Spot Putty Help

[truckster]

I've treated the rust spots on the front of my hood with a rust treatment. I've tried filling the low spots with spot putty (3M Bondo 801) and my first attempt was futile - it hardened too fast (3M's instructions are not very clear on ratio). I tried again with half as much hardener - the Bondo was barely pink. It still didn't seem to stick in the low spots. I tried it without hardener and although it seemed to dry it made a mess when I tried to sand it. There are a couple of possible reasons I've thought of - it's almost 100 degrees, and I'm working outside, and the tube I have is a couple of years old. I used it on my firewall when I first bought it, and it seemed to work fine.

So what spot putty should I be using? What's the correct mix ratio? Should I spray the primer first, and then putty? Any help is appreciated.

Thanks!

The driver's side of the hood was covered with a skim coat of spot putty before I sanded it:

[projectking]

Throw that out and get a finishing glaze

https://www.google.com/search?client...iw=414&bih=697

[projectking]

You will also have better luck cross sanding with a longboard or durablock

[Kim57]

I would put epoxy primer on it first and then do the filler.
Works better for me that way.
But I'm no body man.
Kim

[truckster]

Originally Posted by projectking

Throw that out and get a finishing glaze

https://www.google.com/search?client...iw=414&bih=697

Thanks. I've got some on order.

Originally Posted by projectking

You will also have better luck cross sanding with a longboard or durablock

Also have a Durablock set on order.

Originally Posted by Kim57

I would put epoxy primer on it first and then do the filler.
Works better for me that way.
But I'm no body man.
Kim

That's what I've decided to do. I'm not quite ready for the hood yet, but my next project is the wiring harness. I wanted to paint the firewall before installing the wiring harness, and I wanted to have another panel ready just so I don't waste any paint. My plan is to shoot the firewall with primer today, and any extra will go on the hood. Then I'll have a pretty good idea how much paint to mix up for the firewall.

Thank you all!

[projectking]

I second the epoxy primer, 2 coats and apply filler based on the epoxy tech sheets recommended time. Didn’t want to suggest too much and help spend your money!!!

[mongocanfly]

all of this is bad...( it's almost 100 degrees, and I'm working outside, and the tube I have is a couple of years old)
.... epoxy will help fill most of the pitting...i used evercoat metalglaze...very good stuff...not sure what you ordered..3M ?.....durablocks are good but 1/4" strips of lexan with the corners slightly rounded is better...

[nsb29]

My concern is in your original post you said you were using some kind of rust converter this can cause you a problem It doesn’t always play well with epoxy primer‘s you should never put any type of body filler or glaze over bear metal I would suggest you sand it all down to bare metal and get rid of as much or all of the rust converter as possible SPRI is a good affordable epoxy primer