Maximum Filler Thickness
 

I have a question about the maximum filler thickness that manufacturers recommend. Many claim it's 1/4", which seems like an awful lot. When they make that claim, is that in a single pass, or in several layered applications? Doesn't seem like it would dry well in a single pass.

Re: Maximum Filler Thickness
 

I would assume thats multiple passes. When i spread filler i do a really thin coat at first. I highly doubt a 1/4" coat would cure correctly and would brake off the first bump you hit.

Re: Maximum Filler Thickness
 

The answer to this is probably gonna depend on the filler type[IE long hair glass VS. short strand chopped glass VS.plastic filler]. It also will depend on the type say Rage Gold by Evercoat may stand a little deeper wipe of filler than say a parts store Bondo brand knock off. If it is a reputable brand[like Evercoat 3M or Dynalite and so on] they should say on their website product info and you may find it there. I can tell you 1/4 inch is not real thick and filler has been used for a lot thicker applications than that. If you are needing to wipe much more than 1/4 inch of filler I would really suggest more metal work by either studs welded to the panel then pulled with a lever tool or slide hammer or by welding metal tabs or straps welded in the deepest part of the damage then pull with a come-a-long

Re: Maximum Filler Thickness
 

LOL, this is a funny ass subject.

First off, it's subjective in that where is this 1/4" filler and over how large an area? If you were doing some mashed up tight metal like at the end of a quarter around the tail light and you pulled a zillion pulls and hit everything up from the back and you had this mashed metal basically back into the shape of a quarter panel and tail light mounting and you needed up with a 1/4" here and there in small areas that you couldn't get to for what ever reason, that really isn't a big deal. If the metal was prepped properly, if the filler was mixed and applied properly, this isn't a big deal. That filler will last a life time, we will be dead and gone and it will still be there under the paint, no one the wiser.

But let's look at a different repair, a roof or hood with some vicious dents with stretched metal where the 1/4" bondo is covering three or four square feet, that is a whole different story!

On the extreme, I will forever have an example. From when I was 16, when I chopped the top on my truck, we are talking the thickest filler I have ever seen. :D I had no idea what I was doing when I gas welded across the roof and warped it horribly bad. I didn't know how to fix it and simply bondoed over it. I put two gallons of Ditzler 999 (yes that was the part number) before I even sanded it!

I checked it years later with a large C clamp vice grip out to the middle of the thickest part, it was an inch and a half thick!

It did crack, long cracks up on the top, but no one was the wiser, just looking at the truck it looked pretty good.

Brian

Re: Maximum Filler Thickness
 

It is referring the total thickness regardless of how many layers.
Manufacturers will stand on solid safe ground so they have a leg to stand on when a customer complains about their product.
It's always a good idea to read and reread the technical data sheet on all chemicals you are using. It's the information you have to know in order to use the product correctly.

Re: Maximum Filler Thickness
 

WORD! :metal:

Brian

Re: Maximum Filler Thickness
 

Another consideration is the location of the "excess". If it's going on a door, trunk lid, or hood that is going to see some slam closing (especially given the extra weight), then try and limit the filler in these areas.. Here's how not to do it, This picture is from Old Soul Speed & Custom on IG, they are now fixing someone else's work... also note the thickness at the door edge. They said in the thickest area it was 5/8 thick. :eek:

Re: Maximum Filler Thickness
 

Re: Maximum Filler Thickness
 

this picture pulled from another forum to show about those moving/swinging body panels.....and sometimes it's not just the door movement, but parts inside the door. A power window motor installed after the paint job on this one, and perhaps wasn't anchored well enough. The pendulum action of the motor produced a crack in the door's fresh paint finish, this is what was lurking beneath...

Re: Maximum Filler Thickness
 

Thanks for all the really great replies. I'm just getting into some body work on my truck and I am trying to read and learn what I can until some of my supplies show up.

Re: Maximum Filler Thickness
 

Hahaha the rings of filler make it look like woodgrain. How terrifying would that be?

Re: Maximum Filler Thickness
 

ok, so what about a few dings on the middle of a hood? I was watching a pdr video and seems I may do the same thing using a tool to try to massage a ding out from prying from the bottom but if I cant get it all out.... what filler should I use? I have some Rage lightweight filler but should I use something else due to the metal flexing during driving and shutting hood?

