How Much Filler is Too Much

[draser]

So, I guess I'm repeating this post, in a manner of speaking, as I posted this on the old forum right before closing. Why am I posting this... because I believe it applies well to tank repairs where there may be deep dings (my experience) with no access to push from behind. Since I worked on several gas tanks, I noticed that, even with using the rods (customized to specific tanks) to push the metal the access may be limited due to the baffles inside. For large areas other techniques can be used to pull metal out so minimum filler is needed (1/8" sounds good) so this technique I'm describing is for small areas that are relatively deep and can't be accessed from inside the tank (through the gas filler hole).
Now, I've seen examples where a lot of filler is used, and granted todays fillers are very forgiving, but a good metal body work practice is to use minimum possible, 1/8" being a good target.
Basically, the ding area will be filled with solder instead of filler, which requires the metal to be clean (just like using regular filler). Also needed are a gas torch, solder and flux, all Home Depot items that I have handy.
Below are several pics of phases of the tank repair:

1 - damaged area filled with solder, and initial surfacing with a file:


2 - another area corrected:


And, of course, the surface will be smoothed out with filler, sanded, primed and painted, until the (almost - before clear) final product looks something like this: