CVD measurements

[Hcp22]

Hi guys

I would be glad if you could help me out measuring different manufactory’s CVD’s, or maybe this is already done? It’s rather expensive to by several pairs of CVD’s just do discover that they are 5 mm to long or 5 mm too short for your project…
I made I suggestion what measurements you need, plus manufacturer and part #
Is there anything else that would be helpful, more measurements for an example, or thread?

A = Length
B = Length
C = Diameter
D = Diameter

[Coelacanth]

Probably the most important spec is the pin-to-pin (or pinhole) length, which seems to be missing from your diagram. CVDs are upgrades of dogbones, and the most important dimension of a dogbone is the pin-to-pin length.

EDIT: Another important consideration is what kind of joint is used at the CVD end. Some CVDs have a ball & pin at the joint, while others have a cup, with the ball & pin being on the outer, axle side. I've made the mistake of buying a CVD that was almost the exact dimensions I needed, but wanted to change the axle end--only to discover it had the opposite joint arrangement, and I couldn't swap the axles because it had a cup end instead of the ball & pin end.

[Hcp22]

Thanks for the input
My simple drawing was meant to look like a CVD, not a dog bone.

So if you measuring your dogbones and wheel shafts you know your A length. Then you measuring outer distains between your bearings, then you got the B length. So please correct me if I’m wrong thinking…

[Coelacanth]

There are just so many variables with CVDs. The length of the cross-pins, the diameter of the cross-pins, some have tapered axles instead of straight for mounting with hex hubs and a press-fit instead of using holes & cross-pins, the length of the threaded portion of the axles...not to mention the all-important 'bone & axle lengths. Even then I'm sure I'm missing more variables.

[Hcp22]

Will this cover it if we just talking about CVD’s with cross pins?

A = Length
B = Length
C = Diameter
D = Diameter
E = Diameter
F = Length
G = Length

CVD 2.jpg (12.39 KiB) Viewed 1469 times

CVD 2.jpg (12.39 KiB) Viewed 1469 times

[Coelacanth]

I added a few other measurements that would be important to a breakdown of a CVD's specs.

[mrhemi1971]

Once we gather all the information, this should be made into a separate database or list by size. From what I've seen, MIP used a common universal joint and pin with different bone, and axle lengths. Pictures would be nice too!

[Hcp22]

I added a few other measurements that would be important to a breakdown of a CVD's specs.

Any more input or can we agree upon this?
I think the measuring should be in metric or imperial, but I prefer both if possible.

A = Length
B = Length
C = Diameter
D = Diameter
E = Diameter
F = Length
G = Length
X = Length
Y = Length
CVD = Length
Thread

[Hcp22]

One other thing, this thread should maybe be located in “R/C Tech Forum”

[Mr. ED]

CVD's are a real pain to compose unless you can stay with the same brand, and even then... A couple more differences I noticed: set screw thread type, ball on the axle vs cup on the axle, outer-diameter of the small cilinder with the setscrew