GD&T a cross hole in a shaft
GD&T a cross hole in a shaft
(OP)
How would one dimension a cross hole in a round shaft? One method that was presented was to use a straightness on the cross hole and two perpendicular call outs to the axis of the hole, is there a preferred method of doing this? We have not been able to find any examples of this anywhere.
Scorch
Scorch
Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats.
--Howard Aiken, IBM engineer





RE: GD&T a cross hole in a shaft
Perhaps an endface as -A- and the diameter as -B-, if orientation or 'clocking' is significant then add a -C- datum based on a feature to use for this.
fig 5-15 & 5-24 & 5-25& 5-36 in ASME Y14.5M-1994 kind of show this although they aren't great examples as they are all primarily showing something else.
Are you iso or asme or what, if asme then you souldn't really use a CL as a datum in this application.
I'm not sure what the 2 perpendiculars get you in your proposed scheme.
KENAT, probably the least qualified checker you'll ever meet...
RE: GD&T a cross hole in a shaft
Both diametrically opposed holes are assumed as 1 hole and one can confirm perpendicularity by zeroing on one hole and then centre on the other. The difference should not exceed the perpendicularity tolerance.
One could go further by calling one end datum B. Now we can place a basic dimension from datum B to the centre of the holes and the use a positional tolerance. We not only control the angle on both holes but their location.
Just some thoughts.
Dave D.
www.qmsi.ca
RE: GD&T a cross hole in a shaft
Could you state the function of the holes?
RE: GD&T a cross hole in a shaft
I agree with KENAT, just use a positional callout, but with the shaft diameter as datum "A" and an end face of the shaft or functional step (if there is one) as datum "B". The postiion tolerance will cover both centering on the shaft diametral axis and perpendiculity.
RE: GD&T a cross hole in a shaft
Scorch
Don't worry about people stealing your ideas. If your ideas are any good, you'll have to ram them down people's throats.
--Howard Aiken, IBM engineer
RE: GD&T a cross hole in a shaft
Most of my cylinders with holes are relatively short and mate at one end hence my suggestion.
KENAT, probably the least qualified checker you'll ever meet...
RE: GD&T a cross hole in a shaft