Bondo Body Filler

Post Reply
o1Marc
Posts: 8577
Joined: Thu Jun 03, 2010 1:35 pm
My Location:
Location: Dawsonville,Ga.
Contact:

Bondo Body Filler

Post by o1Marc » Fri Mar 01, 2019 6:30 pm

So for years I've been hearing about how Bondo will crack and pop and not stick to the substrate when heated. I assumed, correctly, that this was a bunch of BS. So I decided to do a test. Took a 5" square of sheet metal, whacked a big dent in it with a hammer and then proceeded to fill it with Bondo. Sanded it just a bit and then proceeded to coat it in a Matte Black. No popping, cracking I see no issues at all related to the filler. I would recommend if you are going to use it, that it be limited to very thin coatings. People say it has to be metal to powder coat. Not true. I have powder coated carbon fiber wheels, rocks, wood, glass, etc. If it can be heated to 400, it can be coated.



Says my pics are too big, take my word for it.

Miller821
Posts: 127
Joined: Fri Sep 07, 2012 9:39 pm
My Location: Carbondale, IL
Location: Carbondale, IL

Re: Bondo Body Filler

Post by Miller821 » Fri Mar 01, 2019 9:51 pm

No bubbles?

I wonder how it works on multiple coats. We've tried the EpoStrong from Tiger and have had hit or miss results. First, you can't build it up very much, and second it tends to work on a single coat, but multiple coats of power (Primer and Color) it seems to push out bubbles.

We'd really like to find something that can be built up if needed. Might have to give it a try.

o1Marc
Posts: 8577
Joined: Thu Jun 03, 2010 1:35 pm
My Location:
Location: Dawsonville,Ga.
Contact:

Re: Bondo Body Filler

Post by o1Marc » Fri Mar 01, 2019 10:14 pm

JB Weld is my go to filler, but it's expensive compared to Bondo. I did the test to see if I can do the finish coat in Bondo and not JB. JB only comes in 2 sizes, 1oz. and 5oz. At the parts stores the 5oz. is $20, but on line I get it for $10. I'll post any real results I get when I coat my bus doors.
So far no bubbling.

Miller821
Posts: 127
Joined: Fri Sep 07, 2012 9:39 pm
My Location: Carbondale, IL
Location: Carbondale, IL

Re: Bondo Body Filler

Post by Miller821 » Fri Mar 01, 2019 11:02 pm

So JB weld holds up too? Is there a certain one that does better than the other in it? I don't mind spending a little bit on it, as long as it holds up.

o1Marc
Posts: 8577
Joined: Thu Jun 03, 2010 1:35 pm
My Location:
Location: Dawsonville,Ga.
Contact:

Re: Bondo Body Filler

Post by o1Marc » Fri Mar 01, 2019 11:16 pm

Duke will tell you not to use the Kwik Set JB Weld, but i've had good results with both it and the original.

User avatar
duke46
Posts: 11334
Joined: Thu Jun 03, 2010 9:32 pm
My Location: East Coast NC
Location: New Bern NC
Contact:

Re: Bondo Body Filler

Post by duke46 » Sat Mar 02, 2019 4:37 pm

o1Marc wrote:
Fri Mar 01, 2019 11:16 pm
Duke will tell you not to use the Kwik Set JB Weld, but i've had good results with both it and the original.
The Kwik Set is not rated as high temp wise and the normal JB Weld is. So I have never tried it.

I have used in the past a bondo product that is rated above 400 and it did fine. But never just a normal bondo? They make all types of it so it looks like what Marc used worked and now for him to share what type he did use? The nice thing about it is the hardening up factor apposed to JB Weld even though you can speed it up some after it has set for at least an hour and then bake it at 150 for an hour.

USC All Metal will take the heat very well but make sure this is the one you buy because there is one all metal made by a different company that is not made for that high of heat, This is the one to get and you might be able to get it through CARQUEST Like I did or maybe even a NAPA store?
http://autobodystore.net/Merchant2/merc ... ry_Code=FM

As with any product that has an activator always make sure none of each gets into the other part and if it does then it will in short time make it un usable for sure :(

When mixing any type bondo then do it slow and easy so you can cut down on the little air bubbles and if you do you may have to us the JB to smooth it out. JB smooth's itself out really well :D
All I have said is said just for meanness so I don't have to argue with anyone!

http://www.pcitdad.com" onclick="window.open(this.href);return false;

o1Marc
Posts: 8577
Joined: Thu Jun 03, 2010 1:35 pm
My Location:
Location: Dawsonville,Ga.
Contact:

Re: Bondo Body Filler

Post by o1Marc » Fri Apr 12, 2019 11:21 am

The Bondo was a complete failure when the thickness is more than minimal.

Post Reply