Sanding tips for fiberglass bike panels

[Paint munky]

I dont do a lot of painting and when i do ive always used new gel coated panels but i now have a few sets of used panels i want to paint and the prep work is taking me days.
I dont have a air DA sander, my comp wont run one. Ive tried a reasonably cheap electric DA from wickes which you guessed it went straight in the bin. And ive tried a palm type triangle shaped sander which is ok but with anything else than a really rough pad takes forever and with most of the panels being curved the contact patch is pretty small.
So ive been wet sanding using 120 grit and even that takes ages to get through the layers of paint so im looking for advice to get this done a bit quicker and to try and retain my finger prints as im quickly wearing them away.
The panels im working on at the minute have a top coat which looks like a rattle can job, under that is a grey primer, then the original red top coat and white primer. How far do i need to go so i dont need to worry about reactions etc? the panels ive done so far ive just about broke through the top coat in places showing the grey primer, is this enough?

 

[steveo3002]

if its rattle can or dodgy looking paint then sand it off at least the orig factory paint

120 sounds a bit savage..but whatever works for you

 

[julieanncharters]

I dont do a lot of painting and when i do ive always used new gel coated panels but i now have a few sets of used panels i want to paint and the prep work is taking me days.
I dont have a air DA sander, my comp wont run one. Ive tried a reasonably cheap electric DA from wickes which you guessed it went straight in the bin. And ive tried a palm type triangle shaped sander which is ok but with anything else than a really rough pad takes forever and with most of the panels being curved the contact patch is pretty small.
So ive been wet sanding using 120 grit and even that takes ages to get through the layers of paint so im looking for advice to get this done a bit quicker and to try and retain my finger prints as im quickly wearing them away.
The panels im working on at the minute have a top coat which looks like a rattle can job, under that is a grey primer, then the original red top coat and white primer. How far do i need to go so i dont need to worry about reactions etc? the panels ive done so far ive just about broke through the top coat in places showing the grey primer, is this enough?

bite the bullet and buy a quality DA like a makita 6in will fly thru it ,no such thing as a cheap DA just die in no time like you said.
do a test and see only way to be sure with reaction.

 

[Paint munky]

Does a quality electric DA exist? Also 6in is a bit big for the work i do, it would make it tricky if not impossible to get in places on the panels. I have a polisher with a 3" pad which is as big as id like to go.

 

[Chipper]

Never really bothered with a DA on bike panels, there's not usually much area that suits them so I use blocks & things.
Are you using sanding blocks? Just using your hand/finger tips will take far longer and not so good for a flat finish. Can buy or make them from odds & ends. As well as proper blocks I've got all sorts of rubber & foam tube, bits of wood, foam that's stiffish but bends a bit, etc etc.

 

[Paint munky]

I did try using blocks but i only have solid ones and i found it easier/quicker with my hands. The idea of rubber or foam sounds a good idea, i'll see what i can find.

 

[GeorgiePorgie]

Might be too course or not applicable for the job intended? I use these on Fiberglass to get a almost level surface.
http://www.toolstation.com/shop/Han...MultiRasp+Planer+140mm+Block/d10/sd150/p87205

Whats a DA?

 

[Paint munky]

Think that maybe a little harsh for taking paint off.

DA=dual action

 

[steveo3002]

yeah id stick with sandpaper of somekind ...without power tools it will be a bit of a slog

are you using decent brand papers? cheapo stuff aint so great

 

[Paint munky]

Yeah im using mirka wet 'n' dry. Im starting to think they used hammerite or something similar to spray them with, even when using 120 grit (which is way rougher than id normally use) i get through a patch probably 6" square and the paper is useless. Using one of those triangle type sanders just clogs it up in no time.

I am starting to lose faith now, this is the 3rd day ive been at it and im getting nowhere. Be cheaper just to go out and buy new panels even at just over a grand a set.

 

[steveo3002]

have you tried wiping it over with gunwash /celly thinners...often takes rubbish straight off and wont touch the original,but be carefull when if you feel it getting sticky

 

[Paint munky]

Yes and it turns to mush but does get sticky rather fast, i thought about soaking a scotchbrite pad in thinners and attacking it with that. Need to pop out and get some more thinners first tho.

 

[steveo3002]

with luck the rubbish paint will wipe off before it effects the factory paint

 

[GeorgiePorgie]

Just thought I'd throw this in as I was browsin for summat.
http://www.ebay.co.uk/itm/Professio...Air_Tools_and_Compressors&hash=item4aac627442

 

[Paint munky]

Just thought I'd throw this in as I was browsin for summat.
http://www.ebay.co.uk/itm/Professio...Air_Tools_and_Compressors&hash=item4aac627442

Im pretty certain that'll be a waste of time, so time ago i brought a cheapo 3" air DA of ebay and my comp wouldnt even run that properly (Comp is a 100L Fiac 2.5HP) it just stopped when you applied for any longer than 10 seconds.

After today ive admitted defeat and arranged to take all 4 sets of bodywork of to be soda blasted.

 

[graffian]

You say fibreglass, do you mean fibreglass or the stock panels?

The soft plastic is OK with paint stripper, I used to strip GSXR fairing middle bits back to bare plastic with it. The hard panels don't like stripper and go soft and bubbly[they are ok when they have been left for a month or so].
You might find some of the modern strippers are ok on the hard plastics, I
guess methylene chloride is a solvent for the type of plastic used for the hard bits. It's not as problem to find a bit of fairing out of site to test the stripper on. Fibre glass isn't a problem to strip with paint strippers, paint shops sell stripper OK for fibreglass.

 

[Paint munky]

No i mean fiberglass, not the cheap stuff tho. These are made by silhouette japan and come in at around £1000 a set unpainted hence why im going to the trouble of repairing/restoring them.

 

[ibrooks]

Sounds like you've got a solution but for future reference......

http://marinestore.co.uk/Dilunett_Gel_2_5_Litre.html

I've used this quite a bit on fibreglass as a paint stripper. just don't get it in any cuts as it stings like billy-oh (yes even more than Nitromors).

Iain

 

[Paint munky]

Thanks, that stuff looks pretty good. I'll order some anyhow and see how it does as the soda blasting is great but for one its costs money and 2nd, i have to rely on others to get it done.