Paintless Dent Repair

I am in the process of repainting my '86 500F. I've been prepping all the parts over the last few days and I was worried a bit about my tank. It's got ZERO rust inside and the paint has seen better days, so I was planning on repainting anyway. The PO dropped the bike on the left side and, of course, resulted in a dent about 3" x 4" x 1/4" deep, with two distinct knuckle indentations (musta hurt). Being the OCD type that I am, I didn't want to put that much bondo into the tank. You never know what's going to happen to it a year or two down the road with cracking or shrinking of the stuff. So I did some internet research on paintless dent repair (PDR) last night and watched a bunch of video. Today I went out and bought some stuff to give it a shot.

Well, I'll tell ya folks, this stuff works! I was amazed how well it came out considering the size of the original dent (see attached pic). There are some tricks of the trade these guys use to work their magic. One of the first things you need is some kind of flat board with lines on it. I used a dry erase board with strips of green painters tape. Using the reflection off the tank of the straight lines, you can tell whether you have a dent or dimple, and also use this to gauge where your tool is located when you use it in the tank.

Next, I used a 1/2" steel rod bent in a manner to get it in the tank and reaching the dent. This tank is NOT easy to get a tool into. I had to rebend the thing at least 10 times to get it to reach all the spots I needed to. I attached a rubber nipple and some duct tape on the business end to prevent sharp edges from dimpling outwards.

For dimples in the outward direction (which will inevitably happen when pushing back out from the inside) I used a 3/8" oak dowel that I sanded to a dull point at one end. I also used a 1/4" nylon machine screw with a flat end for larger work. Light taps with a small hammer on both these push dimples back in nicely.

Lastly, the one I was most amazed at was the effectiveness of dry ice and heat. It was the first thing I tried to get the dent out, and was unsuccessful, thinking I had just wasted $20 on dry ice. After using the rod, I was not able to get the majority of the knuckle dents out, and there was an area at the top of the tank I just could not reach. Like I said, this was challenging to get the bent rod to work. So I gave the dry ice another go and it started working. The dents just started disappearing! Frickin amazing! I then got out the hair dryer and started alternating heat and dry ice and it was even more effective.

What's left are three or four small, shallow dents that will be easily covered with a smear of bondo and finishing paste. Here's a pic of the results, which probably look worse that it really is. These are very shallow, and not bad at all considering what it started out as.

 

thanks for the good info, recently got a dent in my tank and was wondering how i was gonna get it out. Will give this a try when im ready to sand and paint it.

 

good stuff. for reference, the Ding King also works great

 

If it were a flat panel that you could easily get behind I'd have kept going until there was no sign of a dent, but having to go back and forth to the vice to rebend the rod a gazillion times was getting old, and I was satisfied with the results, the overall goal being significantly less bondo to apply. I also wanted to do this myself for several reasons, the main one being cost. I spent a total of $30 on supplies, the majority being the $20 on 10 lb (minimum purchase) of dry ice of which I used maybe 1/2 lb. The steel rod was $6, the wooden dowel $1.25. I'm a bonafied member of CBMMA (Cheap Bastard Motorcycle Mechanics Association) and this is a budget project.

 

That's easy! No welder! I'd kill for a nice TIG, or even a MIG, but I couldn't justify the money with the amount I'd use it.

 

BTW, almost forgot, I've come up with a paint scheme. It's an amateur Photoshopped version right now. Hope you guys like it....if not feel free to hold your comments for later. :tongue:

 

I heard about the dry ice thing.. may have to try that one....

 

Thanks for the info! I've got a dent in my tank from a tank slap that the previous owner didn't bother fixing before repaint.