Body Filler Over Epoxy primer

I just Sealed the street truck i'm building with epoxy primer and than seen some small dings i didnt notice when it was bare metal is it safe to put body filler over epoxy primper or will it f*ck up my paint jop

thank for the help
Scott


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That's the way I always do it. My paint reps say it's the way to go because some types of bondo can actually absorb moisture and could corrode the body. I understand either method is acceptable though. I've never had any problems with this method with a few exceptions and I honestly believe it was because of the DPLF primer and not the methodology.

It will not hurt a thing and its the best way to do it!
Flyfisher is right that ALL fillers retain solvent and air and anytime you sand off ten year old filler there is rusting in that area.
But that not the best reason to do it! Filler or two part glazing putty or fiberglass fillers will stick to the epoxy better than the metal especially fillers like Tigerhair, Duraglass, Kittyhair, these fiberglass products do not like bare metal for a long term ride.
If that not enough the epoxy can actually increase the flexibility of these products, depending on the product up-wards of 75%!
(mostly because of the great adhesion)
These products will feather and sand better than over bare metal and also resist sucking up (showing your work) down the road on flat surfaces due to expansion and contraction, and this is normally blamed on primer shrinkage but not always the case.

I am interested in your last statement about epoxy and filler. I was thinking about doing this myself, but I have been concerned about what I have been reading about products such as DPLF not adhering well as they used too, and it sounds like you are not supposed to use filler over products like variprime (which I have ). To ensure good adhesion with the DPLF, I have been told to use a phosphoric acid base wash prior to spraying the DPLF, or put down an acid etch primer first and then epoxy over it. My concern with the latter is that if you sand through the epoxy while prepping an area for filler, could you have a bad situation with the acid etch primer making contact with the filler. How does someone get around this problem if it is one? Since I have an older car with some minimal surface rust under the old paint, is the vari prime the best for that? Would it work well to variprime everything, scuff it and then put DPLF over that for bodywork areas?
By the way, thanks for the ideas on my last post about trying to seal pinholes. It was a temporary set back that was frustrating. I managed to find a 1" diameter roller with a 24" handle that allowed me to get between the fenderwell and outer fender. Now I have POR15 with a layer of seam sealer in that area. I think the weld was better than I initially thought as well. I also managed to shoot a light from the inside out, and the weld looked pretty solid.
Kind of embarassing from a guy who has 18 plus years experience in welding and fabrication. Thats what I get for rushing things though. Everything I took my time on came out great and took about a day, and everything I rushed on came out #$%%@%..... and took about 3 days.

One other note. I should not knock this project that bad. I have sectioned the entire lower half of the body and a auto body friend is impressed with the work at this point. He is not the kind of fella to hold back a comment if the work is bad...trust me on that one! I attribute that to the help I have recieved on this board.
Thanks!

Ron,
Ist part of your question, yes Variprime is Acid Etch and no you can NEVER put filler over Acid Etch.

Do yourself a favor and carry the Variprime back to the jobber for a trade in. You don't need it or want it.

If an epoxy requires an acid etch to stick to metal, don't buy it because it serves no point and is a waste of money as the acid etch will now be the weakest part of the paint system as far as corrosion protection, total paint durability and life expectancy for the paint.

Duponts epoxy does not require anything to stick to bare metal.
Also at the same time take back the acid treatment.
Read the post a day ago about paint bubbles. If his paint still look good after ten years its garage kept, he has emailed me and I responded but have not herd back to know all the details.