Noticed a huge difference in my block sanding after switching to a foam block

I used the same rubber sanding block for five years straight, then tried a 3M soft foam block on a 2018 Civic door last month. The foam block let me flex around the body lines way easier and I cut my sand time by almost 20 minutes. Has anyone else made a similar switch that changed their finish quality that much?

3 comments

3 Comments

kai_burns7313d agoMost Upvoted

Swapped to a closed-cell foam block last year on a rear quarter panel that had a bunch of compound curves and never looked back. @samrodriguez pretty much nailed it in that write-up, the foam just follows the body lines like it was meant for them instead of fighting you the whole way. Flat panels still get the rubber block for me, no question, but anything with a curve or a body line is foam all the way now. The time savings alone on a whole job makes it worth keeping both in the drawer.

fionafoster13d ago

Had a buddy who swore by his old rubber block for years, wouldn't touch anything else. Finally talked him into trying a soft foam block on a tricky fender repair he was fighting with. He called me that night kinda amazed... said it hugged the curve around the wheel well like it was made for it. Said he didn't have to fight the high spots and low spots so much anymore. He still uses the rubber block for flat panels but keeps the foam one in his box for any body line work now.

samrodriguez13d ago

I read a write-up in a car forum once where a guy tested six different sanding blocks on a curved door skin. The foam block left a smoother contour with way less effort compared to the rubber ones. It really seems like having both types in your toolbox just makes sense for different jobs.