I have a weathered windshield and was wondering if I can polish the road rash out of the glass. Can this be done without a large investment in special tools?

You need a miracle. Or a new windshield. I tried one of the glass polishing compounds with the different pads and whatnot and it was a serious waste of time and effort.

You can still get new windshields.

You can polish scratches that if you drag your fingernail over out usually but ones that catch your fingernail, you'll usually polish through the tempered layer (thin hard layer) and will end up distorting the surface so its noticable. Unless you polish the entire surface equally. It is extremely time consuming. If the slight distortion isn't a concern for you and you have the time, you can polish them up nice. Use lots of water to keep glass cool so it won't shatter from local heating, and take your time.

My personal belief is that there's a reason that many professionals wont do it anymore. Too risky, too much time.

Eastwood has a kit with abrasive disks, abrasive compound and polishing pad. Works great but teeeeedious.

There are machines that will do it quicly but expensive and I don't know how well they do on curved stuff.

Good luck.

I bought one of the eastwood polishing kits, and imo, it's an absolute waste of $50

put the same money towards a new windshield

like said , if it catches your fingernail chances are it won't polish

EASY! Only 2 steps!

Step #1: Remove scratched glass
Step #2: Discard and replace with new unscratched glass