Should I prep fiberglass by sanding?

Arrowhead

Arrowhead

Oldtimer
Doing the underside of a fiberglass cobra body, it's unfinished fiberglass matt. Should I scuff with one of those nylon cup brushes like used on a truck bed or is there any other method?
 
Yes, three choices.
With a DA 80 or 180.
By hand--180.

Nothing serious, just a quick job.
 
Thanks, I was actually able to pickup one of those cup brushes at my supplier before I read your response. Maybe I'll give it a try anyway.
 
Arrowhead;34036 said:
Thanks, I was actually able to pickup one of those cup brushes at my supplier before I read your response. Maybe I'll give it a try anyway.
Click to expand...

Why ask?
 
I knew about the cup brush from reading the forum before and assumed it would be something I'd have to order online, but I would like to do the undercoating this weekend so there would be no time to get one. I posted the question about sanding the fiberglass this morning (didn't see it addressed specifically on the forum anywhere) but had to run over to my supplier during my lunch break anyway and they just happen to have the cup brush. So at the time, it was a legitimate question.
 
I misread the question and was answering for the outside of the body, really most people do not do more the a scuff pad under neath the body, if that much.
Because it is rough to begin with, usually.

If it is smooth, I would scuff with something but if hairy and rough, I'd clean and the epoxy will stick great.
 
I would scuff it with gray scotchbrite, solvent clean it with wax and grease remover and shoot 3 coats of epoxy.
 
Here we do a very quick buzz with 180 DA, then red Scotchbrite. The DA is to keep the scuff pad from getting torn up and allow it to scuff down into the contours.
 
Bedliner down! Never sprayed it before (other than spray can stuff) so it was good practice to shoot it where it really won't be seen. I got the hang of it pretty quick though. Masking was a PIA.


IMG_20140205_142210_598.jpg


IMG_20140205_150751_588.jpg


IMG_20140205_150812_607.jpg
 
That's a big step forward in helping to keep the glass stable long term!
 
You must log in or register to reply here.
Back
Top