Question about Bondo

[Newman39Fan]

So I decided to try out Bondo for the first time. Except for the fumes, I was pretty impressed with the results. I used it to cover the screw holes in the floor, which will be covered by peal and stick tile squares. So I was not as worried about the results, just trying out something new. Anyway I was impressed enough that I plan on using it on the rest of my build. However I do have a few questions.

Before building my TD the only thing I knew about Bondo was it was used for bodywork and to repair a pothole at Daytona. So I went to Wal-Mart to pick it up. I figured that would be easy, but no. They had “the original formulaâ€

[Lookfar]

The original Bondo works well and there is no reason not to use it. I used it on boats for years. Just make sure to seal it with either epoxy or polyester resin before you paint. Though you might get away with not sealing it with resin, it will insure that it doesn't break loose.

[glassice]

Out here Bond is $ 20 at wall mart if a car paint store is near by call and ask. I get dynatron x grip for $ 14 every day price and it has less clay in it so less shrinkage All bondo is polyester resin and some cheap feller . Bondo is the bottom in but what you are using for it will work .
when you use to feather out add a litte polyester resin about 4 are 5 % to your last coat will make it like a glase coat very nice

[parnold]

Bondo was a trademark name of Dynatron Corporation, who was purchased by 3M a couple years back, so technically any product with the "bondo" name is 3M. Lightweight filler has more microspheres, and is easier to sand than regular bondo, but recommended thickness is also less. For filling screw holes and minor imperfections, lightweight would be perfectly fine.

Regular Bondo is a little harder to sand, and you can put in on thicker.

Gold bondo, is simply an imitation of Fibreglass Evercoats Rage Gold. Fiberglass Evercoat is 3M's major competitor in the body filler market. Gold body filler uses more advanced resins, so it has the easy sanding qualities of a lightweight filler, but can be put on thicker like regular bondo.

Gold is a waste of money, unless you do this for a living, the main advantage is production time, for a body shop, the extra money pays for itself in labor savings, or at least that's what they want you to believe.

Now that I'm done with my body filler lesson, I would recommend lightweight because you will save time in sanding. Adhesion will be no problem as long as you topcoat with something to keep the moisture out.

[starleen2]

Used the regular bondo to feather the edges of some fiberglass tape and seal some screw holes and gaps - after a year of use in all weather extremes - no cracks or popping out

[caseydog]

I use just plain Bondo that I buy at Lowe's.

Here are some tricks I've learned through trial and error, that may help you.

1. Don't try to use it in really hot weather. It will set up in a couple of minutes, at the most. Temperatures in the 70s or cooler will give you more working time.

2. Overfill your voids by just a bit. Then, give it a day to harden, and take it down flat with a sander. Don't try to get a nice flat finished surface with your knife. Overfill, and sand down. The more time you give it to cure, the easier it is to sand. If you try to sand it too early, it will be a PITA to sand, and will not sand to a nice smooth surface. I always give it at least overnight to get good and hard.

3. Use a flexible plastic putty knife to apply it. That way, if it hardens on the knife, you can crack it right off the knife.

I just did a few cosmetic repairs on my TD a few hours ago, and used Bondo. I will sand it smooth tomorrow, and touch up my paint.

It really is easy to work with, as long as you know how to work it, and understand it's weaknesses. The biggest weakness I discovered the hard way, is that using it in the afternoon in July in Texas is nearly impossible. It is hard before you can spread it.

CD

[TwilightLane]

I love Bondo. The first time I ever used it was on my build. Fascinating stuff!

[Newman39Fan]

Thanks for all of the replies! Looks like I will stick with What I got and not buy a "better" version. I did learn by trial and error to over fill and then sand down. Only need one application that way. I tried to get to cute the first time and had to add more after it cured.