I'm looking for some help in making patch panels fit. Reading the threads on body repair on the HAMB really makes me wonder how they cut a crazy rusted out piece and then we see a panel cut and fit to perfection without so much as a small gap. What's the best way to go about getting the panel to match the cut out ?? I could sure use some help... Thanks
I'm no pro at it but cutting the rust out and make a poster board pattern, trace it on sheet metal, cut it out and weld it in, it's basically a simple process. You do need to decide whether your going to butt weld or (overlap , not the recommended way) HRP
There are a few different techniques you can use to get a perfect fit. The most accurate way I have found is to trim the patch so it overlaps the original metal by about 3/4". Hold the patch in place with clecos or sheetmetal screws. Then cut along the edge of the patch with an airsaw. The edge of the patch acts as a guide so you get a nice straight cut and the airsaw blade is thinner then a conventional cut off wheel so you get a nice tight gap for butt welding. The quick and dirty method that I normally use is to cut out the rusted metal to the exact size I want the patch to be on the first try. I then clamp this on top of my patch panel and trace it out using a scribe ( a scribed line is more accurate than a line drawn with a marker). Then I cut the patch out using a zip disc on a grinder. With a little fine tuning I end up with a perfect fitting panel. This method takes more practice as you must compensate for how much material is removed by the thicker zip disc, but I find it's faster then method 1. Sent from my SM-G950W using The H.A.M.B. mobile app
no pro here either ! . I overlap the patch, get it right, tack it inside and out, make a slot with the wizzer where they overlap, slip my sabersaw with a metal cutting blade into the slot and cut as far as I can, wizzer the rest... this cuts both at the same time, grind the tacks off, fit the skin and patch with your panel clamps, make a tack close to both sides of the clamps, move the clamps and repeat, grind here, and there, as too much in one place creates enough heat to worp the panel... . the 90* ends of the door patches are not always right, I cut them off, trim them to match the inner skin and the door's taper, cut strips that I clamp on the inside of the inner skin, after welding the outer edges of all 3 I grind the high spots then I use a belt sander to get it right, if you sand all around the welds the strips you welded in look like the stamped over stock skins...
Make perfect pattens Fit the panel Scribe a cut line Trim with aviation shears. Never use the yellow handled ones File the cut line straight
Basically, take your time and make the patch fit perfectly. It's easy to remove metal......much more difficult to add it.
Sneak up on it. Remove most of the rusted stuff, then lay the patch in place with a little overlap. Scribe the cut line EXACTLY with a sharp point, then cut RIGHT ON THAT LINE with sharp tin snips. Sometimes I find it easier to cut the sheetmetal accurately if the strip is narrow, so I cut it down to about a quarter inch wide with a sloppy cut, then I can do the last one right on the line. Use a cut off wheel for the spots you can't access with the tin snips. Every guy doing body work needs a good sharp set of tin snips. You need lefts, rights, and straights. I've found WISS brand at my local Menards or Lowes, and they are pretty good. When they are dull paint them with an obnoxious color and only use them to cut the dull edge off your grinder disk.
Here is the system I came up with on my own. I've never seen it addressed anywhere. I make the patch panel with small tabs spaced a few inches apart. Each has a hole for a Cleco. I offset the tabs in a bead roller with step dies. Scribe the parting line as mentioned above. Put a score mark at the base of each tab to make them easy to break off. Cleco the sides together. Tack weld. Break off the tabs. Trim as needed with a Dremel tool with a thin cut-off wheel. Finish weld.
I made patches and the Model A door was the one I did twice. I have some pictures in my rebuild thread. No pictures on this phone, sorry. Cliff Ramsdell
I worked a few years in Ford's Body Engineering Department. One thing to remember: No panel on a car body is completely flat. And most have compound curves. If you can induce some curvature into your patch panels - either by an English wheel, pounding on it, or any other preferred method - you will save yourself gallons of Bondo down the road.
I make a masking paper pattern, transfer to 20 ga, cut, bend, shrink, fit until I’m happy with how it fits, trim as needed, cut out the offending panel, weld the new one in. Easy on low crowned panels like this ‘65 Ford wagon. Very little filler will be needed. Sent from my iPhone using The H.A.M.B. mobile app
I do So much easier to hammer and dolly This wheelhouse is butt welded in the center of its style line The lower qtr patch is butt welded about 4 inches above the lower style line Makes hammer and dolly/finish work so much easier Fit, scribe, cut, file, weld It takes time but pays off on welding and finishing
This is the way I do it. I fit with clecos, get it as close to perfect fit up as I can then change those clecos out to aluminum rivets every coulple inches or so and cut it. The rivets hold the panels better for air sawing and aluminum rivets drill out easy! I tack as I cut after drilling the rivets,
Instead of a cut off wheel I sometimes use a grinder with a flap disc in it. It removes small amounts at a time and I can really fine tune the patch to get it close. Then I sometimes use magnets to hold the patch in place while I tack it.
You can make your own sheet metal clamps. https://www.jalopyjournal.com/forum/threads/tools-sheetmetal-clamps-for-holding-patch-panels.11673/
You can sharpen snips, but only work on the edge that cuts. Do not file or grind where they slide against each other, and do not cut grinding discs with them unless you have dedicated ones for doing so. Used to drive me crazy when another bodyman would grab mine to trim a disc.
Great Work! Stupid question but when you butt weld in the center of the style line, how do you keep from flattening it when you grind the weld?
here's a little fix I did with my $20.00 yard sale sheet metal brake and a shrinker/stretcher from Eastwood.
looking at the picture above I can see that I bent the piece to cover the rust then cut the body to fit the piece since the piece was easy to make square.
I grind just the weld. I shaped a piece of metal with the curvature of the style line This keeps it shaped correctly during the hammer process
What little I've done I butt weld it. Naturally tack and skip tack and skip. Vertical welds I like to tack and cool and then....weld it "down-hill" Welds very fast and less warping. I had a "supposed" body guy tell me he liked to cut the patch a little larger than the hole....put the patch inside the hole using panel adhesive! With just the thickness of the metal difference...fill and smooth with body filler! Never tried it but sure sounds convincing. 6sally6
Seen that done many times Some repairs probably deserve the glue in method I refuse to do that because that method never improves your skill level
How to make patch panels with a ball peen hammer and a tree stump. Before you laugh check out the results he gets with some primitive tools. Body work part starts 25 minutes and 43 seconds in.
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