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JCByrd24
10-24-2018, 11:49 AM
Does anyone out there have an experience with CV joints in custom applications. I've got an a single joint shaft in a small AG application and want to upgrade to a CV joint. I've never seen a bare joint intended to be grafted onto your own shaft, and I'm worried one intended for a small car or UTV would be hardened and not react well with the machining and welding involved to fit it to my required end fittings. Any knowledge on the subject would be greatly appreciated. This is not something I'm in desperate need of and a double cardan u-joint version of the shaft is available from the dealer for ~$500 so nothing worth paying a custom shop to do. I'm in it for the project and reduced vibration but don't want to go down a path that is bound for failure.

Thanks

Mark Rand
10-24-2018, 12:09 PM
There are people out there that sell bare ones. You would still need to machine appropriate splines and flanges on the shafts, but that's not hard compared with making the CV joint!

This is a British firm I found (http://race.parts/Catalogue/Drivetrain/CV-Joints). I'm sure there are others out there.

MattiJ
10-24-2018, 12:26 PM
Inner CV joint on many cars(Audi, VW) is with a bolt-on flange that could be easy to repurpose.

Might be easier to cut off the spline shaft from original driveshaft and weld it to your own shafting instead of cutting the splines.
This is quite common "hack" in extreme engine swaps and works OK unless you really punish the driveshafts with shock loads.

3 Phase Lightbulb
10-24-2018, 12:49 PM
Flange type CV joints like MattJ mentioned are very easy to repurpose. For a sand rail/buggy that I designed and built, I used Porsche 920 CV joints (due to maximum angle they provide) but VW Type 1 or type 2 CV joints also work well for many applications provided you don't need severe angles. I cut the axle flange off and welded it to a splined GM type stub axle to fit into the torsion differential. So I've got a GM torsion diff being powered with a sprocket (instead of the ring gear), driving out GM splined stub axles welded to Porsche 920 CV flanges, bolted to 920 CV joints, then on the bearing carrier side, I cut out a VW type 2 bus bearing carrier and welded that into my custom 5-link uprights. I then use a standard VW type 2 wheel axle and VW type 1 disc rotors on the final drive.

http://www.bbssystem.com/pictures/920cv.jpg

And the results were great :)

http://www.bbssystem.com/pictures/badass.jpg

JCByrd24
10-24-2018, 01:45 PM
Thanks guys, now we're getting somewhere!

paul463
10-24-2018, 01:46 PM
Does anyone out there have an experience with CV joints in custom applications. I've got an a single joint shaft in a small AG application and want to upgrade to a CV joint. I've never seen a bare joint intended to be grafted onto your own shaft, and I'm worried one intended for a small car or UTV would be hardened and not react well with the machining and welding involved to fit it to my required end fittings. Any knowledge on the subject would be greatly appreciated. This is not something I'm in desperate need of and a double cardan u-joint version of the shaft is available from the dealer for ~$500 so nothing worth paying a custom shop to do. I'm in it for the project and reduced vibration but don't want to go down a path that is bound for failure.

Thanks

Spend a few hours in a boneyard, paying particular attention the AWD cars and SUVs. A lot of them have CV joints on the drive shaft to the rearend. Those would be easy to re-purpose since they are already made to be welded to a driveshaft tube.

ikdor
10-24-2018, 02:15 PM
Since not all drive shaft material likes welding you could also cut the shaft and braze it into a tube.

3 Phase Lightbulb
10-24-2018, 02:57 PM
Actually, I remember eBay being great for buying most of the stuff I needed. There were plenty of CV joints, CV axles, new/used/rebuild kits, etc. The biggest problem I had was getting "stub" axles with CV flanges to fit inside the torsion diff. For that, I ended up buying a complete Z-28 rear end and pulled the full size axles out of it and just cut off the splined ends so I could weld those splined ends directly to a CV flange.

Also, another nice feature with CV axles is you get a good inch or two of expansion/contraction so the distance between the actual CV joints can vary a bit.

MattiJ
10-24-2018, 03:03 PM
Since not all drive shaft material likes welding you could also cut the shaft and braze it into a tube.

AFAIK Most (wheel) drive shafts on european cars are something like 1045 at minimum so preheat would be preferred in any case when welding.

3 Phase Lightbulb
10-24-2018, 03:10 PM
I'm worried one intended for a small car or UTV would be hardened and not react well with the machining and welding involved

You will want to machine the axle or hardened components with solid carbide end-mills or inserts. I made the mistake of trying to initially cut a GM axle with my bandsaw and immediately destroyed a blade (duhhh). I ended up doing a rough cut with a chop saw then cut to size with carbide tooling in the mill/lathe. Pure carbide endmills cut into the hardened axle as if it was aluminum. HSS instantly destroyed itself (another initial mistake I made).

Black Forest
10-24-2018, 03:30 PM
Actually, I remember eBay being great for buying most of the stuff I needed. There were plenty of CV joints, CV axles, new/used/rebuild kits, etc. The biggest problem I had was getting "stub" axles with CV flanges to fit inside the torsion diff. For that, I ended up buying a complete Z-28 rear end and pulled the full size axles out of it and just cut off the splined ends so I could weld those splined ends directly to a CV flange.

Also, another nice feature with CV axles is you get a good inch or two of expansion/contraction so the distance between the actual CV joints can vary a bit.

I don't want to hi-jack this thread but could you give more info on the differential with the sprocket? It looks as though it would fit a project I have been working on.

