Defining tangency with GD&T?
Defining tangency with GD&T?
(OP)
I have a solid cylindrical part with a diameter of .375" and a SR.275" at one end with a blend radius of SR.050" between the dia. and spherical radius. The SR.275 and SR.050 blend radius must be tangent, but we cannot figure out how to specify this with GD&T without having an unreasonable profile tolerance. The boss wants a profile tolerance of .0001, but the .275R and .050R can vary +/-.002 each. Any ideas?





RE: Defining tangency with GD&T?
Hard for me to tell without a pic.
Chris
Systems Analyst, I.S.
SolidWorks/PDMWorks 05
AutoCAD 06
ctopher's home site (updated 06-21-05)
FAQ559-1100
FAQ559-716
RE: Defining tangency with GD&T?
RE: Defining tangency with GD&T?
The difference is not typically a concern until finer toleraces are needed, then use a CR along with a suitable size tolerance. I love Surface Profile, but this isn't a good use for it as it sets up a symmetrical tolerance zone which conflicts with the CR tolerance zone.
This was not the case in '82, when CR did not exist and R had the meaning that CR now has. (Fig. D-2)
Hope that helps.
Jim Sykes, P.Eng, GDTP-S
Profile Services
CAD-Documentation-GD&T-Product Development
RE: Defining tangency with GD&T?