Re: Maximum Filler Thickness
 

Just regular old filler or a polyester putty like "Glaze coat" from Evercoat is all you need. The "reinforced" fillers like "Metal to Metal" http://www.eastwood.com/metal-to-met...h-hardner.html or "Everglass" http://www.evercoat.com/product-deta...art/100622/us/ are largely overused. People think they are a must for a number of reasons when they are SELDOM used in most shops, regular old filler like RAGE (one of the best) is going to out last us, we will be dead and gone and it will still be there.

Most "show cars" you see are completely coated in a filler like RAGE, over the hoods, doors, roofs, and it will stay there forever. The reinforced fillers are awesome for something like a fiberglass repair to coat the area before regular filler is used to fine tune it. The Metal To Metal to use in a door jamb or something on an edge, yeah I guess so, honestly, I haven't used it in 25 or so years. But Everglass, awesome stuff for working with fiberglass.

Brian

Re: Maximum Filler Thickness
 

In addition to what Brian said :metal:, I'll add that the main differences between a body filler and finishing putty is both the size, quality and the amount of talc used to make them. The resins are similar chemically, but are also slightly different as well. The result is a that finishing putty or "glaze" is finer, smoother and more dense than filler but also softer to sand allowing finer sand paper which in turn reduces the chance of sand scratches. The reduction of sand scratches in the glaze, allows for less high build primer needed... and so on and so on...

Bottom line is metal is best for HB primer, second is glaze, then filler/glaze. Like most other things in life, filler and glaze included, moderation is key.

Re: Maximum Filler Thickness
 

cool thanks! So the Rage lightweight will be ok? The truck will be black so any waves will be highly visible

Re: Maximum Filler Thickness
 

Definitely looks like wood grain! Sort of impressive that they got what looks like 1/4" or better in only a few coats

Re: Maximum Filler Thickness
 

I was told it was about 1/2" or more thick.

Re: Maximum Filler Thickness
 

Rage is a very good product as is there glaze, Metal Glaze.

Re: Maximum Filler Thickness
 

is putting Rage on bare metal before a 2k epoxy primer ok? Or is the 2k epoxy primer before the Rage better?

Re: Maximum Filler Thickness
 

Epoxy is for bare steel as it's a corrosion inhibitor.
Filler goes on top.

The technical data sheet for both products will give you more details.

Re: Maximum Filler Thickness
 

awesome! I got the 2k primer in an aerosol can where you have a button to activate the hardener and it gives you like 5 hours to spray. I guess i'll wait for a good 75 degree day, spray the 2k primer then start my Rage filler to smooth out the area. Supposed to be in the 70's thurday and Friday.

Thanks for the advice!

Re: Maximum Filler Thickness
 

Re: Maximum Filler Thickness
 

Gear down there Big Rig! :lol:

You are getting primers confused... there are two kinds of primer 1) epoxy primer 2) High Build (urethane) primer

1) Epoxy is meant for corrosion protection and only intended for bare steel
2) Urethane High Build primer is meant to "build" so you can sand it down to make a smooth and straight surface.

Both of these products are 2K or 2 component. The aerosol picture you provided should be a Kwasny or "Spray Max" product as they are in fact producing a true 2K aerosol. Their epoxy is good for about 5 days once activated. The Urethane primers that they have are either the rapid or regular and they have a much shorter "pot life" of a day or two at the most. All of the Spray Max products are body shop quality and would rival any major paint brand's 2K epoxy or urethane high build. They are just really pricey. The added benefit of using their products is the spray can sprays just like a primer gun!!!

First put on the epoxy primer, then body filler. Sand and recoat filler as required. The high build urethane can be used to cover the filler, the bare steel surrounding the body filler and the epoxy. The bare steel around the filler is a result of sanding the filler and it is okay to high build prime this area without epoxy primer.

Re: Maximum Filler Thickness
 

I got the Spray Max 2k epoxy primer in a can... I plan to spray it on my bare metal area's on the some doors I did some shaving on. I thought the test video said good for 5 hours once activated. When I get home i'll check the label info. Either way though, I hope to have everything sanded and ready by the 70 degree weather coming on Thursday and Friday to spray this primer...good to know I should have more than 5 hours to use this stuff once activated. The pic was for an example. Its off of the Eastwood site. I posted it because there might be someone else that reads this and might need to buy a can or 2 to do small areas like I am. $22 a can is cheap and easy if you just have a small area to spray. Thanks again, Foot Stomper!