1973 front bumper - paint

[J P.]

I have read past threads on this subject but still have some questions. My frt bumper fell apart in pieces the other day. I have a new GM bumper (cover) that I purchased from GM back in 2011. This bumper is gray in color not black like the earlier bumpers. My car was painted with a dark gray primer about 2 yrs ago. I am not ready (cost) to have the car painted now.
Questions:
Can the new bumper be installed right out of the box? (the color does match the car primer)
Should it be painted in flex-primer (if there is such a paint) before installing ?
Is there any other treatment I should use before installing ?

Thanks Mike

[Mark E.]

Re: 1973 front bumper - paint

Are you prepping and spraying yourself?

If yes, work with your local paint store to choose a product line. Primer surfacers and sealers will either be formulated for flexible panels, of they have an additive. The line will have a flex agent for the paint. Use one brand for all products.

Prep and spray with the cover removed.

If hiring someone, they'll guide the process. But it's good to ask as a check.

[J P.]

Re: 1973 front bumper - paint

Thanks for the info. I was not planning to prep and spray myself.

[Christopher K.]

Re: 1973 front bumper - paint

Mike, great to hear from you,

You have to install the retainers to give it structure for painting but I think most painters like to leave it off/ loose for spraying because of the seam.
I'm going to leave it to the experts as far as Flex Agents or prep, as I'm sure it depends on the product.
Bottom line, I would check the fit with the body, but not bolt it up until painting.
Best of luck,

[Frank K.]

Re: 1973 front bumper - paint

If you paint it of the car no flex in the paint is needed! (PPG) If you paint it on the car Flex is needed. I did mine off the car and it came out perfect.Also dry fit it on your car and let it sit for a week then shoot it in the booth or out side .

[Mark E.]

Re: 1973 front bumper - paint

If you paint it of the car no flex in the paint is needed! (PPG) If you paint it on the car Flex is needed. I did mine off the car and it came out perfect.Also dry fit it on your car and let it sit for a week then shoot it in the booth or out side .

Why isn't flex agent needed if the bumper is painted off the car?

[J P.]

Re: 1973 front bumper - paint

Thanks Chris

Mike, great to hear from you,

You have to install the retainers to give it structure for painting but I think most painters like to leave it off/ loose for spraying because of the seam.
I'm going to leave it to the experts as far as Flex Agents or prep, as I'm sure it depends on the product.
Bottom line, I would check the fit with the body, but not bolt it up until painting.
Best of luck,

[Mark E.]

Re: 1973 front bumper - paint

To save $, some paint shops will not add flex agent since the customer may not notice any difference until an impact. So be sure to ask a lot of questions.

[Harmon C.]

Re: 1973 front bumper - paint

I made a jig to hold the bumper for painting out of plywood base with two by two inch uprights to hold the bumper for painting. The fit of the GM bumper is great right out of the box. Install the metal on the bumper before painting and use the studs to bolt the bumper to the jig in four places with small pieces of pipe strap. I have used it four times with no problems. I replaced the bumper on my 73 in the body drop at the National Corvette Museum when it fell apart in perfect storage conditions.

[Frank K.]

Re: 1973 front bumper - paint

As i mentioned prior shooting PPG and working with PPG off the car no flex. I used the primer then base coat and the clear . I shot it my self in my garage. But beware with paint shops because prep is the key to a flaw less job. If you enter a shop and it is grungy walk out. Select the product and make sure the vendor agrees! I am not a painter by trade but you can go on line and for example receive a lot of information . PPG is an example of a well rounded web site to look at.