general automotive painting query. Using filler

[bennjamin]

hullo all....

painting a fairing for my bike.Its fibreglass , painted.
The fairing has very minor scratches , and a few chips along edges etc.

What filler do people suggest on here to use ? Hopefully something on a tube size basis as i dont need much.

thanks ! Ben

[aaronng]

Have you considered K&H paint stuff that they sell at supercheapauto? Good stuff at good price. Good enough that 3M bought them over and let them keep selling their K&H products.

[Sp00ny]

Have you considered K&H paint stuff that they sell at supercheapauto? Good stuff at good price. Good enough that 3M bought them over and let them keep selling their K&H products.

The K&N paint/filler products themselves are quite good as mentioned. However, their spray cans are designed very poorly. You get an uneven spray pattern and clogged nozzles quite easily when comparing them to WhiteKnight, Dulux etc.

If they're only minor scratches, have you considered sanding them down evening out the surface and using a High Filler (aka "Spray Putty") this is just a thick paint based filler which is good for evening out blemished surfaces and takes minimal effort to apply. Using filler for scratches seems a bit of overkill unless they are very deep.

Also with plastic fairing due to the fact that fairing is plastic thus being flexible, if you use filler, over time you will find the filler will crack or peel.

I may be able to dig up some photos when I sprayed my old pocket bike Pearl Blue... I only prepped some minor parts with High Filler as it was still in good condition. Wow, that was a long time ago... I feel old... haha

[aaronng]

The K&N paint/filler products themselves are quite good as mentioned. However, their spray cans are designed very poorly. You get an uneven spray pattern and clogged nozzles quite easily when comparing them to WhiteKnight, Dulux etc.

Yes, the spray can and nozzles are probably brought in from china or somewhere cheap, hence the problems. The products themselves are quite reasonable given their low prices. What I usually do is if I find a spray can with a good nozzle, I pull the nozzle off once the can is finished so that I can use it on other good products with shitty nozzles.

For fiberglass filling, the 2-pack epoxy filler would be better. No spray cans and it can fill even deep cracks. It comes in small containers of 500g too.

[Sp00ny]

Yes, the spray can and nozzles are probably brought in from china or somewhere cheap, hence the problems. The products themselves are quite reasonable given their low prices. What I usually do is if I find a spray can with a good nozzle, I pull the nozzle off once the can is finished so that I can use it on other good products with shitty nozzles.

For fiberglass filling, the 2-pack epoxy filler would be better. No spray cans and it can fill even deep cracks. It comes in small containers of 500g too.

Haha, I do the exact same thing. I've got a nozzle off an old can of Dulux Enamel paint from a long time ago that fits on the K&H's and I just use that. Spray pattern is similar in shape to a gravity gun.

I don't think fairing is Fibreglass though, its usually ABS/Resin Plastic. It depends alot on how deep the scratches the chips are. If they are minor as Bennjamin mentioned, I would suggest a light sand and High Filler.

[bennjamin]

guys the fairing is fibreglass. its a fake/copy/whatever.
It is prepainted tho , so sustains some sort of smooth surface.

I intend to light sand and fill.Repeat ad nausea until happy then get on with the painting and clear coating.

FYI th cracks are very minor (1cm> dia.) chips on edges of fairing, a few stress cracks thru the old primer/paint and two flat fill zones on either side approx. 0.5mm deep to fill.

[Sp00ny]

guys the fairing is fibreglass. its a fake/copy/whatever.
It is prepainted tho , so sustains some sort of smooth surface.

I intend to light sand and fill.Repeat ad nausea until happy then get on with the painting and clear coating.

FYI th cracks are very minor (1cm> dia.) chips on edges of fairing, a few stress cracks thru the old primer/paint and two flat fill zones on either side approx. 0.5mm deep to fill.


In that case, if they are Deeper/Wider than just chips/minor scratches then I would use similar to what aaronng mentioned. A fibreglass filler, not as easy to work with as Filler, but it wont crack/deteriorate like normal body filler. You also have to take into consideration the compatability of Two-Pack Epoxy Filler with an Enamel/Acrylic Paint. If your painting it yourself then I'm assuming you most likely won't be using a Two-Pack paint.

Also, A clear coat should only be necessary if your using a metallic paint. Non-Metallic Gloss enamel paints don't need a clear coat. Thus why (also due to metallics being more difficult to match, spray pattern effects finish more etc.) metallics are much more difficult to repair/blend than Non-Metallics.

[aaronng]

Ben, the kahfil stuff will take a 2-pack paint over it. If I remember correctly, the nitrocellulose filler is not compatible with 2-pack.

[Sp00ny]

Ben, the kahfil stuff will take a 2-pack paint over it. If I remember correctly, the nitrocellulose filler is not compatible with 2-pack.

Will he even be spraying Two-Pack if he's doing it himself? Two-Pack paints aren't too easy to work with or get a good finish out of unless your experienced. Also to get the best finish and durability it's best to bake or at least use Heat to accelerate the drying process.

You need to know how to use Reducers/Thinners etc. It's not difficult, but if its just bike fairing I would be using Air Dried Enamel. If it runs or you make a mistake its easier to Sand and blend.

If your getting it done professionally then make sure as aaronng mentioned to use something compatable with two-pack paint, as any good panel beater will use Two-Pack.