Question is on the Elastomeric Bumper.

[72and86]

I have a FE 5 70 'Cuda 383 I'm doing body work /repaint on and I'm a newbie at this. My question is on the Elastomeric Bumper. My car has this option but the bumper needs very light body work as holes and tiny bits are missing. After stripping it of old paint and using Evercoat light body filler here and there, it was primed by my auto body friend with 4k professional primer, 2 coats.

I let it sit in my Connecticut garage over the winter, standing on end. It was untouched. In the spring I brought it out and found hairline cracks all through it! Did it shrink? My friend says he didn't use a "flex" primer and never has in 50 years of bodywork, without any problems. See pic. UGH. Im in the process of removing the primer now.

So how do you tackle this unique Elastomeric material the right way?
Thx Steve

[Chryco]

you need to use elastomeric material. to part epoxy. forget body filler. those cracks are deep. let me know if you have any other questions

[MoparLeo]

Chryco is right. You are working on  flexible material and conventional fillers and paint will crack. This really is best left to a body shop as all modern cars have flexible front and rear facias and they have both the proper materials and paints and experience. If it is an original bumper it is also 50 +years old and the material dries out and gets hard just like the dash pads do..

[JS29]

SEM makes a plastic parts repair system that works vary well, PPG makes an additive for there K36 hi build primer-serfacer for flexible parts. I have seen it repair parts that others gave up on.   

[72and86]

SEM makes a plastic parts repair system that works vary well, PPG makes an additive for there K36 hi build primer-serfacer for flexible parts. I have seen it repair parts that others gave up on.   

Any details on the SEM repair system? I couldn't find what your mentioning?

[72and86]

you need to use elastomeric material. to part epoxy. forget body filler. those cracks are deep. let me know if you have any other questions

Like this? https://www.ebay.com/itm/203900509454

I see a lot of elastomeric coatings for roofing. Is that stuff Ok? Or are you talking about hardware store 2-part epoxies? Thx

BTW: bought a new front e-bumper from you 2 years ago. Good stuff.

[JS29]

  @72and86  Sem products are sold at numerous auto parts stores that sell autobody supply's, I am sure  there are other brands out there as well.