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Discussion Starter · #1 ·
Hey there

So I'm in the middle of some large (LARGE) repairs on my bike.
Fairing is where I'm at the moment.
Plastic welding is going along excellently, with my cheapo variable temperature (technically current..) soldering iron made with a light dimmer and a cheap 80W iron. However when it comes to finish I have a couple questions.

I know I need a perfectly smooth surface to paint (I do intend to paint it myself) but doing this with ABS plastic isn't the easiest, is there some kind of filler or something that I can put over the weld (which I'd sand into a slight indent so the stuff has somewhere to go into obviously) and then sand down to perfect smoothness? Is that what primer does?

Cheers

EDIT: I do have an air compressor and a 1.4mm Nozzle Suction Spray gun if that opens up any opportunities.
 

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after you weld your plastic you want to then hit it with some bodyfiller of some sort, probably something like quick putty would be fine.

then sand it down so it's as smooth as you can get it using various paper grades then you want to hit it with some spray putty, allow to dry sand and repeat process until you have a nice even surface to apply your colour.

depending on how fussy you are you can sand with wet n dry between colour coats.

remember, the trick to a good paint job is good preperation.

you'll be amazed at how much an edge will show up when you apply colour.
 

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Discussion Starter · #3 ·
Brilliant! Cheers for the reply
Can I get this putty stuff from somewhere like Repco? Is it actually called "quick putty" and "spray putty"?

Acrylic paint will adhere to it right? (no way am I going near 2pak)
 

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yeah dude, you'll get it from any auto shop. quick putty can sometimes be called knife putty but they're the same thing.

it'll be a relatively small can and if you read the instructions it'll say for use on small repairs. apply it with a plastic putty applier which is just a plastic credit card looking thing. apply and sand then repeat if needs be.

spray putty is called spray putty, it's like a thick under coat and acrylic will be sweet as a nut.

repeat each step until smooth before moving to the next step, nothing worse than thinking " yeah that'll do " only to start to apply colour and see you've got edges everywhere.
 

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Been playing with the idea of stripping my fairings right down for a repair and re-spray but i probably dont have the time.

Either way give this thing a read, absolute best guide I've come across and proves you can get a fairly pro finish with rattle cans.
enjoy:
http://www.fireblades.org/forums/how-articles/67590-diy-paint-jobs-spray-cans.html
 

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Clevermetal:

If you are not too concerned with having a perfect finish on your fairings, then go with your plan, but there are bodyfillers for every type of surface out there and there are alot of different surfaces. The fillers for anything plastic come in a huge variety and are usually broken down into 3 forms, rigid, semi-rigid and flexible. These are specifically designed for their respective applications. Some are for PPe, some are for ABS etc. They are made to be compatible with the particular plastic it is used on and will generally be as strong as the original or usually much stronger. The ABS filler used on an MC22 fairing is usually quite expensive but is a vastly superior product to use with these fairings. It will bond and hold FAR better than any other general purpose fillers. It will not lift, peel or crack with time. Auto body fillers and putty are designed for application onto a rigid steel surface, not a flexible one. ABS fillers are designed to flex. Motorcycle fairings are constantly bending and flexing as the bike is ridden, with temperature changes and high winds hitting them. Use the proper filler the first time as the paint job is relying on them for a base to grab on to. Also, if the fairing was cracked, apply the filler to the backside of the crack and don't be afraid to build it up for added strength. This product will sand easily and finish perfectly. When asking for this product, say exactly what it is to be used on. The extra cost of the proper filler will far outweigh the headaches of a cheap filler cracking or lifting, either just after the new paint goes on, or even a few years down the road.
 

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Discussion Starter · #7 ·
Cheers for the link Arduro

@ Psidey:
I get the need to be flexible, but I definitely don't want it to be stronger than the ABS, because that's the whole reason I want it, so it'll be easier to work than with ABS.
I'm just finding getting a perfectly smooth finish with my ABS weld's difficult, so I thought I could sand them into a slight indent and fill them with some kind of filler/putty etc.

Do you still think I should go ABS specific putty? If so, do you know any names/brands of stuff I should buy?
 

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+1 to psidy
the putty/bog u want should be at least 5 times the price of the normaly general purpose one, should at the least be design for use on bumper bars,
ull also need a spray putty, before the paint

http://www.zionmoto.com.au/DIYrespray.html
 

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clevermetal said:
Hey there

So I'm in the middle of some large (LARGE) repairs on my bike.
Fairing is where I'm at the moment.
Plastic welding is going along excellently, with my cheapo variable temperature (technically current..) soldering iron made with a light dimmer and a cheap 80W iron. However when it comes to finish I have a couple questions.

I know I need a perfectly smooth surface to paint (I do intend to paint it myself) but doing this with ABS plastic isn't the easiest, is there some kind of filler or something that I can put over the weld (which I'd sand into a slight indent so the stuff has somewhere to go into obviously) and then sand down to perfect smoothness? Is that what primer does?

Cheers

EDIT: I do have an air compressor and a 1.4mm Nozzle Suction Spray gun if that opens up any opportunities.
I'd be spraying it with plastic primer first, before you even put in any filler,the plastic primer will bond to the plastic first and then the filler will bond to the plastic primer. id also use 2 pack primer and paint ,it has more flex in it than other paints.
 

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I'm starting to try out plastic welding with a butane soldering iron with a knife tip, just wondering how strong is yours after repairs and what do you use? ABS rods or just old fairings?
 
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