datum question
datum question
(OP)
Hi,
I have a part that I am dimensioning, and I want to make sure I am correctly using datums. Is this the correct way to use the datums A and B that are not perpendicular to each other? I can call out a basic angle between -A- and -B- and then i can dimension from the "imaginary" surface that is perpendicular to -A-? Then I can put positional tolerances on the holes wrt -A- and -B-, but in reality it is really checked to -A- and this imaginary surface?
I have a part that I am dimensioning, and I want to make sure I am correctly using datums. Is this the correct way to use the datums A and B that are not perpendicular to each other? I can call out a basic angle between -A- and -B- and then i can dimension from the "imaginary" surface that is perpendicular to -A-? Then I can put positional tolerances on the holes wrt -A- and -B-, but in reality it is really checked to -A- and this imaginary surface?





RE: datum question
RE: datum question
RE: datum question
RE: datum question
RE: datum question
RE: datum question
Basic dimensions to the cetner of the holes and then locate them (position)
Basic dimensions should come from the center of the pattern (most preferred solution)
RE: datum question
What is the scrape rate?
RE: datum question
FIG. 4-4 INCLINED DATUM FEATURES
So, in your case you can use it, but is entire non-functional approach.
RE: datum question
"The origin of the datum reference frame may be established at the center of the pattern of the datum feature simulator…, or at any other location defined with basic dimensions relative to the datum feature simulator…”
I believe this has been discussed a couple of times on this forum by people with a lot more experience than I have. Here are some relevant threads you can look through
http://www.eng-tips.com/viewthread.cfm?qid=364740
http://www.eng-tips.com/viewthread.cfm?qid=283384
RE: datum question
@M4C7, thanks for pointing out that the part does not need to be dimensioned off of the center of the holes, this will most likely make things much easier for me