A picture of the Hilborn streamliner shows four evenly spaced fasteners around the outside. I don't see any way to drill and tap a wheel without hitting "air". So how do the screw on Moon disks work? Edsel's custom speedster had some slick looking covers as well. No trim ring and no visible fasteners. Could they just be held on by the center cap? I think there's a Deuce RPU out there that has some accessory covers too but they look too much like a wide five cap to me. Fabbing a cap that snaps on like a trim ring might be a little beyond my skills. Any ideas?
If they are attached really far out, they could be screwed into the bead area and not leak air. Kinda like the screws into the bead of a drag slick to keep it from rotating. If the fastners are farther inboard, maybe they welded a tab inboard of the rim to attach to. I have seen this done with dzus fastners at B'Ville TZ
I have a set of 1930's accessory covers for 16" wire wheels. The center hole is captured by the stock hubcap; the back has several, probably four, loops with springs (about like a stout throttle return spring) that hook onto the spokes; the outer rim is captured by the trim ring. They would pretty certainly stay aboard without the trim ring. I think that if you wanted to make something like this, spinning would be the technology to investigate. Moons were made this way, and I suspect their heritage probably involved the spun wire wheel covers on 1930's airplanes with exposed landing gear.
Spinning is absolutely what I had in mind. I'm trying to eliminate the trim ring all together if I can. I just really like the look of the covers on the Hilborn car and Edsel speedster. The springs are a great idea - I remember you mentioning it before now. Suppose I could also replace the springs with thick wire hooks that have an allthread coupler welded to the "disk" end. Four countersunk flathead bolts wouldn't clutter the smooth cover too much. Dzus fasteners might look too new for my car? Thanks for the ideas. But to clarify, You can definitely drill through the outer edge of a rim with no problem? These are bias plys on '35 wires if that makes a difference.
Spun aluminum discs, "MOON" discs, come with short screws that barely poke through the rim. When you drill be sure to use a stop collar on the bit if you do it with the tire on. Four small holes in the wheel lip wont hurt anything and the bead is a good half inch thick on most tires. As mentioned above, drag cars have been screwing the tires to the rims for years to keep them from slipping on the rim.
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