Every roadster needs a top at least sometimes. Don't believe me? Take a roadster ride under the oppressive sun or through a chilly rainstorm. Or better yet, experience both ends of the spectrum within the same day and finish it off with the threat of a tornado. I have, and if wanting a top in those cases labels me a coward, then I wear the title with pride. A top is great.
When we say Frank Wallic built...
When we say Frank Wallic built his top, we mean it; he literally cut and bent some strap steel into the shape of a set of stock irons. For the sane among us, consider Superior Car Parts' reproduction irons and bows.
The commercially available top options, however, aren't so great. That's not to knock the tops themselves; they look good and seem well built. The issue is the top-to-car ratio: There just aren't that many top options compared to the number of cars that can wear them. A top is essential to a car's personality, too, so to finish a unique car with a one-size-fits-all top is like mail ordering a wedding cake.
Another solution is to build your own top, but that isn't so great either. A stock-type top can be manipulated into infinite shapes to suit any car but its simple operation belies a complex linkage. One misplaced cut or wayward hole can throw off a top's geometry and make it a binding mess that neither folds as a stock top does nor stows conveniently in the trunk as the aftermarket ones do. And let's face it: when necessary a top may be great, but it's even better if it disappears when it isn't.
Wallic's irons may resemble...
Wallic's irons may resemble stock ones but they're not. He made his main bow base irons 3 inches shorter. He cut the Superior Car Parts wood bow 2-1/2 inches. Later we'll explain why he shortened the wood another 1-1/4 inches.
We've always known Frank Wallic is a craftsman, but his latest project confirms what we've always suspected: he's an engineer too-an eyeball engineer at least. Recently, he modified a set of stock-dimension top irons to fit his car. Among his criteria were that the top had to reflect the car's era and fold as it did by the factory.
What follows is Wallic's elegantly simple way to chop a folding top without impairing its functionality. Typically, we address the individual modifications in the photo captions but in this case we elected to outline them first and use the captions for more specific information. Though the tasks are really quite simple, the reasons behind them require greater explanation.
Top Dynamics
Among the things that distinguish a soft top from a closed-car top is how they behave when chopped. Most closed cars' A- and B-pillars lean toward each other, so clipping them to lower the top they support increases the distance the top must span. Two popular methods prevail: angle the posts further toward each other or stretch the top itself. The latter is definitely the simpler route but neither is very easy.
Cutting the main irons moved...
Cutting the main irons moved the top forward and made the leading side irons hang beyond the corner blocks. Wallic corrected the overhang by trimming the trailing side irons to the proper length.
Folding tops, on the other hand, often suffer the exact opposite problem. The windshield frame and main bow lean the same way: back. Since the rest of the top hinges upon that main bow, clipping its base irons to lower the top actually pushes the whole top forward. Technically it's a problem as the top bow usually leans back at a degree greater than the windshield posts. In those cases, the top, when chopped, moves beyond the windshield. We say it's technically a problem because it's actually a blessing in disguise.
Most people complain that the stock top's backlight (the panel with the rear window) sits too upright when the top is up. While it's purely subjective (some feel vertical elements often look awkward on swoopy things), the other complaint about stock-type tops is objective: when folded down, most top pivots overhang the door opening to make entry and egress even tougher.
Dropping the Top
Wallic clipped 3 inches from the bottom of the main bow's base irons. Due to the main bow's rearward angle, the top came down 2 inches to match the windshield and forward just shy of the same amount. Moving the top forward and down naturally raked the backlight to a more aggressive (and favorable) forward angle. He later trimmed the wooden part of the bow to increase that angle and lower the lid some more, but we'll address that in the captions.
While Wallic bought (and...
While Wallic bought (and used) a set of Superior's top-iron corner block castings, he showed his resourcefulness by making a pair. Though incorrect looking, they're dimensionally exact and a viable option for anyone with the resources.
Chopping the top decreased...
Chopping the top decreased the distance from the door top to the top frame to 13-5/8 inch. Satisfied with that figure and the way the irons paralleled the door top, Wallic drilled the side irons and riveted them to the corner blocks.
Wallic then tested various...
Wallic then tested various halo bow angles by clamping the legs that link them to the leading side irons. Note that the legs must pivot at the stock location on the leading side irons if the top is to fold properly. He shortened the legs that link the leading side irons to the halo bow.