Center cap modification idea

[DriverSideImpact98]

So I have a set of these center caps from a 1990 CV with turbines. And while I was stripping/prepping my stock center caps to repaint (in silver this time), I held them up to my stock (blacked out) aluminum rims, and they fit in the center part perfectly, and look really nice. However, there isn't anything there to hold them on.

Centercaps:



Merc Rims:



I know they were originally held onto the turbines with the little bullet-prong holder things. Can anyone think of any ways to hold them onto the aluminum Merc wheels?

The other thing I was thinking is that they would look cool on my VW van's steelies (with a VW logo/emblem painted or glued in place of the Ford emblem). But there too...there is nothing to hold them on. But it might be easier to figure out a way to attach them to the steel wheels.

As of right now I'm stumped. Maybe this is just some impossible pipe-dream.

[sly]

short of fabbing up an insert that goes in the center of the wheel that will also hold the lip of the centers... no. Even then, I wouldn't expect them to stay in place very well.

[TomO]

If you could find a way to attach the '90 center caps to the newer caps, then you could just snap the newer ones into place on the newer wheels.

Just thinking off the cuff -- maybe you could use a few little clips (or clamp-type things) to hook onto the interior lip of the old cap. Fasten the clips onto the newer cap to clamp or hold the old cap onto the new cap. The clips would be inside the old cap and fastened to the outer surface of the new cap - that way they wouldn't be visible. I envision that the clips would clamp onto the interior lip at the bottom of the old caps to hold it to the new cap. You'd probably want to use at least three clips per cap.

You'd probably have to drill through the newer cap to fasten the clips to it -- that's why I would suggested getting an old, junky cap to experiment with first.

[DriverSideImpact98]

TomO that thought crossed my mind after I posted this... However, the biggest issue there would be getting it perfectly on center. Otherwise I feel it would unbalance things (and might end up flying off). The current newer center cap is just ever so slightly bigger than the 80's cap (a few millimeters on each side).

[TomO]

TomO that thought crossed my mind after I posted this... However, the biggest issue there would be getting it perfectly on center. Otherwise I feel it would unbalance things (and might end up flying off). The current newer center cap is just ever so slightly bigger than the 80's cap (a few millimeters on each side).

Just thinking off the cuff again -- maybe you could center the old cap on the new cap by installing three "alignment studs" on the new cap. The old cap would fit over these alignment studs with a close tolerance fit.

Actually, you could probably use an "acorn nut" on each of the alignment studs with a small spacer underneath each acorn nut. This would essentially give you something similar to the three retaining studs on the OEM turbine wheels for which the old caps were designed.

You would need to determine the correct radius at which to position the studs, then drill the three holes at the same radius and at 120 degree spacing. You might need to experiment a bit to get the correct radius, or maybe you'll get it right the first time.

Then you could pop the old caps onto the acorn nut studs. That would both retain the old cap to the new cap and also center the old cap on the new.

Increasing the size of the acorn nut would allow you to position the hole further toward the center. That way, in view of the fact that the newer cap is not much larger than the older cap, you could use an acorn nut size that would allow you just enough room for the hole.

Also, a suggestion would be to see if plastic acorn nuts are available to minimize weight.

[TomO]

Here's another idea I just thought about:

You take three bolts, three nuts, and three fender washers with holes just big enough for the bolts to fit through (almost no clearance).

You drill three close-tolerance holes in the newer flat cap to fit the bolts (again, almost no clearance).

You locate the holes at 120 degree intervals and on a common bolt circle diameter that is determined as follows:

Each of the fender washers clamps the little inner lip of the older cap to the newer cap and the outer-most point of each washer is up against the inner wall of the older cap when the bolts are tightened down.

What you would do is put a fender washer on each bolt, then put the bolts through the aforementioned holes in the newer flat cap from the outside of the cap, then thread a nut onto each bolt, but leave the nut loose for now.

Then, you take the older cap and put it up to the outside of the newer cap, and then slip each of the three fender washers over the inner lip of the older cap by tilting the nut and washer (the reason for leaving them a bit loose), then carefully tighten each of the nuts, which would clamp the two caps together (you'd probably snug the nuts by hand, then hold the threaded end of the bolt with a pair of vice-grips while you tighten the nut with a wrench). The caps would be centered with each other as long as the holes were located correctly and of a fairly close tolerance with no slop.

You could maybe even put a rubber washer under each fender washer if you're worried about bending the lip of the older cap, or maybe use lock nuts and don't tighten to the point of bending the lip. Or maybe use plastic fender washers that would bend just enough not to damage the lip.

[DriverSideImpact98]

Hmmmm. That has a lot of possibility! I might have to search for an old flat center cap.