Body fillers/putty

[Falcon_LS]

I don't really know much about body work and paint, and I am a bit confused about body fillers. I was just wondering if someone in the know can 'educate' me a bit on what all the different colors and materials are.

My Mercury is going in for a paint job in the not too distant future, and I had a highly reputable shop take a look at the body work. One of thing things they said was that red hardener was used on both front and rear bumpers, which is difficult to remove, so the bumper covers have to be replaced. I don't mind replacing them, because the one at the back has a small tear and the one up front doesn't align right with the rest of the body work. But one of things I was told was you never use red hardener on plastics because it causes the paint to flake off with a minor hit (I can literally peel the paint off in chunks off my front bumper). The other thing the guy told me is that red hardener is used to speed up the paint process, and that they use fiber body filler instead. I think he was referring to it as poly putty or something along the lines.

Also, when would one use white body filler and what is its purpose? Thanks!

 

[eljefino]

Whenever doing a bumper cover with paint or "bondo" you want flexibility. Paint can be made flexible with an additive but IDK about bondo.

The bondo body filler I'm familiar with, which they may not have in Kuwait, is a fiberglass resin where you mix light grey goo with red hardener and you get a light pink final product when it sets up.

Regrettably the replacement parts chain often only has bumper covers in a base color and they require painting, with proper flex agents. Since you're painting the whole car you'll be in a good spot with the pigments matching, just make sure they make it flexible.

 

[SOHCman]

Thats interesting, I used some bondo last year and it was a grey putty you mixed with a BLUE hardener, and it dried sky blueish.

 

[Falcon_LS]

Originally Posted By: eljefino
Whenever doing a bumper cover with paint or "bondo" you want flexibility. Paint can be made flexible with an additive but IDK about bondo.

The bondo body filler I'm familiar with, which they may not have in Kuwait, is a fiberglass resin where you mix light grey goo with red hardener and you get a light pink final product when it sets up.

Regrettably the replacement parts chain often only has bumper covers in a base color and they require painting, with proper flex agents. Since you're painting the whole car you'll be in a good spot with the pigments matching, just make sure they make it flexible.


Thanks for the info!

The fiber putty I mentioned earlier is the fiberglass resin you mentioned, although it looks more of a brownish beige color when mixed here. Not sure what they mix though.

Originally Posted By: SOHCman
Thats interesting, I used some bondo last year and it was a grey putty you mixed with a BLUE hardener, and it dried sky blueish.


Now this is getting even more confusing!

 

[steve20]

the red putty is for use after you sand the bondo. It fills in the tiny air bubbles, imperfections, and any sanding marks. It takes several hours to dry, and leaves the best finish you could want. In my body work days, we used to coat all of the bondo areas with a skim coat of the red stuff and sand with 400


Steve

 

[eljefino]

Originally Posted By: SOHCman
Thats interesting, I used some bondo last year and it was a grey putty you mixed with a BLUE hardener, and it dried sky blueish.


They have different flavors, maybe you got UV hardening.

 

[tom slick]

Originally Posted By: SOHCman
Thats interesting, I used some bondo last year and it was a grey putty you mixed with a BLUE hardener, and it dried sky blueish.


Was it 3M body filler?

 

[mechtech2]

By 'red hardener' do you mean the spot putty type of filler?
It is only thick paint - lacquer. It dries hard and brittle - no flex.

 

[SOHCman]

Originally Posted By: tom slick
Originally Posted By: SOHCman
Thats interesting, I used some bondo last year and it was a grey putty you mixed with a BLUE hardener, and it dried sky blueish.


Was it 3M body filler?


I will have to check, but I am almost sure it was that quart size can of bondo from WM with the plastic bowl like cap containing the hardener tube.

 

[SOHCman]

Yup, it was bondo alright, bondo "ultimate" which advertised a lower tack formula or something than regular bondo?