My car has fiberglass fenders on all four corners. The paint is severely deteriorated and needs to come off.

What is the best way to strip the paint from the fiberglass parts and leave the gelcoat intact? I've been wet sanding with #150 wet/dry sandpaper and I'm getting pretty good results but it is more labor intensive than I like.

Check with your local paint and body supply store, but I believe aircraft stripper will not eat the gelcoat.
Sanding with a D/A sander is usually the best way. I would use 220 grit, myself...

Thanks for that. I'll check with my aircraft supplier.

Do not use a da sander on fiberglass or plastic.

Your doing it the best way you can.

The Aircraft stripper will make the fiberglass kind of gooey and then you run into all types of terrible problems. The da will work if you are sure handed, but more than likely you'll make it wavy. when fooling with Fiberglass I usually try to wet sand with 180 or so unless time is of the essence

You should be fine using a DA sander if you use a 6" pad, keep it flat and keep it moving. Stop when you start to hit gelcoat and wet sand it from there. It really depend how much paint you're taking off. If you're happy with the progress keep going. If it's gonna take you a year to finish a DA would pick up the pace a little.

STOP USING THE 150!!!

Its incredibly painstaking but i wouldnt trust anything other than sandpaper. Use a block, because it will wear evenly, and be very careful. There will be parts of the paint that will come off faster than others, dont burn through the fiberglass.

Also, once you get past the clearcoat, or the very top coat of the paint, switch to 320. It will take longer, but the scratches you make with the 150 will be deep enough, that when you go to take them out, you will go too far. Also, wet sanding is slowing you down. Step up to 320 and go dry. Easier to see what youre doing this way too. Worked well for me this way, but i learned the hard way on a different panel, and went too far.

Fortunately I live in a country where I can hire a robot to do such no-brainer work for about US$6.00 a day. Unfortunately, the robot won't be back until the 15th and I'll be in Korea on that day.

I went internet shopping for "fiberglass safe" strippers. The best i could find was something that is safe for "most" gelcoats. Scary. Also, at $55/gallon plus shipping and hazmat charges to the Philippines, it is not very attractive from the economic standpoint.

I think I will stick to hand sanding. The car is now black. It was previously white. The white paint is still there. I guess I get my robot to get through to the white paint and I will take over personally from there.

Sanding with a machine would certainly save a lot of time but I do not trust myself enough to do it that way. Knowing myself, I would probably just end up making more work for myself.

I'd like to thank everyone who has chipped in their ideas so far. I think I'll be able to post pictures of the end result in about two weeks, robot availability being the only constraint.

Cheers!

I finally got someone to start sanding the black paint off the car yesterday. I bought a stack of 240 grit wet/dry and set him on the car. It took him the whole day to almost finish one rear fender. He is back today and working on a front fender. I figure it will take about 7 working days to get the whole car down to the gelcoat and white basecoat (for the sheet metal parts.)

I hope to be able to post pics soon.

Again, thanks for all the inputs!

Cheers!

Its alot of work, but its being done the right way!