What is easier to work with, ABS plastic or fiberglass?

[dpmotley]

Hey everyone. I'm new here and I apologize if this question has been discussed already.

I have a project on my mind. I want to adapt an Audi A4/A5 S-line side skirts to an Audi A3 8PA (sportback). For some reason I like the A4/A5 blade style side skirts more than the genuine S3 ones. As they are longer then the A3 can accommodate, I'm going to cut a piece off the middle and join two parts together. The question is what to choose: fiberglass or ABS plastic?

I can get the aftermarked side skirts inexpensive off ebay, but most of them is made of fiberglass. The price of ABS plastic made ones is double.

I know that ABS plastic is more flexible than fiberglass. But what of them is easier:

- to cut/saw (I'm going to use a hacksaw)
- to clue
- to putty and prepare for spraying

I don't want this project to be too expensive too. I'd appreciate any advise.

The image below is manipulation but it shows a desired result.

[Delighton]

In fact, ABS is stronger and more durable than fiberglass. It also offers fit and finish that's superior to fiberglass.

[henri12]

Fiberglass will take lots of prep for painting.

[DaleCarter]

Superior to fiberglass? Literally millions of boats and Corvettes would argue against that.... equal, sure.

Personally, I find FG MUCH easier to mold and shape to my needs and repairs are SUPER easy.

[DaleCarter]

I have just learned FG repair and performed extensive repairs to my race car panels. I sanded the repairs with 80 and 150, then I sprayed the panels with SlickSand filler and sanded 150, 220 and 600. I could primer and spray just like any other surface, but I chose to wrap because it's race car and repairs are inevitable :-)

For a car that needs to be REALLY pretty, just prep the bare FG and proceed with filler/sanding as you would with metal. As long as you don't sand through the glass sealer, the paint won't know. Properly prepping/sealing FG before finishing is two decades removed from the voodoo that plagued Vette paint jobs in the past.

Prep prior to sealing and spraying color is not much different from metal or ABS. Straightening the surface is often easier.