Ellipses
Ellipses
(OP)
What is the proper way to dimension a true ellipse.
Wes C.
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When they broke open molecules, they found they were only stuffed with atoms. But when they broke open atoms, they found them stuffed with explosions...





RE: Ellipses
Chris
Systems Analyst, I.S.
SolidWorks/PDMWorks 05
AutoCAD 06
ctopher's home site (updated 06-21-05)
FAQ559-1100
FAQ559-716
RE: Ellipses
Best Regards,
Heckler
Sr. Mechanical Engineer
SW2005 SP 5.0 & Pro/E 2001
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RE: Ellipses
RE: Ellipses
Some NC programs can interpolate the true path required from the major & minor axes lengths, others will need multiple co-ordinates to interploate between.
Helpful SW websites FAQ559-520
How to get answers to your SW questions FAQ559-1091
RE: Ellipses
I usually dim the major axis, and minor axis and I'll call out the degree to which the elipse lies as a reference, but today I was tasked to find the convention, and I can't find it in any of my books...
Wes C.
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When they broke open molecules, they found they were only stuffed with atoms. But when they broke open atoms, they found them stuffed with explosions...
RE: Ellipses
Flores
RE: Ellipses
Regards,
Cory
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: Ellipses
Orientation is best defined by the angle of the major/minor axes relative to another line.
Location is best determined by ellipse center. It would also be possible to locate w.r.t. one or two points on the ellipse.
RE: Ellipses
For tolerancing the size of the ellipse, you theoretically can use formulae which increases and/or decrease the distance, and locate it using a positional tolerance on the boundary of the ellipse (ASME Y14.5M-1994 5.10.1 & Fig. 5-47)
I would just use the surface profile which provides a symmetrical offset from the theoretical (basic) geometry thereby controlling both size and location. You can even control the size & location different wrt one datum.
Jim Sykes, P.Eng, GDTP-S
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