MattiJ
10-24-2018, 03:35 PM
OT but maybe relevant tip:
Hub bearing units can be also quite handy for repurposing
https://www.amazon.com/ECCPP-Bearing-Assembly-Bonnevile-Century/dp/B00UMU2W7M/ref=sr_1_7?s=automotive&ie=UTF8&qid=1540409556&sr=1-7&keywords=Hub+bearing

3 Phase Lightbulb
10-24-2018, 04:29 PM
I don't want to hi-jack this thread but could you give more info on the differential with the sprocket? It looks as though it would fit a project I have been working on.

I bolted on a motorcycle sprocket to the GM automotive differential (torsion diff). A ring gear is normally normally bolted onto the diff but since I was powering my buggy with a motorcycle engine, and wanted a bullet prof differential, converted it into a sprocket driven differential. I also built an aluminum cover that slips over the diff to allow me to fill it with oil since it normally sits in an oil filled pumpkin within an axle housing but not in this case.

Here are a bunch of pictures from when I built everything.

http://www.bbssystem.com/pictures/rear_end_1.jpg
http://www.bbssystem.com/pictures/rear_end_2.jpg
http://www.bbssystem.com/pictures/rear_end_3.jpg
http://www.bbssystem.com/pictures/rear_end_4.jpg
http://www.bbssystem.com/pictures/rear_end_5.jpg
http://www.bbssystem.com/pictures/rear_end_6.jpg
http://www.bbssystem.com/pictures/rear_end_7.jpg
http://www.bbssystem.com/pictures/rear_end_8.jpg
http://www.bbssystem.com/pictures/rear_end_9.jpg
http://www.bbssystem.com/pictures/rear_end_10.jpg
http://www.bbssystem.com/pictures/rear_end_11.jpg
http://www.bbssystem.com/pictures/rear_end_12.jpg
http://www.bbssystem.com/pictures/rear_end_13.jpg
http://www.bbssystem.com/pictures/rear_end_14.jpg
http://www.bbssystem.com/pictures/rear_end_15.jpg
http://www.bbssystem.com/pictures/rear_end_16.jpg
http://www.bbssystem.com/pictures/rear_end_17.jpg
http://www.bbssystem.com/pictures/rear_end_18.jpg
http://www.bbssystem.com/pictures/rear_end_19.jpg
http://www.bbssystem.com/pictures/rear_end_20.jpg
http://www.bbssystem.com/pictures/rear_end_21.jpg
http://www.bbssystem.com/pictures/rear_end_22.jpg
http://www.bbssystem.com/pictures/rear_end_23.jpg
http://www.bbssystem.com/pictures/rear_end_24.jpg
http://www.bbssystem.com/pictures/rear_end_25.jpg
http://www.bbssystem.com/pictures/rear_end_26.jpg
http://www.bbssystem.com/pictures/rear_end_27.jpg
http://www.bbssystem.com/pictures/rear_end_28.jpg

Black Forest
10-24-2018, 04:59 PM
I bolted on a motorcycle sprocket to the GM automotive differential (torsion diff). A ring gear is normally normally bolted onto the diff but since I was powering my buggy with a motorcycle engine, and wanted a bullet prof differential, converted it into a sprocket driven differential. I also built an aluminum cover that slips over the diff to allow me to fill it with oil since it normally sits in an oil filled pumpkin within an axle housing but not in this case.

Here are a bunch of pictures from when I built everything.

http://www.bbssystem.com/pictures/rear_end_1.jpg
http://www.bbssystem.com/pictures/rear_end_2.jpg
http://www.bbssystem.com/pictures/rear_end_3.jpg
http://www.bbssystem.com/pictures/rear_end_4.jpg
http://www.bbssystem.com/pictures/rear_end_5.jpg
http://www.bbssystem.com/pictures/rear_end_6.jpg
http://www.bbssystem.com/pictures/rear_end_7.jpg
http://www.bbssystem.com/pictures/rear_end_8.jpg
http://www.bbssystem.com/pictures/rear_end_9.jpg
http://www.bbssystem.com/pictures/rear_end_10.jpg
http://www.bbssystem.com/pictures/rear_end_11.jpg
http://www.bbssystem.com/pictures/rear_end_12.jpg
http://www.bbssystem.com/pictures/rear_end_13.jpg
http://www.bbssystem.com/pictures/rear_end_14.jpg
http://www.bbssystem.com/pictures/rear_end_15.jpg
http://www.bbssystem.com/pictures/rear_end_16.jpg
http://www.bbssystem.com/pictures/rear_end_17.jpg
http://www.bbssystem.com/pictures/rear_end_18.jpg
http://www.bbssystem.com/pictures/rear_end_19.jpg
http://www.bbssystem.com/pictures/rear_end_20.jpg
http://www.bbssystem.com/pictures/rear_end_21.jpg
http://www.bbssystem.com/pictures/rear_end_22.jpg
http://www.bbssystem.com/pictures/rear_end_23.jpg
http://www.bbssystem.com/pictures/rear_end_24.jpg
http://www.bbssystem.com/pictures/rear_end_25.jpg
http://www.bbssystem.com/pictures/rear_end_26.jpg
http://www.bbssystem.com/pictures/rear_end_27.jpg
http://www.bbssystem.com/pictures/rear_end_28.jpg


Thank you. Very cool buggy!

3 Phase Lightbulb
10-24-2018, 05:02 PM
Thank you. Very cool buggy!

This was one of the first test rides after I finished building it back in 2006


https://www.youtube.com/watch?v=JCMgPKIc8eo