They're different by today's standards and oftentimes different gets interpreted as cool, but cloth roof inserts were anything but desirable when they were common. Their existence was a reminder of the state of technology at the time; deep-draw stamping techniques either didn't exist or weren't economically feasible for most manufacturers until the mid-to-late '30s. Until then, manufacturers made a perimeter roof from several simple panels and filled the opening with wood, chicken wire, burlap, cotton batting, and leatherette. Unless it was for a luxury car, forming a metal panel, welding it in place, and finishing it well enough to look good in paint just didn't make economical sense.
How the tables have turned. Whereas a soft top was once an economic necessity, reproducing one now can cost as much as (or more than) filling the top with steel. The idea isn't new; builders as far back as the '40s filled open tops with roof panels scalped from later model cars.
Colton Hardison starts every...
Colton Hardison starts every job with templates. This cardboard template represents the general shape of the top opening.
But even that mode is relatively obsolete nowadays. A trip to any production bone yard proves that manufacturers long ago departed from the pronounced compound curves that once made top skins perfect transplant material. Yep, even the ugly ducklings of yore were long ago reconfigured as fridges and toaster ovens.
Believe it or not, but the solution to that problem is actually easier-and can be cheaper than finding a donor depending on available resources. Steve's Auto Restorations hammers tin to the ample curves associated with the donor tops of times past. Actually, it does one better: it hammers tin to the exact profile of a roof, making a sure thing out of a job that once required just as much luck as skill.
Steve's offers its roof skins in several forms. First it stocks templates for both popular cars and a few of their less-popular counterparts that crossed the shop's threshold. So if you've got anything from a Deuce to a '36-including the company's own reproduction '33 and '34 bodies and Brookville's Deuce coupe-Steve's has you covered, so to speak.
At this point the panel can...
At this point the panel can go one of two ways: it can be welded to the car or shaped further for bolt-in application. As the panel overlaps the insert channel that must be cut free for the panel to fit, it serves as its own cutting template.
Second, and probably most important to the rest of us who can't afford any three-window, Steve's hammers top skins to match patterns for just about any car. That's right-the shop can actually make skins for a car it's never even seen. It merely needs templates that represent the top's crown and the opening's perimeter.
But we're most intrigued by the third way Steve's offers its skins. The baseline configuration produces a skin roughly an inch larger than the top opening. The finished edge doubles as a template for the end user to trim the top prior to butt-welding the insert in place (for best results the existing insert channel should come out of the car altogether as overlapped panels are invitations for rust). As an option, though, Steve's can flange the insert's edge so the skin drops into place and bolts to the car. That's really slick if you didn't know; by upholstering that panel, a builder can emulate the look of a leatherette top insert yet reliably seal and insulate the car.
Yes, the times are a changing but no it's not always for the worse. In fact, you could say it's for the better: old cars can still look old without feeling so fragile ... or drafty for that matter. And the best part is, these pre-formed panels take the gamble out of an already-involved procedure.
He cuts his templates a specific...
He cuts his templates a specific amount larger than the insert hole. In this case he extends the template 7/8-inch larger than necessary.
The second and third templates...
The second and third templates indicate the roof's profile. This one plots the horizontal plane for all '33 and '34 Fords but other templates fit specific body styles (three- and five-window coupes, sedans, and so on).
After cutting a sheet to match...
After cutting a sheet to match the cardboard template, Hardison shapes it on a Yoder power hammer. Though entirely possible on an English wheel, the hammer is considerably faster and makes the job a one-person operation.
To make the insert a bolt-in...
To make the insert a bolt-in job, Hardison must transfer the top-insert channel's actual dimensions. The only problem is that the opening isn't visible. Remember, the panel overlaps it by 7/8 inch, so he made this scribing tool.
The tool's lower lip and hardened...
The tool's lower lip and hardened scribing tip are on the same plane, so the tool will scribe a line wherever the lip meets an edge. Here it is at the edge of a '33-34 Ford insert channel.
Hardison had to cut the panel...
Hardison had to cut the panel larger than the opening to account for the lip dimension, the bend radius, and the panel clearance gap. Trials with strips indicated that he had to extend the cut line 0.20 beyond the opening to form a panel with a 1/2-inch lip that cleared the opening by 1/8 inch for upholstery material or beading.
Steve's Auto Restorations...
Steve's Auto Restorations uses a '40s-vintage ERCO former/flanger to create perfectly crisp edges. We really don't need to show it as probably nobody reading this has one, however, it's one of the things that makes the shop's inserts so nice.
With the scriber in place...
With the scriber in place and its lip against the channel, the tip can be pressed against the top insert and dragged around the top opening. As long as the tool's throat extends a hair beyond the insert's overlap, it will transfer the channel's dimensions perfectly. In case you were wondering how to establish the shape of the cardboard template, here's an option. Just remember to extend the cut line by the necessary amount to make the template sufficiently larger than the opening.
Hardison showed a very affordable...
Hardison showed a very affordable and effective alternative to the ERCO. He scribed a line 1/2-inch inboard of a panel's edge and bent along that line with an adjustable wrench. Remember to adjust the jaws loose enough so they don't bind on the bent flange and remember to bend in increments 15 degrees or less with each pass.
On the other hand, Hardison...
On the other hand, Hardison says that flanges 3/8 inch or shorter more readily shrink as they're formed, so he trimmed the flanges in the radii.
Just because the shorter flange...
Just because the shorter flange shrinks easier doesn't mean that it shrinks enough to prevent the panel from cupping. Hardison eliminated the last bit of distortion by lightly tapping each flange's edge down until the panel laid flat.
Almost any flange bent along...
Almost any flange bent along a radius can wreak havoc. Outside radii are the worst offenders as the metal in the flange gathers yet flattening the gather causes the panel to cup. Shrinking the edge works well but it's an incredible amount of work.
Rather than finishing the...
Rather than finishing the edges in the radii with the wrench, Hardison tapped them to shape against a dolly. If done properly, off-dolly hammering can shrink metal gathered in outside radii. Conversely, on-dolly hammering can stretch flanges in inside radii.
The slight give in the cardboard...
The slight give in the cardboard atop Hardison's table let the panel deflect enough to bend, but not enough to kink the panel. Note how the flange at the corner is shorter than the flange through the rest of the panel.
Fastening the panel seems...
Fastening the panel seems tricky but Hardison addressed it with an elegantly simple solution. He sheared sheet into 1-inch square tabs and bent them 90 degrees.
The insert's placement during...
The insert's placement during dictates the panel's fit, so Hardison spent some time nudging it into place and checking the gap consistency.
Hardison welds the tabs flat...
Hardison welds the tabs flat side down to the edge of the flange. The tabs land where the flange does: at the channel's floor as this one does. After Hardison welded the tabs to the flange he marked their location on the inside of the filler panel.
Satisfied with the fit, he...
Satisfied with the fit, he drilled through the top insert channel and the tabs that he welded to the inside of the filler panel. Note the reference marks he drew two steps earlier.
Finally, he fastened the panel...
Finally, he fastened the panel to the roof with self-tapping sheetmetal screws. The panel is flat enough to take paint with some further prep but it could just as easily be padded and upholstered to look like a top insert. Unlike a padded top, though, it will last and, if sealed properly, never leak.