Total runout
Total runout
(OP)
We have a part that has two shafts opposite each other. (.187 dias.x .375 long each) Each shaft has individual datum callouts (A & B) with a total runout callout of .0005 to A-B. We have a few interpretations here on how this should correctly be inspected. At the moment we are simply placing one shaft in a "V" block and rotating it with an indicator on the opposite shaft. Use of a C.M.M. is out of the question because each part needs to be inspected, once it comes off the machine in production quantity's. Any insight would be appreciated.





RE: Total runout
Clarification required!
RE: Total runout
RE: Total runout
Best Regards,
Heckler
Sr. Mechanical Engineer
SW2005 SP 5.0 & Pro/E 2001
Dell Precision 370
P4 3.6 GHz, 1GB RAM
XP Pro SP2.0
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RE: Total runout
Dave D
RE: Total runout
Chris
SolidWorks 06 4.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 10-27-06)
RE: Total runout
RE: Total runout
RE: Total runout
The examples in tec-ease are not compatable with the problem stated. It requires an axis A-B.
Try Figs 6-49 and 6-51 of the Y14.5 Std.
RE: Total runout
Datum A is one of the .1870 dias which is a male feature. The opposite dia. of .1871 is the B datum, which is also a male feature, they are separated by a rectangular section. At each diameter callout the total runout of .0005 A B is attached. The width of the rectangular feature that separates the two shafts is .750
The part is for a military application...the whole part is critical, and very expensive for its size.
Hope this clears things up!!
RE: Total runout
I do not understand why there are A and B. Why not use just A and then give the other shaft with total run-out of 0.0005" with respect to A. Usually such a part is turned on a lathe using centering holes. This way you can get the 0.0005" run-out quite easily.
Anyway, if this is a given drawing I think you need to place both shafts on two very accurately aligned V blocks and then while you rotate the part measure the run-out on both shafts while they are supported on the two V blocks. If the part has two centering holes (one on each shaft edge) then you can use the centring holes as A-B and measure the run-out on both shafts.
I assume this is a gimbal part.
RE: Total runout
Best Regards,
Heckler
Sr. Mechanical Engineer
SW2005 SP 5.0 & Pro/E 2001
Dell Precision 370
P4 3.6 GHz, 1GB RAM
XP Pro SP2.0
NVIDIA Quadro FX 1400
o
_`\(,_
(_)/ (_)
Never argue with an idiot. They'll bring you down to their level and beat you with experience every time.
RE: Total runout
Place the datum A in a inspection grade chuck but just at the end of the diamter and not much length of the material in the chuck.
Get is digital indicator in at least .0001 or better and true up the other end. This is done by contacting the top or highest point of the diameter B which will be its C?l, then rotate the part. One will see the readings move up and down. Tap it down at the highest point and re-tighten the chuck at the other end. Continue this until you have the datum B running true (little FIM or TIR). You are now set up to datums A - B.
Take your indicator to the feature and contact it at its C/L or highest point. Rotate the part and note the extreme readings. You are taking a circular runout right now.
Move the indicator to another segment on the feature and perform the circular runout again without re-zeroing the indicator.
Move the indicator again so that you have both ends of the feature and centre measured, again, without re-zeroing.
Total runout is the combined readings from the 3 segments. If in 1 segment, the lowest reading was -.0003 and the highest reading was at the other end and it was +.0004, the total runout is .0007.
Hope this helps.
Dave D.
RE: Total runout
Are yu making reference to inspection IAW Y14.5? If so, my version of Y14.5 does not seem to support your combining of the readings to establish the total runout. It is assessed on each segment as applicable by the Feature control frame on that particular segment.
RE: Total runout
www.tec-ease.com/tips/march-03.htm
RE: Total runout
Using V-blocks would be really tough. One block would have to be higher by 1/2 the diameter difference than the other one if the diameters are different. This is rather difficult.
Having a two point contact on a datum surface is not a good as a 3 point - 120 degrees apart and better yet, a 4 point.
Dave D.
www.qmsi.ca
RE: Total runout