Filler over bare metal or filler over primered metal?

[bandit67]

What do you body guys normally do. I got my metal patch welded in and now its time to add my skim coat of filler, so , I have ground down the welds and plan to apply epoxy primer over bare metal and then apply filler. Isn t that the preferred way instead of filler applied directly to bare metal. thanks...

 

[vintage chromoly]

Yes, epoxy over bare metal and then do your filler work

 

[91r/t]

I've done both.....both work fine. Did my major filler on the bare metal this time and then etch and build primed the entire car. Now I am doing my putty/icing work over the primer before I give it one more round of build primer and final block sand the car before paint. Just depends on what your plan is. If you are doing all the major bodywork in a few weeks like I did, I wasn't worried about rusting in my heated shop. If you are picking away at it over time, I'd prime it first, then do your bodywork so the metal is protected for the time period. I would hit the area with a good course paper once you are ready to do your bodywork either way so you were close to metal as the fillers are designed to go over metal or a bare substrate and have a good "tooth" to bite to like 36-80 grit scratch.

 

[bandit67]

Well, just filler over the bare metal would be the simplest as mixing so little two part epoxy to cover about a 9 inch square area will prollly be a lot of waste . BUT, I do not want anypart "lifting or "bubbling up" in the future. Have that on a hood I done a while back and wonder what I did incorrectly to cause that to happen....thanks..

 

[91r/t]

Oh ok I thought you were talking whole car not just an area. Yea going over bare metal with filler shouldn't be your cause as to why it lifted. Make sure its got a real good scratch to bond to and clean the **** outta it and it should be fine. I've seen it happen in both cases and I don't think there is a perfect explanation for it or one answer. So much **** can go wrong on different metal areas with materials, cleaning, product failure, LUCK......it can suck for sure.

 

[Builderguy]

Depends on what filler you use. Mine says to apply over BARE metal, so that is what I have done for several years now.
I have used the same brand filler for all those years and have not had any problems. When they make a better filler I will try it and maybe switch. My jobber wants me to try RAGE Gold, I think, maybe later as I still have about 3/4 of can of filler left and that goes a long long long way.

 

[91r/t]

Depends on what filler you use. Mine says to apply over BARE metal, so that is what I have done for several years now.
I have used the same brand filler for all those years and have not had any problems. When they make a better filler I will try it and maybe switch. My jobber wants me to try RAGE Gold, I think, maybe later as I still have about 3/4 of can of filler left and that goes a long long long way.
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Rage Gold is the ****!!! Sands off like butter and is so nice to spread!

 

[GMP440]

Rage Gold is excellant.

 

[Builderguy]

Okay, next can I buy will be Rage Gold. The TDS for Rage Gold also says it can go over bare metal.

 

[bandit67]

I just ordered a 3 liter can of Rage Gold......prolly end up throwing a lot of that away....just how long does a can last once opened.....

 

[Kern Dog]

Close it up and keep it out of extreme heat or cold and it will last quite awhile.

 

[forphorty]

The hardener goes bad much quicker than the filler.

 

[RGAZ]

The hardener goes bad much quicker than the filler.

You can buy the hardner seperate cheaply from Amazon. It does dry out first.

RGAZ