Engineers Edge
Sphere form tolerance Question
Post Reply   Forum
Posted by: Hup23Hup

04/16/2007, 04:55:13

Author Profile
eMail author
Edit


I am measuring a sphere on a CMM and the sphere is measuring too big. However, take more points and it averages out O.K.
When I measured the form of the sphere in is .060 of a mm. This I believe is way too big. The drawing does not state a sphere form tolerance. What is a recommended sphere form when the drawing does not specify one?

Thanks,
M








Post Reply
Tell a Friend (must be logged in)
Alert Admin About Post
View All   | |

Replies to this message

Re: Sphere form tolerance
Re: Sphere form tolerance -- Hup23Hup Post Reply Top of thread Forum
Posted by: Kelly Bramble

04/16/2007, 07:52:16

Author Profile
eMail author
Edit

Regardless of which three points your measure from, if you measure larger than the maximum material condition given by the limits of size, then it is too large. If there is not a form tolerance specified, then one is not measured. If the drawing is interpreted per ASME Y14.5M-1994, then MMC is a boundary that may not be encroached or violated (part measures larger than) by the combined effects of form and size. So, if the part is manufactured at MMC it has to be a perfect sphere. Technically, the sphere is form controlled by default from the limit tolerances. The part can vary between MMC and LMC and this is the form limits as well.







Post Reply
Tell a Friend (must be logged in)
Alert Admin About Post
Where am I? Original Top of thread | |
Re: Re: Sphere form tolerance Agree
Re: Re: Sphere form tolerance -- Kelly Bramble Post Reply Top of thread Forum
Posted by: Hup23Hup

04/17/2007, 07:54:42

Author Profile
eMail author
Edit

Thanks Kelly.
V. Informative and clear.

Hope I can help you out sometime.








Post Reply
Tell a Friend (must be logged in)
Alert Admin About Post
Where am I? Original Top of thread

Powered by Engineers Edge

© Copyright 2000 - 2019, by Engineers Edge, LLC All rights reserved.  Disclaimer