Runout to threads. Possible??
Runout to threads. Possible??
(OP)
Questions for GD&T'ers: Can runout or
total runout be applied to Threads (external or internal). My GD&T books only shows examples to Circular surfaces O.D.'s
total runout be applied to Threads (external or internal). My GD&T books only shows examples to Circular surfaces O.D.'s





RE: Runout to threads. Possible??
RE: Runout to threads. Possible??
From my experience, inexperienced engineers and designers are tempted to use threads for centring two parts. This is a bad approach. The better is to add a short accurate cylindrical part to the threaded part and use a loose (2A, 2B or even 1A ,1B class) thread. The cylindrical part will be used for centering and the loose thread for connection.
RE: Runout to threads. Possible??
Jim Sykes, P.Eng, GDTP-S
Profile Services
CAD-Documentation-GD&T-Product Development
www.profileservices.ca
RE: Runout to threads. Possible??
I would never use runout on threads.
Chris
Systems Analyst, I.S.
SolidWorks 06 4.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 06-21-06)
RE: Runout to threads. Possible??
It is not good practice to reflect threads since the areas of contact are so small that whatever result one obtains would only achieve about a 70% confidence.
Even if one uses a flat contact on the indicator, it is difficult to check and I am talking about an OD thread.
Don't even think about applying on internal threads. It won't work.
Hope this helps.
RE: Runout to threads. Possible??
RE: Runout to threads. Possible??
RE: Runout to threads. Possible??
I am in agreement with others here that positional tolerance would be a much better control.
RE: Runout to threads. Possible??
that Runout or Total Runout cannot be used on a threaded integral stud.
Or an internal thread say 2 1/4 size in a circular part. I work with some old
school prints and co-workers who may have heard or read GD & T and
misinterpret. How to tell them the truth. Why bother. A precession arbor
is what the shop uses to check this. I would stick to true position and perpendicularity to a
Datum if need be. For future experience with another company.
RE: Runout to threads. Possible??
I'm going to runout of this thread now.
Chris
Systems Analyst, I.S.
SolidWorks 06 4.1/PDMWorks 06
AutoCAD 06
ctopher's home (updated 06-21-06)