do either method somewhere well ventilated (it stinks and possibly not that great for you if exposed to it for long periods) and bare in mind that the soldering iron tip will require a good cleaning up/sanding and re-tinning if wanting to use it as a soldering iron again

Regards
Rob
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Needs a bigger garage...

[Carvel]

https://ducttape.umwblogs.org/files/2009/03/duck-tape.jpg

How did you manage it, have you had a spill?
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2002 Aprilia RSV1000R, Cbr600Fs, Mk1 B12, Vfr400 NC30...

Matt B: I can deal with crushed nuts to beat Ollie.

[robocog]

I bought mine with broken and missing bits ....not guilty as charged

Regards
Rob
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Needs a bigger garage...

[Teflon-Mike]

https://www.bikechatforums.com/viewtopic.php?t=199042&start=50
Over on Show & Tell, Snowtiger has done a bit of a how to on plastic welding, from pics she took when I showed her on some bits of her bike.
Basically, soldering iron.
Electric NOT gas, you want to melt the plastic NOT burn it.
Scrap plastic of a similar consistency, from anything you have lying around; old mily bottles, fabric conditioner bottles, cracked staka-boxes, washing up bowls.... not tried leggo-bricks... but hey, they're plastic! Havce too see what has escaped the kids toy-box next time!
On something very cosmetic like a fairing, and if you are not painting, then you need to make the repair as invisible as possible and ONLY work from the back, going as deep into the plastic as you dare with teh soldering iron to create a moulten puddle accross the crack, into which you melt the scrap plastic filler, and mix about to get a good consistency of plastic accross the joint, as you work along its length.
IF you are going to re-paint, you can work both sides and not be as critical, filing and sanding the front face after welding then using high-build prime to smooth over, before priming and painting the whole part.
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My Webby'Tef's-tQ, loads of stuff about my bikes, my Land-Rovers, and the stuff I do with them!
Current Bikes:'Honda VF1000F' ;'CB750F2N' ;'CB125TD ( 6 3 of em!)'; 'Montesa Cota 248'. Learner FAQ's:= 'U want to Ride a Motorbike! Where Do U start?'

[Nai]

Thanks Robocog, that's a lot more than I thought I would do to repair a fairing If it works its worth it though aye ty

I would love to gaffa it, I would also love to give you an epic tale of how some bugger cut me up, knocked me off my bike right before i chased him down at the lights slapped his bonnet with my nob and screamed F*ck you motherf**cker! before doing a wheelie and setting of a dozen speed cameras as i burnt up the road.

But i cant.

I park my bike at the edge of a car park with a grassy verge. Came out tonight to find it standing in the wrong position with grass stains up the side. First blood on my bike and I am denied a dramatic story of biker heroism. Bah!

Edit


Thanks Teflon Mike as-well, posted while I was posting.

[Carvel]

Ah what the hell some bastard knocked it over. Is there any cctv or anything kicking around to catch the bastard.

[Teflon-Mike]

[Nai]

Quick update, finally got on to doing this today, the 3 inch crack is now 6-7 inches and had gone off in 2 directions, my fault should have done it sooner but really busy in with life at the moment.

I had real trouble taking the fairing off due to it being stuck like it had been glued to the nose and I didn't want to break anything else. I am aware of the fact I am heavy handed and generally apply more force than is necessary on things.

I soldered back and forth across the crack and 'stitched' it as-well as melting / pooling in some black plastic of a Lynx bottle. I didn't do a particularly good job. Part of the reason I am unhappy with the job is based on how big the crack got. It sort of chipped in a few places so there was a few small holes up the crack. I also don't think I was thorough enough with the stitching / melting of plastic, but hey, was my first go.

I will have another look either tomorrow or Monday.

Thanks again for the help folks!