[cocomonkeynuts]

What's up with Bondo lately not sanding and gumming up paper? Dry 70-80 degree and plenty of hardener, cured for 72 hours. Switch to evercoat? Something else?

 

[cocomonkeynuts]

Humidity?

Nope dry as a bone the last couple weeks. Any folks from the coast would just shrivel up like a sponge here!

It's still soft like the hardener is no good. I would suspect a bad batch other than this is the third can from a different store from a job I did a month ago same thing. Basically I need a new piece of 60 grit for each side of a window to smooth it out. Gonna be here all day at this point

 

[cocomonkeynuts]

What are you using it on mostly?

last month new construction the carpenters in a $2M condo installed the ceiling crown molding but some places 1/4-3/8"gap. so we scribe a line and make it flush with the ceiling. yesterday basically a spot fixing imperfections in windows. everyone locally I talked to told me same thing bondo is basically worthless last couple years. time for a replacement.

 

[cocomonkeynuts]

I used it on a car in 2020 and 2021 and I didn't really have much experience with it, but imo it did take longer than expected to get hard. One thing I found really helpful is thinning it with acetone, it made it easier to work with/knife down, and maybe helped it cure faster, too. In the end I usually just accepted it sanded kinda mediocre and would do my final pass with glazing putty to fill in the sanding scratches. Thought it was just me, but maybe it wasn't. I really like the Bondo red glazing putty, though, it's awesome stuff.

I think for interior use perhaps instead of Bondo you could switch to Durham's Rock Hard Putty. Exterior it does fail, though, and it's very brittle and has almost no flex. Still, water mix to as thick or thin as you want and no fumes, I'd rather use it any day of the week over Bondo indoors. However, I do think it does flash without being primed, unlike say, Elmer's Wood Filler.

another fella I talked to was skim coating some F'd up built ins the 'high end' carpenters installed. said his festool was basically burnishing the bondo and the oil FPE was just slipping off wherever bondo was applied. He was raving over some ICA 3k polyester filler that's supposed to be the best out there but I'm not about to start importing general purpose filler from Italy just to fix some lazy carpenters mess