Filler after Primer??

Kroll

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Morning,well I have been priming the Lux mill and notice that I miss some areas with the bondo.My eyes are not the same anymore,so what I'm wondering if there is a filler that can be use over the primer to fill small divots?Then apply one more coat of primer.I know I am trying to take a short cut so shame on me----Tks Kroll
 
Yes there is. Many are called glazing. There is the old school lacquer type and newer catalized type that mixes just like the bondo and dries much faster than the lacquer type.
Sands much easier than the bondo to.
 
It has always been my understanding that filled can be used on bare metal or over primer. You just need to make certain that you scuff the primer so that the filler has something to bite to. Fill ... sand ... re-prime ... then paint.

If the spots to be filler are shallow ... might I suggest using a glaze putty as your filler. I glaze filler is smoother in texture and usualy has less chance to leave pinholes. It all depends on what type of finish you are aiming for. If you will be painting with a brush ... then I don't think it matters what filler you use ... but if you are spraying ... or want a car like paint job ??? It is kind of like machining tollerances ... is one thou good for this project ... or just about any clearance is close enough?

Instead of shopping for your filler/paint/primer/materials at the big box stores ... if you go to a specialized body shop materials store ... you will find all the materials you need ... but more importantly ... you will find people with real world knowledge about the subject and they are usually happy to help out with any querries that you may have.

As far as brands of materials ... well ... that's like talking about who makes the better truck ... it is anybody's guess. Most any proffesional brand of filler will do the job. I use Sherwin Williams products ... but that is because they are the closest to my home. I believe that the ''BONDO'' brand is 3M, but maybe you were using bondo as a generic term for filler?

If you do decide to go visite a specialized shop, bring the primer information that you have used. That way, they will have the information needed to make the correct call on what products you should be using with that primer, because some paints don't like certain types of primers etc .. Your materials need to be chemicaly compatible.

Now that was a long winded answer to your question ... sorry about that ...
 
For the small imperfections I use the lacquer glazing compound.Apply it thin as it does shrink a little when dry. Allow drying time.
The quick hardening stuff is good toobut limited work time. Lacquer is always ready to use and when the stuff id applyed thinly it dries plenty fast. And I like the smell while it pickels my brain. ;>)
 
HI KROLL,
Something to think about, the car restoration guy,s that do high quality work
are using a 2part primer under the filler. The reason is the fillers are hydroscopic
and if not finished over right away, you get rust under the filler. And a failed
body repair a few years down the road. From my understanding all auto fillers
are compatable with all auto primers, spray can stuff you are on your own.
Also hardware store primers and paint.

So the best thing is to check with a real auto paint store, NOT NAPA ect. For
filler compatability with your primer that you used.
I have been putting 2part primer under my fillers for about 12 years on autobody
and no problems.

Take care,
Rick
 
Thanks guys for the input and Rick I never though of it that way and it makes sense.Yrs ago I did just the opposite and on my little 86 Ranger well you guess it the bondo came off.Rick is the steps to take is once the metal is clean primer first then apply the filler(bondo) and the glazing where needed?Then a second coat of primer????I just want to get it right to where yrs down the road I will have no paint failures.By the way I did use the glazing in those small divots and put the finish on today,guys its as smooth as glass.tks----kroll
 
Kroll,
Yes that is what I found has worked the best for me and others that I mentioned.
Metal prep, primer, filler, primer, finish coat.
The filler adheres to the primer just like the finish coat, putting filler on bare
steel seems like finish coat on bare steel. And yes every time I removed old filler
it always was rusted or loose. If it was over primer and primed over it was
always intact and NEVER loose or rusted. You had to grind to remove it, not pop
it off like when it was on bare steel.
I have not used a solvent based glazing putty for over 20yrs. I use a ultra thin
2part glazing filler that is for a lack of words, ultra thin fast set bondo.
You never get edge bleed 2 weeks after you finish like with solvent based glazing
putty.

Hope this might help.
Take care,
Rick
 
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