No pattern, No problem!! UPDATE

[Randy Ferguson]

Metalshaping/Panel replacement '34 Chrysler fender



There seems to be a growing interest in panel replacement and metalshaping in general. I worked on a '34 Chrysler front fender Saturday and thought I might post a bit of a tutorial on how I make and install panels.
The first picture is how the fender looked when I received it. Due to possible light collision, rust and botched previous repairs, it was time for some new material.




The owner happens to have an original car identical to this one, which is being street rodded. This area of the fender has to be perfect, as the fender irons and frame horns sandwich the fender. Both front fenders were bad, so we were forced to use the original cars fenders as the patterns. The owner removed the front bumper and made me a plaster of paris mold off the original fender. I then use 1/4" hot roll rod, bent to conform closely to the surface of the mold. I then use a heavy paste furniture wax to insure that the buck will release upon completion.
Once I have the rods placed where I want them, I use 1/4" nuts to hold it off the surface of the mold. (The same can be done off the inside of an original part) I use fiberglass reinforced bondo to cover the rods and to achieve the true surface by making sure the filler has good surface contact where I need it. The voids left between the rods are to see how the metal sits on the buck. The area where you see the regular bondo is in an area that I thought may need to be hammerformed, but as it turns out, that was not necessary.



I failed to get a picture of the new panel resting on the buck, but here it is tack into place. I use a MIG welder to tack the two together. Note that this is butt welded, not lapped!



I then go in and weld a continuous bead between each spot weld, in 1" increments. If it looks like the panel is getting out of control due to warpage, I'll grind down the proud weld and crush it with a hammer and dolly. This will stretch the metal that has been shrunk from the welding process. You do not want to work outside of the heat affected zone, This is the blued area around the weld bead. Anything beyond the heat affected zone is not in need of further work. As the metal is stretched in the HAZ, it will relax and the distortion will disappear.



Once I have the welding done, I use a 1/16" disc in a cut-off saw to remove the proud weld, leaving it just above the surface by a few thousandths. I then crush the welds, relieving the shrinkage from the heat of the welding process. This also cold forges the weld seam, making for a stronger joint. If done properly, it will be as one piece of metal with no trace of being welded.
Once I'm satisfied with the results from the hammer and dolly treatment, I will further planish the panel using a slapper and dolly. The slapper has a much larger contact point, yielding a smoother, straighter finish. Any high areas of weld can now be taken care of and if it feels and looks straight, the shrinking disc can be run over the panel to further smooth out any slight imperfections. The slapper and shrinking disc are both in this shot. The slapper is one I made from an old car leaf spring, and the shrinking disc is a 9" diameter piece of 18ga. stainlees steel sheet with a 1/4" flange. It runs on a 6,000 rpm grinder and produces plenty of heat to controllably shrink sheet metal. The shrinking disc is available from John Kelly at ghiafab@msn.com



And, here's another shot of the near completed panel. I have yet to roll in the wire edge, but the bulk of the work is complete. This is one tough panel to shape. There isn't a straight part of it and much of it is what we refer to as reverse curves.



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Hi Folks,
I posted a tutorial a few days ago on how to fabricate and install body replacement panels on a '34 Chrysler fender. In that post, I mentioned that the damage was so bad that I was not able to get enough information to make the part, but that the owner had an original car that was usable to make a plaster of paris mold to give me the surface information needed to make the part. This mold was taken off the right fender. When I spoke with the owner about doing this, I told him one side would suffice. So what to do now??? The left fender needs the same treatment, but I have no pattern for it!!!
Barry Kives asked me a while back if a pattern could made off an existing part, without damaging the paint. Although this one isn't painted, the process it the same. Tonight, I will show how to make a pattern off an existing shape. If you were to be involved in an accident, in which a body panel was so badly damaged it was beyond repair, and no parts were available, you might find this of interest. By having the mold from the right fender, transfering that to a wireform/bondo buck and making the part, I now have the information needed to make the panel for the left fender. This will probably be a two part post, as I haven't finished the panel yet, but plan to this week-end.
The right fender has the panel installed and has been metalfinished, meaning that there is no need for body filler. 2-3 coats of primer will take care of any minor imperfections. This will allow me to make a flexible shape pattern from it.
To make the pattern, start by laying strips of 1"-2" medium tack transfer tape on the area needing copied. (The transfer tape can be purchased from your local vinyl sign shop.) If you lay each succesive strip overlapping the previous one, it will make it easier to pull off of the panel. You want to make sure the tape lays down tight against the surface, or it will not be a good pattern. Any loose areas in the tape, will defect the quality of the part.




Fiberglass reinforced strapping tape is then used to hold the transfer tape together and to add strength to the pattern. In most cases, 1 layer over the top of the transfer tape will provide you with good results, especially for 1 time usage. I run the strapping tape at a different angle as the transfer tape to tie it all together, then run a single strip of strapping tape around the perimeter for added strength.




A Sharpie can be used to mark the perimeter of the panel to give you a better idea of where the true edges are. Transfering the edge cutlines onto the metal will help to align the pattern in the same spot each time. It is very important that the pattern be indexed to the metal to insure it is fitted at the same exact spot each time it's layed on the metal, otherwise, you will fight it the whole way.
Here is the flexible shape pattern, flipped inside out for use as the pattern for the left fender. Along with it, is the blank of metal, cut about 1" oversize all around to insure there is enough to trim off later. Laying the flexible shape pattern on the flat piece of metal tells where the metal needs stetched, or shrunk. I chose to make this one by stretching only. Normally I would try to split it close to 50/50 stretch and shrink, but this panel isn't so extreme that I can't get by with it. It won't thin out very much at the thinnest point. By the way, I'm using 19ga. commercial quality cold rolled steel. Nothing fancy! All the marks on the blank is used as a guide to tell me where to stretch. The flexible shape pattern tells exactly were the panel needs stretched. Any areas on the pattern that doesn't lay down tight against the metal, is an area that needs to be stretched.



