So I've not had very good luck finding the product I *really* want for my spherical bearing conversion.
I had envisioned using a sealed spherical bearing or through bolt ball joint or pillow ball or whatever people call them in a housing and with a pair of spacers which would allow the combo to be used in the '84-'87 front and rear control arms, as well as the '88 front control arms.
I had also thought about using small needle bearings in the '84-'87 rear and '88 front, because those pivots were co-axial and didn't need any angularity. I decided to pursue using spherical bearings everywhere because it wasn't a good application for needles and because I wanted the elegant design bragging rights of being able to use the same parts for everything.
So I've solved the problem of using the same parts for everything. I have a design that will work. However, I don't have a spherical bearing that will work.
In other news, I had been thinking about hard pivots for BMW semi-trailing arms. These bushings are very small in diameter, which is good for a rubber bushing. However, it's not so good for using spherical bearings or ball joint.
There are "plain linear bearings" which could do the job just fine AS LONG AS the control arm pivots are coaxial.
Per BMW, the OD of the E30 trailing arm bushings is 30mm, and those bushings mount on 12mm bolts... so whatever I can use in the E30, I can also use in the Fiero applications.
http://www.realoem.com/bmw/showparts.do ... g=33&fg=30
So over the weekend I realized that I just need to use the plain linear bearings in the early rear and 88 front and find the right spherical bearing for the early front later.
So on to McMaster:
Common sizes for "Fixed alignment linear sleeve bearings" have 1 1/8 OD and run on 5/8" shafts.
Of the available liner and shell materials, PTFE liner with fiberglass shell and ceramic liner with aluminum shell both have load capacities of 4691 lbs in the size that interests me. The PTFE liner has a max PV of 30,000 and the ceramic liner has a max PV of 40,000 but "requires a thin film of lubrication". I'm not sure exactly what that means from the implementation perspective.
At 1 1/2" long, they have a lot more bearing area than a spherical bearing.
Those part numbers are 6673k14 and 8356K13
Both types require 8-16 RA surface finish on the shaft, so I'll have to use precision ground rod and drill it--NOT fun since precision ground rod is typically hardened in the neighborhood of Rockwell C60--for the 12mm through bolts.
McMaster does list "tubular shafts" with precision ground exterior at 9 RA and Rockwell C58, but the smallest OD they show is 3/4". I guess I could call and ask if they can get 5/8 OD.
Also, 12mm clearance (31/64") and 5/8" OD leave a 0.070" wall thickness. This is pretty thin to be clamped to the mounting ears for the bushings with 12mm bolts pulled hard (80 ftlbs?). I'd like to spread that load out a bit.
Hmm... 31/64 drill bushings with heads have 3/4" OD, so they're too large.
However, the 8492A243 drill bushing has 5/8" diameter, 3/4" depth with a 7/16" hole that could be drilled (with carbide!) out to 31/64. The length tolerance is +/-.010, so I'll have to look up what the length tolerance on the linear bearings is...