I Admit Defeat

[Joe Flanagan]

This one's got me totally beaten. There's a dent in one of my fenders. I tried to work it out with hammer and dolly and I got it close but when I applied filler, I found that I had a few high spots, so I started trying to work them down. Well, here it is a few days later and I still can't get it right. I work the dent to the point where there are a few minor high spots--still too high for filler--so I try to work out the minor high spots and the whole thing oil cans on me. I heat shrink it and it stiffens up again. I try to work the dent some more and it oil cans again. Repeat cycle. The dent will sometimes go concave with a few high spots around its edge. I try to work those out and I wind up convex again. Anyway, here is the area:

I've tried everything I can think of to get this right and I haven't been able to do it. At this point, I'm considering cutting the area out and welding in a new piece of sheet metal.

Any ideas? I'm totally stumped.

[Rodney Bullock]

Hey Joe, that metal looks weak It might be better to cut it out and weld in a nice freash peice. You have beat the heck out of that, oh happy Fathers day:) I was going on a Dounut run this after noon and though of looking in on you. Some of my wifes friends came by and had to have a tour of the 41 Stude. I now regret it because I want some dounuts:mad:bad real bad.

[Flatie46]

I'm not much of a bodyman and this may be a dumb idea but...What if you welded something to the backside to keep it from oilcanning and maybe it would hold shape when you pecked the high spots down.

[greg g]

Sometimes you just gotta whack it down, then put the filler on top, unless you want to cut it out and replace with new stuff.

[Plymouthy Adams]

Joe, have you tried to drill out the center..work it to the right contour..fill weld and grind flush..odds are the metal is so stretched from work it needs some relief..

[randroid]

Joe,

You and I are probably near the same level of experience in metal bending and since I've got a dent I've been pushing out I'm watching your post with interest. I haven't gotten around to annealing it yet (that's the actual metallurgical term for what we more conveniently call 'quenching') because I only work on my cars on days when I won't be waiting tables and that cycle doesn't come around again until Monday. I'll do some more pounding then, getting it as close as I can before quenching, then do it again, but metal fatigue is in the back of my mind. Know how you can bend a coat hanger back and forth until it gets hot and it seems as though you can see the crystaline structure in the bend just before it breaks? That's fatigue, and once it reaches that point there isn't enough annealing around to make it right again, which is what makes me think the idea of replacing the metal with the dent might be the route you want to take.

I was training a new waiter tonight as he's worked for a corporate chain in the past and doesn't realize he was originally trained (if at all) under a set of rules written by people who've never waited tables. At the end of the evening he commented that I took twice as many table as he had (we were slammed) yet he was working his @$$ off and couldn't have taken another table. I countered that perhaps he should listen more closely to how I tell him he should do the job, which is doing the same job more efficiently. Okay, that was some venting on my part, but the point is that we're tyros in metal bending and we haven't learned to do it efficiently yet. We'll get it if we keep looking for a more efficient way of going the same job, like only needing to anneal it once and realizing that anymore hammering will only damage the metal. You and I are busboys in metal working and we want to be the Maitre 'd overnight, but that ain't a-gonna happen. I don't have too many dents but I'll bet a dollar to a donut the last one will be sweeter to finish.

Hang in there, and please keep posting updates; you have a student out here who wants to learn.

-Randy

[Joe Flanagan]

Thanks for all the responses. Tim, if I drill out the center, how big a hole should I make? I posted this on the auto body site that I frequent and they believe, like some of you, that the metal is way overworked. I know that if I cut it out and replace it with new, it will take much less time than me trying to learn my way through it. Randroid, I get your point about the metal fatigue. It may be that there isn't anything to be done at this point. What's really weird is that I know that the metal is behaving in a certain way but I can't figure out why. There are high spots that won't respond to any tapping. So I increase the force of my blows and then the whole section oil cans. It's almost like there are areas where the thickness of the metal is greater, like it's lumped up in some places. Anyway, it's 7:30 AM here, and I'd like to make some progress today. It's too early to make noise, so I'm going to research it until about 10, go out and try Tim's idea of drilling out the middle, and if that doesn't work, out come the welder and the cutting wheel. Thanks again, everyone.

Rodney, have fun at Sully.

[Joe Flanagan]

So I wound up cutting the entire area out and replacing it with new metal. In the process, I managed to create another oil can above the new piece. I messed around with the torch and a wet rag, just trying different things to see what would happen. I tried going around the entire perimeter of the oil can with quick bursts of heat, followed by quenching. That fixed the oil can. It is now close enough for filler. I haven't finished welding in the patch, though, and I'm worried the heat from welding might create some other kind of problem. I can't wait until this is behind me. I have yet to find a really good description of heat shrinking anywhere, something that tells you exactly what to do, where to heat, where to hit, etc. Seems like every source explains it in a different way and very little of it makes sense to me. I understand the physics of it, but how to put that to practical use, no. Anyway, I'll finish welding up the patch tomorrow and then see what happens with the filler.

