【转帖】chamfer call ou

yang686526

chamfer call out
when using a leader to call out a chamfer (ie. .040 x 30) to my knowledge the .040 be the depth into the material and the 30 degrees is the angle from the centerline. is this correct or do i have it backwards?
the .40 is the distance from the edge and the 30 degrees is the angle starting at the .40 location.
it is not a good idea to dimension such a chamfer with a leader callout, as the angle is indeterminate.  it may result in a 60 degree or a 30 degree chamfer, depending which surface the machinist chooses to apply the dimension to.  such a feature is shown with a linear dimension and an angular dimension, or two linear dimensions.
the leader is how the owner wants it done, but i agree with you.  now to convince him that this is the proper way.
thanks!!
i agree with ewh.
but, if it's a 45 deg chamf, then the callout is ok. otherwise, i suggest dim the angle and depth.
chris
systems analyst, i.s.
solidworks 06 4.1/pdmworks 06
autocad 06
i do not have a copy of the actual standard on my desk but i am looking at "design dimensioning and tolerancing" by bruce a. wilson asme senior which is based on the asme y14.5m-1994 standard. on page 71 it says,
"chamfers of 45deg can be dimensioned by note. all other chamfers angles must be dimensioned in one of two ways. one way is to show the angle of inclination and the length of one side of the chamfer. the other way is to show the length of both sides of the chamfer.
a note can be used for 45deg chamfers since both sides of a 45deg triangle are equal in length. the sides of any other angle are unequal and therefore can't be specified by a note. a note can't specify which side of the angle is being given. the only way to be certain of control over chamfers other than 45deg is to apply the chamfer dimesions to the part."
again, i don't have the exact standard referance but maybe someone else can find it for you.
asme y14.5-1994 para 1.8.15 and 1.8.15.1 pretty much state what aardvarkdw posts above.
i knew it was there somewhere, i didn't have the spec here to look up.
thanks aardvarkdw & ewh.
chris
systems analyst, i.s.
solidworks 06 4.1/pdmworks 06
autocad 06
thanks ewh, i was hoping someone could back me up.