Hammer and Dolly lesson??

[prg machine]

I have a situation to share and maybe help others out as well as I figure this out, with the members help on this forum of course.

I am in the process of deleting the sidemarkers on a 68 front fender. Both right and left eventualy and the fleet bed as well. To start I chose the right front because it the usual rot at the front corner and also had about 2 quarts of bondo on it from an unexplainable series of dents and wrinkles that cover the whole thing. It looked good when I purchased but alas.......definetly in need of lotsa hammer and dolly etc. The fender is stripped and I have good access front and back. I figure the "bondo bucket repair" was done as a quick fix while the truck it came from was together. I have been guilty of similar " good enough for now " repairs in the past and can't pass blame on to anyone on this.
I ahave done a pretty good job of getting a lot of the dents straight so far and proceeded to delete the side marker. I cut a corresponding piece to fill with and was very careful to get a good fit to remain flush and not have gaps causing pulling and distortion when welded in. I tacked , hammered and cooled with air to not get too hot. As I proceeded the patch wanted to grow up and buckle . I carefuly peened out with hammer/dolly and caught a few more tacks....etc. etc. until all welded. The patch turned out good and fairly flat...........HOWEVER!!!! I now have a hand size concave area about a 1/2 inch deep at the deepest above that patch. It is spread smoothly out and is not straight forward to me how to proceed here. I tried a couple of heat shrink spots at the lowest area, heat a dime size spot red and then chill with compressed air. It seemed to be working.............BUT I stopped because I am now getting other distortion adjacent to the depression. Should I hammer dolly in a particular area?? On or off dolly?? I have no problem with the smaller stuff and even have removed very tight creases at the eyebrow area with only hammer and dolly.
Some wisdom is in order on this one as I feel like I might end up chasing ghosts and end up with another BOBDO Bucket repair. I realy wish to avoid this!!!!
Help????

[krue]

May need to move this to Paint and Body, but if you want some good reading try some of the threads here. www.metalmeet.com

[69RAT]

try ice instead of air! I keep ice in small bags just for that, canned air is to cold to quick.

[GREASEMONKEY72]

get some dry ice and a hiar dryer, heat up the dent with the hairdryer and hold the dry ice on it and it should pop out

i havent done this myself but ive heard it works

[stllookn]

Need a picture. Is it "oil canned"...will it pop both ways...in and out? If it is one way only and "in" it sounds as though the metal is stretched. Shrinking might bring it back...but so will heat (enough to get it red) and then use a flat spoon on the high side and hit it with a hammer to lower the high spot. I have tried to heat shrink using small spots like that but it takes too stinking long for my taste...I just use a rose-bud on my oxy-acet torch and use a slapping spoon on the high spot. Then I go back to the hammer and dolly for the small work. Get it within a 1/16 and skim coat it.

[bad6772]

this is almost impossible to answer without at least seeing the metal or feeling it, there are so many technics to shrinking metal, i would agree with 69 rat to a point, compressed air will probably get the area cold enough but to fast , i have used ice in a siplock bag wraped on a towel. there are ways of shrinking without heat. there are shrinking dollys, hammers , one thing i would defanitly not do is use a torch and heat sheet metal till it is red or glowing. unless you are experianceed with sheet metal..with patiance a good heat gun will get the metal hot enough and is more controlled. like i said it is hard to determine what is happening without acutally feeling the panel. at least for me anyways. i do how ever wish you the best of luck....... oh the oil can effect can suck. i fight that on a weekly basis on all this jap crap i deal with a work . oh pretty much every thing on the road has a little bondo or at least metal glaze like stllookn said ,try to work the metal to close as the contour as you can .good body starts inthe metal work, just anout anybody can wipe mudd on and sand

[prg machine]

Just got back from vacation.
Yes, hard to deal with not even seeing it I am sure. I will try some of the above and report back.

[prg machine]

Went after it again last night. Bigger hammer, heavier dolly.Pounded from inside and worked around it with heavy off dolly. Got it better. Now lotsa smaller stuff. More pounding!!!!

[prg machine]

worked on it again last night and remarkable discovery. I turned the fender 90* and worked it out in that direction. Was working front to back..............BUT (Duh!) stresses are omni-directional so now that I am also working top / bottom things are moving along a lot better.

[prg machine]

I have learned more on this fender about working metal than I ever knew! The best thing I have been advised and am doing ias the guide coat. I was using a rattle can black, but it was gummy to hit with the sanding board. I now have mixed up some Rustoleum red primer about 1:5 with mineral spirits and just brush on a thin coat. It sands easily when dry and a few strokes with a board and I find the highs/lows and work a few blows here or there and restroke the board and you can visualize instantly what your results( or mistakes ) are. Tracking every step of the way makes for forward progress. Try it next time you have to pound out dents. I have also done some improvising with an old splitting maul for a heavy dollyand a few different pry bars and such to reach behind the supporting framework behind the fender skin and give a dolly affect to pound against.

[prg machine]

WOW! I checked my origanol post and realize that I have been at this for almost 2 weeks now!! Probably around 15 hours or so! Now I know why they make replacement fenders.