[Rodney Bullock]

Anyone else here think if Joe applied his mind to it could solve the problems in the middle east:) He is the poster child for determination. I can't imagine the day when Joe goes into his insurance agent to get coverage and the agent asked" So what do you think your car is worth" Joe will grab the guy around his neck and say" How much you got" It's going to be very scary:eek:

Good work Joe, cutting out that section was the best thing.

[Jim Yergin]

I agree with Rodney. I for one find the name of the author and the title of this thread to be a complete contradiction in terms. Joe Flanagan defeated?

Not in a million years.

Jim Yergin

[greg g]

When I placed metal patches in the studebaker, I just tacked it, the seam sealed it from behind. Not real craftman like but certainly strong enough for a fender, used some panel bond where there was nothing to weld to.

Edited June 22, 2009 by greg g

[1947PLEVY]

Joe:

I'd use a wire welder and just tack about 2 inches apart until it's welded not letting it get too hot. Kick back drink a cold drink and use your better judgement. As far as "DEFEAT" goes...NAH!!! Just a small bump in the road. Smooth sailing one day..

God Bless Us All..

John 47Plevy

[Joe Flanagan]

I'm using a wire welder and doing just that: Tacking a few places around the patch and then giving it plenty of time to cool. I think the repair will work. I don't want a wavy finish in the end, so I'll do whatever I can to make it right. Hopefully it will work out. This is just learning as you go. I have a lot of pieces in bare metal and I want to get them painted. Unfortunately, I don't have the time to learn the finer aspects of metal working. The piece I mangled was beyond me. I know it was fixable but I didn't have the experience to do it.

[greg g]

Joe if you have bare metal pieces, check your hard ware stores for a product called The Must For Rust. It basically a home owners version of the stuff body shops use called OSPHO. It Phosphoric acid soultion with an ingredient that leaves a coating on the metal.

You can get OSPHO arround here from body shop supply places for about 35 bucks a gallon, the stuff in the hardware is usually 10 to 12 bucks, fo a spray quart actually a much higer price by volume and with my next purchase I would have been even with the gallon price.

But you spray it on, let it sit for a while then wipe it off or let it dry in the sun. It will etch the metal, getting the rust out of the pin holes, then it leaves a protective, sandable and primable coating the will keep surface rust off for a year or longer for stuff stored inside. It also gives primer a really good bit on the bare metal.

http://www.dtep.com/mustrust.htm?gclid=CMjwn--LnpsCFQdN5QodsXxIoQ

[Joe Flanagan]

So after a few days of struggling with my fender, I'm still close but not good enough. There are high spots that I can't get to come down and low spots that will need to come up, which I think I can accomplish. From what I have learned, high spots need to be shrunk down, which I have done. They shrunk a good deal, but then as I continued, they seemed to actually get higher, which I interpret to mean that I am overshrinking. At this point, I'm just trying to tap the high spots down without causing any more damage. The surface of the fender is supposed to be perfectly flat in a front-to-back direction. I put a straight edge on it and I'm really close. Just those few nagging high spots that won't come down. I think I might be going too easy because I'm skittish about undoing the work I've done. The weird thing is that even though the straight edge tells me I'm almost perfectly flat, when you sight down the surface, it looks really wavy. Optical illusion I guess. Anyway, here are some pics:

[Plymouthy Adams]

Joe..in tapping the high area are you using a shrinking hammer with the dolly?..else you are probably expanding the metal..frustrating to no end I can assure you..

[Joe Flanagan]

No. I'm using a regular body hammer. Should I be using a shrinking hammer? I assume from your post I should be. Have you ever tried to shrink a high spot down only to have it come up higher? Can't figure out what's going on, whether I should keep trying to shrink high spots down or try to hammer them down.

[Plymouthy Adams]

hammer and dolly work can get you in trouble as fast as it can get a dimple out of the car..a shrinking hammer will help in the working of the high spots..how big of an area is high? oft times a small pick will do a dimple and reasonablily small high spots..is this spot an area you can use a shrinking disc..much better control of heat and pressure applied to work the metal back to normal..having access from both side makes this even more of a ease...there are times Joe that you can reach only status quo and it is best to cut your loses and move on..if the area is relatively small and the filler used will be only slight for skimming an imperfection per say..one may have to suck it up and go the alternate route..having solid backing to the filler is more important at this time..next time you get the area to low...test the contour for filler depth you will need..I know it is not always what you want but I assure new cars have left the factory with filler..

