C2/C3 Spindle setup tool - question

[MYBAD79]

Here's a photo of the rear wheel bearings and spacer and shim installed on a slip fitted spindle (setup tool):



Why can't this setup tool simply be a f.e 3/4" bolt ?

Unfortunately I missed the opportunity to take the same picture with the bearings setup on a bolt... unless I'm missing something here i don't see why the tight radial fit is necessary. To measure endplay it should be just as good and just as precise to use a long 3/4" bolt and washers so that the torque is applied to the inner race of the bearing.

not ???

 

[stinger12]

i don't see why the tight radial fit is necessary

The tight fit might be necessary to insure that the nut being tightened is parallel to the bearings, so it doesn't put more "pressure" on one side of the sleeve/shim. I mean, the measurement is in the thousandths, so I guess it could make a difference. This is just an idea. Maybe Mike or Gary will chime in.

 

[MYBAD79]

The tight fit might be necessary to insure that the nut being tightened is parallel to the bearings, so it doesn't put more "pressure" on one side of the sleeve/shim. I mean, the measurement is in the thousandths, so I guess it could make a difference. This is just an idea. Maybe Mike or Gary will chime in.

You have a good point but think about it: if the shim or spacer is not parallel then the tight radial fit will only make the side loading worse. With a tight radial fit it you measure the tightest spot.
Assuming you mic'ed the shim, spacer and the two bearings and all parts are parallel it should be ok to use a bolt without the radial fit.

The bolt head needs a collar that fits the inner race, on the other side there must be a washer with a collar that fits the opposite side inner bearing race.

Now... the two ends of the bolt must be parallel.... machined to higher standards that I would expect from a $1.37 Homedepot bolt.... but anyways... let's assume the bolt and the washers are machined parallel...

is the tight radial fit important or not ??

 

[stinger12]

The tight fit might be necessary to insure that the nut being tightened is parallel to the bearings, so it doesn't put more "pressure" on one side of the sleeve/shim. I mean, the measurement is in the thousandths, so I guess it could make a difference. This is just an idea. Maybe Mike or Gary will chime in.

You have a good point but think about it: if the shim or spacer is not parallel then the tight radial fit will only make the side loading worse. With a tight radial fit it you measure the tightest spot.
Assuming you mic'ed the shim, spacer and the two bearings and all parts are parallel it should be ok to use a bolt without the radial fit.

The bolt head needs a collar that fits the inner race, on the other side there must be a washer with a collar that fits the opposite side inner bearing race.

Now... the two ends of the bolt must be parallel.... machined to higher standards that I would expect from a $1.37 Homedepot bolt.... but anyways... let's assume the bolt and the washers are machined parallel...

is the tight radial fit important or not ??

Hey, you do have a point there. We need Mike and Gary to chime in - they'll know for sure.

 

[MYBAD79]

Hey, you do have a point there. We need Mike and Gary to chime in - they'll know for sure.

Yes, we need the experts to tell us why it would or wouldn't work... I've had brainfarts in the past ... you know when you think you have a brilliant idea and it takes somebody else "outside the box" to bust your bubble..LOL

I have doubts about the 100lbs/ft as well.... if the bearings and the shim/spacer are all parallel then it shouldn't matter if you torque it to 20 or 100 lbs/ft... when the parts are making contact it's a tight as it gets... it's not like you're compressing the bearing races, shim or spacer by torquing it to 100lbs/ft ....

 

[GTR1999]

I must have missed something, this 3/4 bolt is going to take the place of the spindle setup tool? No fit on the bearing ID?

 

[MYBAD79]

Correct, no fit on the bearing ID.

Assuming that the two surfaces that contact the bearings' inner races are parallel.... what is that tight fit on the bearing ID good for ?

OK, I know it is very convenient to simply use an old slip fitted spindle or the setup tool. Does the setup tool actually have a tight fit on the bearing ID ? I've never used one so I dunno...

 

[big_G]

Correct, no fit on the bearing ID.

Assuming that the two surfaces that contact the bearings' inner races are parallel.... what is that tight fit on the bearing ID good for ?

OK, I know it is very convenient to simply use an old slip fitted spindle or the setup tool. Does the setup tool actually have a tight fit on the bearing ID ? I've never used one so I dunno...

My Ecklers set-up tool has a good slip-fit. Maybe .002-.004 clearance.

 

[MYBAD79]

OK, I am guessing that the slip fit is a convenience... if you make this tool on a lathe then there's no reason NOT to make the OD fit the bearing ID.... now... would a bolt/washer/nut work just as good ... maybe....

I'll take a few pics when I take my other TAs/bearings apart.... the old bearings, shim, spacer setup on a bolt.... maybe then I'll see why it won't work.... :rain:

 

[Sky65]

I would think the purpose of the slip fit to the ID of the bearings is for alignment purposes. To make sure the bearings, spacer and shims are all in the the correct line, as they would be with the spindle installed, to get an accurate reading. The final spec is only a couple thou isn't it? Maybe a piece of PVC pipe of the proper OD would work for as the alignment aspect and your 3/4" bolt to achieve proper assembly torque? I guess the test for the bolt would be repeatable results.

 

[GTR1999]

The setup tool or old spindle will support the ID, which I like, so that when I check endplay I know the only movement I'm getting in the bearings, the loose ID leaves room for side play and a false reading in my opinion. Granted I've never attempted to do it that way but then why would I? The setup tool I have is the one with kurled handle so I can really load it to see what the endplay is. I recommend using the setup tool or making one with a slip fit. I haven't measured mine but I doubt there's more then 001-0015" slip fit.

 

[mrvette]

I been holding fire on this thread as I have in the past agreed with Jim/Turtlevette about making the entire assy a slip fit...

this photo in the first post here proved what I thought, but never having had one of these assy's apart myself, never seen a naked spindle or the apparent bearing spacing, I had always ASSUMED they bearings were much closer together like a C4 hub, which I have changed a couple....so I get to the purchase on the bearings is much greater than I"d imagined, and so it further reinforces my agreement with Jim/Turtle that they do not need be pressed fitted...a simple concept of the same way the front wheels are done is sufficient....I have NO idea what was on the mind of the GM guys that designed that pressfit thing, and I can not see any reason for it....

friggin wheel is a wheel, the axel rotating in the inner race or the wheel rotating on the outer race.....same friggin differance, don't matter about the bearing press fitted or whatever....

surely the braking affects and cornering affects over the bearings are much more than in the rear....the simple act of spinning the axel/tire under torque has almost no loading on the bearings....changes the load from vertical to some other point on the compass....

:beer:

 

[MYBAD79]

The one spindle assembly that I took apart and that was slip fitted had about .120" worn off the spindle flange. I am not sure how this happened but due to the spline it is impossible that the flange rotates at a different speed than the spindle.... therefore I must assume that either the inner bearing race froze or got stuck so that the spindle rotated but the bearing did not.... OR .. it hammered (taking a beating when the wheel was side loaded) and increased the axial clearance over time.... I am really curious what kind of noises it made when driving the car like this...LOL

 

[mrvette]

The one spindle assembly that I took apart and that was slip fitted had about .120" worn off the spindle flange. I am not sure how this happened but due to the spline it is impossible that the flange rotates at a different speed than the spindle.... therefore I must assume that either the inner bearing race froze or got stuck so that the spindle rotated but the bearing did not.... OR .. it hammered (taking a beating when the wheel was side loaded) and increased the axial clearance over time.... I am really curious what kind of noises it made when driving the car like this...LOL

Jeez dude, that's EASY, the PAINFUL kind......:crap: