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Someone said something about free metalshaping lessons a few weeks ago.............Better late than never, huh!!!
I hope to write several tutorials on the rebuild of this '40 Willys coupe.
I was contacted by the owner to build this one, after another gentleman had started on it, deciding it was more than he was willing or able to handle.
In speaking with him, he convinced me that there is a need for '37-'42 Willys replacement panels, so he has agreed to give me extra time for the build to allow me the needed time to build patterns, bucks and forms for offering a complete line of replacement panels for these coupes.
In this tutorial, we'll be dealing with the issues of replacing obsolete sheetmetal in an area with lots of detail.
The original roof sustained a hard hit sometime in it's past and was previously 'repaired' with about a 3/4" thickness of lead.
This area is impossible to get to from the backside, so repairing it is a near impossibility.
The heat of all the previous work and tons of hammering from the inside of the roof panel with a pick hammer had eliminated any chance of saving this one. The metal was ground so thin that it literally had holes ground through it in several spots where the pick hammer had been used. If you look closely in the photo, you can see a couple of the holes and also notice the thickness of the lead. I melted a section of it out so it would be apparent how thick it is. There is supposed to be a reverse curve in this area, but due to the severity of the damage, it was just filled completely with lead.
The damage runs from about two inches below the top of the windshield, across the entire top of the door and down to the beltline, including most of the sail panel, which is where the holes are left from heavy grinding.
In order to make a new panel for this section, I had to rely on the information from the right side of the roof to provide usable patterns for the damaged left side. In order to gather this information, a flexible shape pattern was made, comprised of sign makers transfer tape and reinforced strapping/shipping tape.
This is the best method available for copying existing shapes, as all pertinent information is captured, and it can be used as a road map to guide in the shaping of the new panel.
In addition to the shape pattern, I also indexed it, and made corresponding contour gages to make sure the final arrangement is correct. These will not be used until the flexible shape pattern fits tightly to the new panel, insuring that the proper amount of stretch and shrink has been introduced properly. If the shape patterns has areas that fit either tight or loose, this tells us that there are areas that still need to be stretched or shrunk. Properly indexing the shape pattern will insure that it's placed on the panel in the exact same location each time it's checked for fit. Areas in the shape pattern that are fitting loose, tells us that the metal needs to be stretched to fill this void, whereas areas that are tight, is an indication that there is to much material present in that particular area and it either needs to be shrunk, or the area around it is needing stretched. It's always best to slowly bring up the low spots (loose areas in the pattern) rather than resorting to shrinking high spots. This a slow, meticulous process, but the results are amazing!
Once the flexible shape pattern is fitting the panel, the contour gages are used to make sure it is in the proper arrangement (form)
Without a buck to clamp the panel to, this is all we have to go by to get the final arrangement correct. It will take some manipulation by hand to get this final arrangement, but the panel will want to go, simply because the proper amounts of stretch and shrink has been placed in the proper areas.
This part of sheet metal shaping take some experience to understand, but once it's learned, it makes duplicating panels much easier than any other method, short of building a buck.
I'll add photos of the contour gages later, as I failed to get a picture of them.
I made the decision to make this panel in two pieces. I split it in an area that requires the least amount of shaping. This not only makes it easier and faster to shape, but also maintains maximum thickness of the material, which in this case is 19ga. cold rolled steel.
Here, the panels are shaped and ready to be welded.
And here is a shot after welding and planishing the weld seam.
It's obvious that the edges need trimmed and the flanges tipped, but the initial shape is there and now we can focus on tipping the edges to form the flanges for the door jamb and windshield opening.
Creating the joggle to conform to the top edge of the door is a painstaking process, but one that has to be done, so you just have to be very patient and get it right in order to look good.
Here a few shots of the new roof section ready to be welded in.
I'll be installing this panel next week, and will add more then.
Randy Ferguson
Ferguson Coachbuilding
Robinson, IL
(618) 544-2972
[email protected]
www.metalmeet.com
I hope to write several tutorials on the rebuild of this '40 Willys coupe.
I was contacted by the owner to build this one, after another gentleman had started on it, deciding it was more than he was willing or able to handle.
In speaking with him, he convinced me that there is a need for '37-'42 Willys replacement panels, so he has agreed to give me extra time for the build to allow me the needed time to build patterns, bucks and forms for offering a complete line of replacement panels for these coupes.
In this tutorial, we'll be dealing with the issues of replacing obsolete sheetmetal in an area with lots of detail.
The original roof sustained a hard hit sometime in it's past and was previously 'repaired' with about a 3/4" thickness of lead.
This area is impossible to get to from the backside, so repairing it is a near impossibility.
The heat of all the previous work and tons of hammering from the inside of the roof panel with a pick hammer had eliminated any chance of saving this one. The metal was ground so thin that it literally had holes ground through it in several spots where the pick hammer had been used. If you look closely in the photo, you can see a couple of the holes and also notice the thickness of the lead. I melted a section of it out so it would be apparent how thick it is. There is supposed to be a reverse curve in this area, but due to the severity of the damage, it was just filled completely with lead.

