I have these knuckles pictured above with an aluminum bore of 1.52x that need to have sphericals in them instead of bushings.
I can find the 1.5OD com12 bearings to loose fit in the bore but I need to keep them centered so they don't slide forward/backward under load. So... I figured I'd make some aluminum "cups" that have a snug 1.515 OD, a slightly larger flange that rests to set the depth and then have them be captive in the control arm. BUT, the control arm's "mouth" width will be set by the misalignment sleeves with enough clearing to allow for toe adjustment. I see an opportunity for that to allow play.
Plan B was to use a smaller COM-8 with a 1.000 diameter, 0.500 bore and then sleeve the entire length with a hard stop one way and a snap ring groove the other. This seems surefire... except I've never cut a snap ring groove... and is a 1/2 diam grade 10 bolt enough for the stress of a lower control arm in double sheer?
Any advice on how to do this properly is much appreciated.
1.500 OD bearings sitting in a 1.515 cup? If I understand it correctly, you're looking at a .0075 wall thickness.
I would think a 1/2 inch diameter bolt would stand up to your tensile and shear requirements.
Dan
http://www.tessco.com/yts/customerservice/techsupport/whitepapers/pdf/bolt_grade.pdf
In reply to 914Driver:
No... the cups would be sandwiching it in-between them, with the bearing using the knuckle bore as it's seat in the case of the 1.500 OD bearing.
The sleeve to use a smaller 1.438 OD COM-12 would be ~.087 and I could turn it from 1.5x.120 wall roll cage tube. I'm not sure if that is enough for a snap ring groove or what tool to use to do that (I can picture it in my head... I just don't have one in the box under my lathe or know what it is called).
When I install a bearing like this: I've done LCA inner mounts and upper strut mounts to allow adjustable camber, I instead multi-step bore the sleeve. The smallest ID is a shoulder for the bearing to be seated on and the middle bore is for the bearing it's self and the larger bore is the installed OD of the snap ring. I then install the bearing, then the snap ring, and then a second sleeve with an ID of the bearing and a ever so slightly larger OD of the step bore. I press the second sleeve in to the main sleeve and then weld the two sleeves together at the edge of the two sleeves. I now have a snap ring grove that is an exact fit! IF I had the correct tooling to make a grove I would but the cost for me is just to high. I've tried to grind a cutting bit but doing that by hand is just to difficult.
In reply to jimbbski:
Jim: Any reason the bearing can't sit in an aluminum sleeve vs steel?
Whatcha got there? T-bird?
sobe_death wrote:
Whatcha got there? T-bird?
Lincoln actually but, yeah, same part.
Giant Purple Snorklewacker wrote:
In reply to jimbbski:
Jim: Any reason the bearing can't sit in an aluminum sleeve vs steel?
Steel, aluminum I see no difference. I would prefer steel, even when installed into an aluminum part. That is as long as the opening in the aluminum part is bored straight. That is machined and not just precision cast. If not machined then I would use the same metal for the sleeve as the part so I could add some welds to the edges of the sleeve to retain the sleeve in the part.
The aftermarket spherical bearings I have seen run a 2 piece arrangement, There is an outer sleeve that is machined to light-press-fit into the carrier, retained with a step on one side and an external snap ring on the other. Then a standard spherical bearing is pressed into that sleeve and retained with a snap ring on both sides. The reason for using a snap ring on both sides of the spherical bearing is so that the ID of the outer sleeve is as big as possible to allow for as much misalignment as possible.
93gsxturbo wrote:
Like this.
That is essentially what I'm doing except instead of the 2 internal snap rings, I am boring the cylinder so one side will be a shoulder, the other a snap ring.
Will you have enough articulation like that?
93gsxturbo wrote:
Will you have enough articulation like that?
Yeah - the control arm will be fixed in the plane of motion for the bearing - so the only misalignment is toe adjustment. By my pencil scribble reckoning I will have +/- 5 to 6 degrees with a 5/8 bolt, 3/4 sleeve so that ought to be more than enough to adjust for any small assembly issues aligning the control arms on a home-made subframe. I suppose if I'm wrong by more than that I probably shouldn't be doing this so... either way it will be a successful experiment 
I was going to suggest threading the bore on each side, and then screwing in a thinwall threaded bushing from each side.
1-1/4 (pipe size, not inches) straight pipe thread is 1.660" nominal diameter, and recommended drill size is 1-33/64, which works out to 1.515", so your bore is already spot on:
http://www.engineeringtoolbox.com/american-standard-straight-pipe-threads-d_1520.html
For the bushings, get a piece of 1-1/4 (pipe size, not inches); straight threaded steel pipe, use a lathe to cut rings from it, maybe 1/4" or 3/8" wide, enough to cut a couple of slots in the edge to allow tightening/loosening with a simple spanner.
Heck, you might even get away with using tapered pipe, which means you could get the supplies and taps from Home Depot/Loews/Harbor Freight, maybe even rent the pipe tap.
A piece of shim stock (0.001", 0.004" ?) wrapped around the outside of the spherical bearing (as many turns as needed) would allow you to eliminate radial play in the housing bore.