This is after about 5 minutes of hammering on the beater bag. The flexible shape pattern tells me that it's very close, with just a couple small areas that still fit loose to the panel. It will need run through the english wheel to planish the lumps and bumps and to further refine the shape.



After running it through the english wheel and smoothing it all out, the shape pattern tells me that there are still some small areas left to be stretched. I can lightly tap these areas by taking it back to the beater bag and just giving it a few love taps, or I can crank up the pressure on the e-wheel and do it that way. No bigger than this panel is, I chose to do it in the wheel. Just a few minutes and the shape pattern was fitting tight all over, which tells me the panel now has the right amount of surface area in the correct spot. Although, the panel looks way off, it's only an arrangement (form) issue. I can bend it around by hand now in to any arrangement I want and not change the surface area (shape)
Just a little manipulation and it'll fit great!! I'll make some contour gauges off the other fender to use as a guide for re-arranging it into the desired form. That will be in the next installment though.

I think I made this panel, and this post, in about the same amount of time!! 2 hours



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Hello All,
Well, I'm sure you're all sick of looking at this stuff by now, so I'll wrap it up in this post. I thought I had done a better job of taking pictures, but somehow I missed a lot of what I should have gotten. I skipped all the installation sequences on the left fender, as it was just a repeat of the right one. Unfortunately, I didn't get the re-arranging of the panel with the contour gauges either, so please forgive me!!
The grill shell was badly damaged from a collision apparently. It had been repaired previously, but not too well. There was a tear in the metal about 5" long, that had been gas welded, which the weldor did a good job of welding, but the metalfinishing was not so good! The metal surrounding the weld was stretched beyond belief and the entire grill shell was twisted, more than likely from more stetching on one side than the other. More material on one side of a panel will almost always result in a twisted condition. The only way to effectively repair it is to get rid of the residual stretch. In this case, although the metal was in fairly bad condition, having been beat on severely and fatigued from all the stress, it was still not beyond repair. Making a new piece was an option, but not necessary.
I started the repair by first transfering the outline of the fender, where it mounts to the grill shell onto a piece of poster board, indexing where the mounting holes were and any other information I could gather. I then used this as a template to guide the first step of the repair, which was to make sure the grill shell and fenders would mate up properly. One side was fair, but the other was horrible!! A little shrinker/stretcher work along the flange had this issue resolved in no time, but now comes the fun part....trying to get rid of all that extra material from the someone beating the heck outta this thing. The trusty shrinking disc was the tool of choice. I failed to get pictures of this process, but for the amount of stretched metal to deal with, it was a lengthy process. Some slapper and dolly work was necessary to remove the dents and dings before going at it with the shrinking disc, but those worked out pretty quick.

Here is the twisted mess



I wish I would have gotten more pictures of the progress, but I was short on time and failed to do so. If you run a search on this site for shrinking disc, you should find another post on the process I use when running the shrinking disc.

After several passes over this with the disc and lots of persuasion, it finally came around to my way of thinking. Remember, metal is stupid!! You tell it where to go, it'll obey!! Sometimes it'll try to fight back, but you just have to tell it who's boss!!

Here are all the finished parts

[Dick Bear]

Hey!

Thanks Randy for the complete process in one post. I will keep it in my personal reference guide to successful methods.

Dick Bear

[Bob Baisden]

Randy,

Looks great! How did you add the accent line at the edge?

thanks
Bob

[Boogiemanz1]

Great job Randy! Going the extra mile to metal finish it makes it more than a repair. Soon, with work like that you will have folks lined up just waiting to get in.............john

[John Kelly]

Hi Randy,

You are doing some beautiful work!

John www.ghiaspecialties.com

[Pedalcar]

Hi Randy,

The talent shows.


Ben

[Steve Hamilton]

Hi Randy

Yes I do remember you at MM number one ( the energizer bunny comes to mind) lots of questiond and lots of energy!!!!!!

You have come a long way in that time frame from a novice to an advanced metal shaper!!!!!!!

As many have already stated if there is the desire to learn ask questions, and get out to the shop and put in the required time, and sure enough the talent will develop.

Randy is a prime example of what can be accomplished !!!!!

Excellant job on the fender and the start of your story !!!!!

I have learned a great deal from this and other forums but I learned much more from the hands on in the shop and at the international METAL MEET!!!

Steve Hamilton

[Randy Ferguson]

Hi guys,
Thanks for the compliments.

I thought I had posted this last night, but I was falling asleep at the computer and must have failed to hit the submit button, but anyway, to answer Bob's question, I used my bead roller. I rarely use it and I doubt I would ever use the dies I modified, so nothing is lost really. I had Ryan, my 12 year old son, turn the crank while I held a grinder against the die to 'machine' it to the desired shape. Only one die had to be modified, the mate to it is left untouched.



The wireform had the information I needed to transfer to the metal for this joggle, bead, whatever. Once I had it layed out on the panel, I simply rolled it through the bead roller, decreasing the pressure on the dies as it moved along. It didn't turn out perfect, but after a couple minutes of slapper and dolly work it was in fine shape. To blend it in to the smooth area, I used the shrinking disc and lightly run over the tapered edge and it smoothed right out.

Trial and Error mostly, Bob, 'cept this time it was kind of a successful error!

[Kerry Pinkerton]

Nice, NICE work Randy!

[jlrussell4]

Hi Randy,

VERY nice. Thanks for sharing, I learn something new everytime you post.

Jim

EDIT: Randy, I just checked out your latest posts to the gallery. Great tutorial It didn't even need text.