The damage runs from about two inches below the top of the windshield, across the entire top of the door and down to the beltline, including most of the sail panel, which is where the holes are left from heavy grinding.

In order to make a new panel for this section, I had to rely on the information from the right side of the roof to provide usable patterns for the damaged left side. In order to gather this information, a flexible shape pattern was made, comprised of sign makers transfer tape and reinforced strapping/shipping tape.

This is the best method available for copying existing shapes, as all pertinent information is captured, and it can be used as a road map to guide in the shaping of the new panel.
In addition to the shape pattern, I also indexed it, and made corresponding contour gages to make sure the final arrangement is correct. These will not be used until the flexible shape pattern fits tightly to the new panel, insuring that the proper amount of stretch and shrink has been introduced properly. If the shape patterns has areas that fit either tight or loose, this tells us that there are areas that still need to be stretched or shrunk. Properly indexing the shape pattern will insure that it's placed on the panel in the exact same location each time it's checked for fit. Areas in the shape pattern that are fitting loose, tells us that the metal needs to be stretched to fill this void, whereas areas that are tight, is an indication that there is to much material present in that particular area and it either needs to be shrunk, or the area around it is needing stretched. It's always best to slowly bring up the low spots (loose areas in the pattern) rather than resorting to shrinking high spots. This a slow, meticulous process, but the results are amazing!
Once the flexible shape pattern is fitting the panel, the contour gages are used to make sure it is in the proper arrangement (form)
Without a buck to clamp the panel to, this is all we have to go by to get the final arrangement correct. It will take some manipulation by hand to get this final arrangement, but the panel will want to go, simply because the proper amounts of stretch and shrink has been placed in the proper areas.
This part of sheet metal shaping take some experience to understand, but once it's learned, it makes duplicating panels much easier than any other method, short of building a buck.
I'll add photos of the contour gages later, as I failed to get a picture of them.
I made the decision to make this panel in two pieces. I split it in an area that requires the least amount of shaping. This not only makes it easier and faster to shape, but also maintains maximum thickness of the material, which in this case is 19ga. cold rolled steel.
Here, the panels are shaped and ready to be welded.

And here is a shot after welding and planishing the weld seam.

It's obvious that the edges need trimmed and the flanges tipped, but the initial shape is there and now we can focus on tipping the edges to form the flanges for the door jamb and windshield opening.
Creating the joggle to conform to the top edge of the door is a painstaking process, but one that has to be done, so you just have to be very patient and get it right in order to look good.
Here a few shots of the new roof section ready to be welded in.




I'll be installing this panel next week, and will add more then.
Randy Ferguson
Ferguson Coachbuilding
Robinson, IL
(618) 544-2972
[email protected]
www.metalmeet.com