Over Ball Ø Mdk (OBD) measurement!

[Hidk]

I have a part which have 36 splines. If space width (measured gauge), Minor Ø and Major Ø (measured CMM) are within tolerance.

Is there any possibilities Over Ball Ø Mdk are out of specification?

 

[mfgenggear]

OP
Which specification.
The same ansi specification
Max effective can be only measure
With a go gage on external.

The measurement over wires are calculated from max and min actual.
And the nax actual measureme t could be over size and yet the go gage does accept, and that is acceptable.
I will explain in a follow up post

 

[mfgenggear]

The go gage verifies multiple attributes. Parallel, (lead) tooth to tooth, total composite error, and involute. If all these attributes are very close, spline can slightly ovè size but will accept the go gage.
Means parts will assemble.

 

[spigor]

The answer is yes. This can be caused by a number of factors, including profile angle errors, pitch errors and tooth line errors. The Mdk measurement tends to indicate a wider space than the gauge.

 

[mfgenggear]

Spigor
How have been, been gone a while.

 

[spigor]

I've been around, I only write when I feel I have something useful to share.
And how about you, are the headaches gone?

 

[mfgenggear]

Spigot
I am feeling better, and I am exercising, I walk my dogs a lot.
Trying to stay healthy.
As we get older it a task.

 

[Hidk]

Thank you very much for your comment.
My main challenge is to reduce the first off time. Part is for internal drive, no of splines are 36, We measured OBD, internal minor / major Ø by CMM at 2 levels. It took 10 / 12 minutes for OBD. We measure Effective / Actual space width by gauges. Do you think this gauge will cover profile and lead also.
Again, If Effective / Actual space width, internal minor and major Ø are within tolerance, do we really need to verify the OBD. Please see attached measured values.

One more request can I have your e-mail address, as I am new in this subject.

 

[Hidk]

Thank you very much for your comment.
My main challenge is to reduce the first off time. Part is for internal drive, no of splines are 36, We measured OBD, internal minor / major Ø by CMM at 2 levels. It took 10 / 12 minutes for OBD. We measure Effective / Actual space width by gauges. Do you think this gauge will cover profile and lead also.
Again, If Effective / Actual space width, internal minor and major Ø are within tolerance, do we really need to verify the OBD. Please see attached measured values.

One more request can I have your e-mail address, as I am new in this subject.

 

[mfgenggear]

Op
Sorry I can not ,
Please create a pdf instead of excel sheet.
If there are go and no go gages
Measure between for internal or measurement over wires, for external is not required. Acceptance can be with gages. Yes attributes are all inclusive
Except pitch diameter run out, major or minor diameter. And the root filled radii.

 

[mfgenggear]

As I stated before max effective on an external can not be measured with wires or balls.
Same goes for internal min effective size.

 

[Hidk]

Please try this picture.
We are using seizer type Effective / Actual space width gauges.
Thank you

 

[spigor]

The tolerances you posted look strange. If you posted all the specs, I could run them to see if they are ok.

 

[Hidk]

Thank you very much Spigot.
Can you send me your e-mail address at khanz.041115@gmail.com

 

[Hidk]

Yes, we are using control tolerances from quality.

 

[spigor]

*secret data received via email*

It looks like a serration, not an involute spline. I calculated dimensions between balls (not over balls, it is an internal) and the results match the data on the drawing. So, no easy answer, you probably need to dig until you find the cause of these two measuring methods giving different results.