Basic Bondo question guys...new @ this

[Topless69]

Hey guys I'm new at this body work stuff and have a basic question.
Ok um...I have finished welding 16g panel for my smotth firewall project and am very close to the bondo step. QUESTION- Should I bondo over the bare metal first or prime everything first then bondo?
Heres a quick pic. My cat is inspecting my work..!!

[jilge71]

i would go right over the metal after its ground unless its going to be like this outside for a while...you could put an epoxy like they do after sand blasting but i dont think you need to. i would prime and paint the inside if there is any burn through from welding

[67rsssls]

I'll second that. It sticks best to bare metal.

[oestek]

You may want to rough the bare metal with a sander before filler.. give it some "teeth" to grab. Some guys like to run as rough as 36 grit if doing the whole panel, others 50... 80 seems to do more "polishing" than scuffing.

[Topless69]

I posted this over at TC also and between them and you guys PLUS reading all kinds of archive threads it's a 50/50 toss up..!!! some say ruff bare metal some say etching primer some say epoxy primer. some say a WATERPROOF filler like "allmetal" on first coat of filler.
I don't know what to do..!!

[ErikLS2]

I'm in phoenix and put bondo right over bare metal on my car, which I did with a friend who's a 20 year body man and repairs Ferraris, Rolls, Bentley's, etc. The newest thing is epoxy primer first, then bondo, then another coat of epoxy primer. This is supposed to give best corrosion protection. You're in NY, higher corrosion, probably the new way is best for you but epoxy primer is expensive. On the other hand, most of these cars we build don't see harsh weather and certainly not salt so the original method of bondo over bare metal is find for most.

Just my .02 worth!

[Topless69]

Thanks erik, Thats kinda the answer I needed. Your right my car doesn't even see rain let alone salt and $ is an issue. i am going to have it painted "hopefully" next year provided the funds so I will be having a pro do it. For now I'm painting the eng. conpartment to match the outside. I put alot of work rebuilding the eng, and making it nice on the eyes and didn't want to stick it in a crappy looking eng. conpartment.

[poormans69]

Nobody recommended kitty hair filler? Must have been too easy.

[mikey]

Nobody recommended kitty hair filler? Must have been too easy.
No it's to much trouble to catch and skin the neighbors cat:lmao:.

[Declawed69]

Take a look at this if you haven't seen it.

http://autobodystore.com/filler_&_epoxy.shtml

[LateNight72]

Take a look at this if you haven't seen it.

http://autobodystore.com/filler_&_epoxy.shtml
There are too many flaws for that to be a legitimate test..

[jackfrost]

Southern Polyurethanes has 2 gallons of epoxy for less than $150 (it's 1:1 with activator). for me, it's worth the extra insurance.

[JRouche]

I did the epoxy over bare metal route. SPI is some really nice stuff. JR


Started with a total stripping of the paint and body filler, down to shiny metal. Some hammer and dolly work along with some welding. Epoxy. Then body filler and glazing putty and a LOT of sanding. Then another coat of epoxy to seal the filler and some sand through spots. Then three coats of high build 2K primer. Block sanding forever. And finally today, three coats of epoxy. All SPI products. Good stuff.

Now she will sit in epoxy for maybe a year while I work out some details. Like proper door and fender alignment. Final engine bay work. Stitch up the loose wiring. And focus on the interior.



After the stripping with a D/A and 80 grit paper. A lot of paper LOL

https://static1.pt-content.com/images/pt/2009/01/strippeddrivers-1.jpg

https://static1.pt-content.com/images/pt/2009/05/strippedpass-1.jpg


After the SPI high build primer. I forgot to shoot some pics of the epoxy over bare metal, but its there under the HB primer.

https://static1.pt-content.com/images/pt/2009/01/highbuilddrivers-1.jpg

https://static1.pt-content.com/images/pt/2009/05/highbuildpass-1.jpg

After the dry guide coat

https://static1.pt-content.com/images/pt/2009/01/dryguidecoatdrivers-1.jpg

https://static1.pt-content.com/images/pt/2009/05/dryguidecoat-1.jpg

This is a shot of the block sanding process. The stuff in a buff color has been blocked down. Took three weeks to block sand the guide coat off. Little pressure and LOTS of paper changes...

https://static1.pt-content.com/images/pt/2009/01/blocksanding-1.jpg

And then today. The final coat of epoxy.. This was about five hours after spraying. Im gonna put the car out on the driveway tomorrow to make sure to bake out any solvents. Gonna be HOT here tomorrow...

https://static1.pt-content.com/images/pt/2009/01/epoxydriversfront2-1.jpg

https://static1.pt-content.com/images/pt/2009/05/epoxydriversfront-1.jpg

https://static1.pt-content.com/images/pt/2009/05/epoxydrivers-1.jpg

https://static1.pt-content.com/images/pt/2009/05/epoxypassfront-1.jpg

https://static1.pt-content.com/images/pt/2009/05/epoxypass-1.jpg

[Chevy Eleven]

Looking good!!