Turning CV Joints into Bearing Surfaces

[Nate Notta]

Hi,

We are thinking about machining our CV joints in the rear to act as a bearing surface, so they can sit inside the upright.
I know I've seen it done before, but what schools have done it?
Any thoughts on the topic? There seems to a lot of packaging and assembly issues.

Nate Nantais
UofW 2003/2004 Team

[Jimboblofski]

we have done that for the last few years at the university of hertfordshire it is a nice packaging solution. however the wheel bearings that you have to use are huge and our ones are about £70 each! you need four of them!

if your clever you can get som nice and tiny cv joints from a small italian car manufacture http://fsae.com/groupee_common/emoticons/icon_wink.gif

[Nate Notta]

Well we already have our CV joints, and they're not tiny but we're hoping they'll work.
Do you have any pics?

[John McCarthy]

I believe the University of Western Australia did something along those lines in their 2003 (current) car. Although the photos I have aren't really good because they run outboard brakes which sit inside the uprights, obscuring most of the view of the hubright.

Hope this helps.

Cheers!

Technical Manager,
QUT Motorsport.
www.qutmotorsport.com (http://www.qutmotorsport.com)

[bigtoyota9]

we did something along those lines last year for 2003 and it worked out great. It cleans everything up and in our case saved us some wieght. I have to agree with jim on the bearings I think ours were something like $175 per bearing from SKF, but you can get them sampled if you talk to the right people.

[Sam]

Yeh. WA's hubrights.. very funky indeed gents!

Sam Graham
Random Stooge 2004
UQ Racing

[All Wheeler]

We at Newcastle had our wheel bearings on our CVs, and they weren't little. I'm interested to know what kind of bearings you are using. If you can get your hands on an NTN deep groove rollerbearing catalogue, you might find that you can get away with running deep groove roller bearings. Ours were only AU $90 each.

[ben]

We run a pair of angular contact ball bearings on each rear wheel. They are 95mm od with a 75mm bore from INA bearings (www.ina.de) (http://www.ina.de)).
We then run a integrated hub/CV outer within these.

Ben

University of Birmingham
www.ubracing.co.uk (http://www.ubracing.co.uk)

[All Wheeler]

Not necessarily relevant to this thread, but didn't want to start another one on CV joints.
Just wondering if anyone has a DXF of their CV joint outer cage or trunnion so that it could be wire cut. Of particular interest is the size 5VL joints that I believe are available through Unidrive. If anyone has a scanned picture of the section of the outer cage of this joint that could be scaled and have a DXF overlaid, that would also be pretty sweet. I'm not strictly on a team so to speak, but I am trying to figure out the logistics of developing a slim torque sensing differential/sprocket, where the CV outer profile is EDM cut into the side gears of the diff, such that the sprocket, diff and inner CV joints are the one unit. Interestingly enough, the inner CV would effectively be a bearing surface, and the number of components and overall weight should be pretty decent. Anyone who might be interested in corresponding with me on this, please reply or contact me on my studentmail account which will probably expire in the coming weeks.
douglas.teyhan@studentmail.newcastle.edu.au
Dou

[TA]

Not sure how relevant this is but standard Cooper S (old) and 84-up disk brake Mini's use an outer CV with the bearings riding directly on the CV. Use a very inexpensive ($5.00) Timken wheel bearing as well. Easy to source, at least five North American sources off the top of my head. About $60 US each.

If anyone's interested I have a spare CV in the shop I can photograph and I can dig up the bearing part# as well.

Cheers, Ted

[TA]

Actually, Nate, didn't realise you were in town until after I posted. If you'd like, give me a call on my cell 818-0033. I can bring a hubright, cv and driveplate by the CARE building for you to look at.

Cheers, Ted

[Denny Trimble]

Yeah, I'd like to see a photo of that CV. What size splines does it take (i.e. what size halfshaft can you run)?

University of Washington Formula SAE ('98, '99, '03, '04)

[Nate Notta]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by ben:
We run a pair of angular contact ball bearings on each rear wheel. They are 95mm od with a 75mm bore from INA bearings (http://www.ina.de).
We then run a integrated hub/CV outer within these.

Ben

University of Birmingham
http://www.ubracing.co.uk<HR></BLOCKQUOTE>

Ben,
I'm assuming those are the i75, o95, 10mm width bearings... Did you get away with using only two of those in each wheel? The force ratings are only around 600lbs axially...
Anybody think it's necessary to use three - two for the lateral direction that will experience the higher loads?

Nate
UofW 2004

[TA]

http://www.andkilde.com/minicv2.jpg

This is the Cooper S CV ,internal spline is 13 spline, not sure what the outer is, I'll measure when I get a chance to get in to the garage.

OEM wheel bearing is Timken #LM67049a, bit pricey, usually special order.

Standard tapered roller bearing
Timken #LM67048 is much cheaper, and in stock at just about any bearing house.

Only difference between the two is the 048 has a chamfered mating face and the mating face on the 049a is dead square. Fitting dimensions are identical.

Cheers, Ted

[ben]

<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by NateNantais:
Ben,
I'm assuming those are the i75, o95, 10mm width bearings... Did you get away with using only two of those in each wheel? The force ratings are only around 600lbs axially...
Anybody think it's necessary to use three - two for the lateral direction that will experience the higher loads?

Nate
UofW 2004<HR></BLOCKQUOTE>

We ran two of these per rear wheel last year with no problems at all. We intend to run the same set up again on the new car.

Ben

University of Birmingham
www.ubracing.co.uk (http://www.ubracing.co.uk)

[Denny Trimble]

Thanks for the photo. Since mini's are rare over here, I have a couple more questions http://fsae.com/groupee_common/emoticons/icon_smile.gif What's the ID of the female spline? How much does that weigh?

Thanks a bunch,
Denny

University of Washington Formula SAE ('98, '99, '03, '04)

[TA]

http://www.mowog.on.ca/21A1270.JPG
Cooper S drive flange.

OK

Axle is 19 spline, .875" O.D.
Overall length, to base of threads, 5.25"
Length of threads, 1"
CV shaft, 1.25" O.D., 7/8 UNF
CV shaft length, smooth, 1.9" splined, 1.25"
Major O.D. 2.75"
Male spline, 29 spline, 1.25" O.D.


Guesstimate weight, 1.5 kg

Cheers, Ted