For both open and CMM setups - the following is general best practice for CMM's per ISO.
I have two question regarding runout tolerance:
1. Is this any standard which specifies, on how many sections runout tolerance shall be verified?
2. Normally cylinder axis is used as datum for run-out. Can a Circle point be used as datum or not? for example for washers etc.
Any ideas please.
Last edited by Kelly_Bramble; 12-12-2014 at 10:32 AM.
For both open and CMM setups - the following is general best practice for CMM's per ISO.
Can a Circle point be used as datum or not? for example for washers etc.
Yes one can use a point derived from a circle if that is all that can be obtained. In general datum's specified should be large enough to function as a stable mating feature as well as a datum of sufficient size to measure from.
You should always attempt to establish an axis datum from as many circles as you can or is reasonable. Don't settle for a circle point if there is plenty of cylindrical area to establish a complete datum and more stable datum axis.