[Joe Flanagan]

Tim,

The area that's high is in the shape of a rough oval, about 4 inches tall and 3 inches across. The panel is supposed to be flat and when I put a straight edge on it, the straight edge touches the high spot in the middle and the ends of the straight edge are off the surface by about an eighth of an inch. Believe me, I am with you on cutting losses and moving on. But at this point, I think the high spot would show through the filler and I don't want to mud the whole thing only to find out I need to rework the area. I also have some dips I'd like to pull up, but I'm not worried about that. It's the high area that is giving me fits.

Now, I must confess that I've been trying to do this job with a standard body hammer and a slightly curved dolly. I went to Harbor Freight this morning and bought a slapping spoon and a couple of dollies, one of which has a flat surface. If I can get the highs down and the metal is firm, I'll be good with some filler.

[Joe Flanagan]

Well, I'm still at it. And I don't want to jinx myself but I think I have the problem solved. I finally realized that the distortion in the sheet metal was due to a patch I welded in. When the metal shrunk with the heat of the weld, it pulled on the surrounding material and made it kink. Not realizing what was happening, I tried to straighten it out with a hammer and dolly, to no avail. I tried stretching, shrinking, nothing worked. Today, I heated the weld seam with a torch and hammered on dolly, stretching it out. Then I stretched out the entire area I'm working on so I was starting with a known quantity: Everything stretched, no kinks, dents, shrunken areas or anything to add any mystery to the equation. Then I got out a shrinking disc and started shrinking the whole area down. It has taken a long time, but everything seems to be working out. High spots that wouldn't budge have come down. I worked with the shrinking disc until I ran out of light. I still have some work to do tomorrow, but I think I might have it licked. I've learned a lot from master metalworker John Kelly, who works on Karmann Ghias. He's got videos that you can access on YouTube. We've been e-mailing back and forth and he's helped a great deal. Obviously, I never expected to get sidetracked like this, but that's the nature of these car projects. I really hate to just bring it to someone and say, "Here, please fix it for me," and then write them a check. As a result, I've been struggling with this thing for days. Oh, well. Just part of the adventure. If I do make this work out, It'll be one of the high points of the whole project.

[Plymouthy Adams]

JOe..glad you making progress..on my Suburban, it had bit hit in the days of yore in teh right rear quarter about the center of the wheel and back..mush have been a pretty hard hit..lots of signs of metal working and lead..anyway..the tailgate and lift gate never lined up..I tried many times to shift that puppy with a porta power only to have it knock the lower edge out of whack...an idea hit me one day to try another method..wha la..it is positioned and Ihave made great headway on it since..that is till the remodel...I never gave up..I just walked away till another day..

[Bingster]

Joe, I agree that if you really did admit defeat you would have stopped. Period! You have what all the great inventors had: determination and perseverance.

I design and build furniture, and one design I had took more skills than I had in my bag of tricks at the time. I had to buy and learn to use a vacuum veneer table, and you should have seen the learning curve on that! It does get discouraging at times, but it's true that taking one step at a time ultimately gets you where you want to go.

I raise my glass to you!!

[Joe Flanagan]

I don't know whether it's age or what, but when I was in my 20s (probably in my 30s, too) I would have hurled that fender across the street into the neighbor's yard and said to heck with it. I would have used different words, of course. I'm not out of the woods with it yet, but I do think I have it beaten. At the end of the last few days, I wound up with the same mess I started out with. It was pretty discouraging. But every day I just tried to take a deep breath and looked at it with a different set of eyes, so I know what you're saying, Tim, about walking away for a bit. Funny that your car got hit back in the days of yore. I thought only pleasant and amusing things happened in the days of yore.

Bingster, now that I've learned more than I ever intended to about metal working, I'll likely never do it again. Interesting to watch how the light goes on eventually. In my case, it was much delayed and not a very bright light at that. Watching John Kelly's videos really helped.

Anyway, this whole experience started off as a quick repair so I could get on to the primer, which is the next step. Quite a detour.

[knuckleharley]

....What's really weird is that I know that the metal is behaving in a certain way but I can't figure out why. There are high spots that won't respond to any tapping. So I increase the force of my blows and then the whole section oil cans. It's almost like there are areas where the thickness of the metal is greater, like it's lumped up in some places.....

That's because some areas have become work-hardened from being hammed on repeatedly,and the surrounding areas haven't. Think of it as metal stress. The fender has the equivalent of a pinched nerve.

Count me in as one of the crowd that things at this point the way to go is to cut it out and weld in a new section because there really isn't any practical way I am aware of that you can get the stresses equalized (for want of a better description) in that fender now. You are like a cat chasing it's tail.

[Joe Flanagan]

Well, I got it. It's almost perfectly flat. I spent hours shrinking and smoothing and I'm at the point where I'm just fine-tuning it. The shrinking process is slow, let me tell you. Granted, the area I was working was very stretched out, but shrinking does work. I actually figured out how to use the torch and not distort the surrounding metal. It's amazing to me that this can even be done, but it works. I'll only wind up using a very small amount of filler. Needless to say, I'm thrilled.