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TR2/3/3A Anyone care to share their bondo applying techniques

sp53

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When I apply putty, I find that I only get about one pass with the spreader before I run into problems with build up. If I try a second pass with the same spreader, the film and build up left on the spreader from the first pass bunches up the putty and makes the first spread worse.

What I do is use a second or third or fourth spreader if I make a more passes to smooth down the putty more. Do people wipe the spreader with a rag each time or something? I thought maybe a rag with a little bit of lacquer thinner might be ok to get the film off in-between wipes because that evaporates so quickly. Anyways always up for new ideas.

steve
 
While we call all body fillers Bondo...sorta like we call all tissue Kleenex...it turns out the actual Bondo brand filler sucks to spread. Evercoat Rage Ultra is the best spreading filler you can buy. Once you spread it you will never buy bondo again. If you have very thin areas to fill, the thick filler is also not easy to get down to 1/8” or so without trouble. So, when you get down to very thin filling, switch to Dolphin Glaze.

There are other very decent fillers, but these 2 are the absolute best I have used. Bondo is the bottom of my list in every respect. I still use bondo occasionally, just because it is cheap, available absolutely everywhere, and I have many projects that need filler without being car finish quality.

Another aspect of spreading is to use the right amount of hardener for the outside temperature. Once you get the right amount, you should be able to mix for a minute, and have about 3-5 minutes to spread. If it lights off in less than 2 minutes, you fight the filler more than the project. Then, it’s a fine line from lighting off at 5 minutes, and taking an hour...or forever...to light off.
 
John is right temp is important and you may have to much hardener. two coats is better than one thick coat holes and rusted out require some playing around. welded patches might be best way to go. Thin and win. Madflyer
 
I also use Evercoat brand too. I also have one or two like new spreaders in my back pocket to even out the first application, if needed. I reuse them so always make sure the spreader edge is sharp and smooth, and wiped clean with lacquer thinner. Too much hardener and it starts to harden too quickly for a good result, but too little and it doesn't harden correctly, it's a fine line between how it looks and how well it holds.
 
I also tend to like the flexible metal (i have heard them called Japanese) spreaders much better than the plastic. They are usually sold in sets of 4 from wide the very narrow.

Cheers
Tush
 
Also keep in mind not to use "bondo" on edges unless it is a thin dress coat.
"Metaltech" or similar is best.
And use "Fine Fill" for final dressing of small imperfections.
 
Just to let you know the technical term for this stuff is body filler. Bondo has such a bad rap, that the industry doesn't use it anymore. One secret to good body filler work is to get a feather edge. Say you are filling a nickel sized dent. Apply the filler. do a ruff sanding before the filler has fully set up, maybe using a grater. finish sanding should be always at right angles to the edge. Don't try and go all the way across the filler. Small motions from the sheet metal to the center of the filler. Then continue in a circular patter around the filler. This is your best chance of getting a good result. Use an ungloved face of your hand to feel the surface. If you can feel the repair, it is not right.
Good luck, Scott in CA
 
I'll share the method my previous body guy used:

Blob the stuff on thick with lots of lumps. Make your high school son (who does not want to be a body man) smooth it with a rasp. Make sure he cuts into the metal and removes the all of material from the dent. Repeat the process. Try to understand why the client (for no apparent reason) took his car to another shop.

I've also used Evercoat Rage with good results.

Rod
 
Zero Bondo on this, only lead! (y)
Paul_J_Paul_J_000 (1).jpg
 
I agree with the Evercote above. Also, I hired a body guy who worked on the weekend for me. He put in very little catalyst, he wanted it to cure slowly so he could use the grater to file off the excess. The final coat was very thin. If I do have a place that needs more than 1/8 inch, I use fiberglass kitty hair in that area. That stuff is waterproof and will not crack.
 
Rule of thumb we use here in the UK for the ideal mix is a golf ball to a pea.

I have known people use too much hardner, ( here it is red ) I have known it to bleed through the primer
 
Another +1 for Evercoat "Rage" Besides being great to apply, it also seems to have very good shelf life if stored well.

With one of the (non-triumph) cars I used to have, I remember wishing that I could just spray pre-mixed body filler out of a hose, as is done with "shotcrete" to make elaborately-shaped swimming pools.
 
I have only been doing this professionally since 1971. The first and most important step
is the "working "of the panel itself. This critical first step dooms most repair jobs before the
filler is ever applied. If the steel is NOT dollied to a good standard and the metal NOT heat shrunk,
where necessary, to tighten up any "oil canning" its NFG.
The desired overall build depth of modern fillers varies by brand. 8mm is high. LESS is more here.
Generally ,if you have a fill depth that requires several coats to achieve, ya screwed the pooch.
On certain repairs(rust) exceptions can be made. After welding, an initial application of "Tiger hair". is good
Fiberglass is NOT subject to the type of cracking that unreinforced fillers are. This is ALWAYS done across ANY welded
seam.Fillers over a weld fail 99% of the time,clearly showing the weld line inside 18 months. The fiberglass
filler should be long strand and allowed to cure well before it is ground down lightly and filled over.
Practice daily for many years and it will come to you.
Mad dog
 
Thanks, Just yesterday, we were talking about welds on a Jenson Interceptor front apron. A little kitty hair first!
 
When i was working in the body shops, we had to have two seperate sets of tools.
Tools used on alluminium could not be used on ferous metals and vise versa due to contamination,
In the end it was found to be an expensive outlay for most panel beaters, so some body shops
had panel men that only worked on alluminium in there own segregated section of the workshop.
 
Ford recommends similar precautions. We always used plastic spreaders and changed them out.
Most of the American cars were steel any way. But Austin Healeys, RR, MGA had alloy panels .
Saved the front door on a 60 Silver Cloud a few years back. What a beast!!
Mad dog
 
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