How to apply the right tolerances of forms for this part ?
How to apply the right tolerances of forms for this part ?
(OP)
Hi All
I would like to know the most correct way to apply the tolerances of form in this part, since it is gonna be cut in a wire cut machine. Since the part is not round, I have some doubts.
I appreciate your attention
I would like to know the most correct way to apply the tolerances of form in this part, since it is gonna be cut in a wire cut machine. Since the part is not round, I have some doubts.
I appreciate your attention





RE: How to apply the right tolerances of forms for this part ?
What is the part supposed to do?
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JHG
RE: How to apply the right tolerances of forms for this part ?
Question = don't understand and want to know
RE: How to apply the right tolerances of forms for this part ?
RE: How to apply the right tolerances of forms for this part ?
If this was my drawing, I would start it by applying datums. Good practice is for the datum features to be your mounting features. Your fabricator and inspector must be able to clamp the part using those features. I apply my tolerances and feature control frame on everything else, based on my requirements. I need to understand your fabrication processes. For example, an as-cast diameter makes a very poor feature-of-size datum.
There are all sorts of ways to fixture your part and attach dimensions and tolerances. For any given functionality, most of those ways are wrong.
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JHG
RE: How to apply the right tolerances of forms for this part ?
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: How to apply the right tolerances of forms for this part ?
RE: How to apply the right tolerances of forms for this part ?
If that's a jaw for something like a scroll chuck, it depends on the usage. We can tell you how to set up a logical datum reference frame but there's no way we could be expected to tell you how much tolerance is ok. We don't know what it's holding, what it's mounted to, what's being done to the workpiece, how accurate the next action must be, etc etc ad infinitum...
I would set Primary Datum as the mating face. I would set the hole nearer the grip-face as secondary datum and the hole to the rear as tertiary. Unless that jaw sits inside a precision slot, like a key in a keyway, the outside periphery likely doesn't matter. I assume that gripping surface at the tapered end does. But that's on you.
Profile-of-a-Surface is logical and you can either provide sufficient basic dims or a 3D model to define it.
Do the 'teeth' have to be critical or are they just there for some kind of serrated gripping improvement? If so, then I suppose the arc of the gripping face is all that matters, and your tolerance zone should be applied accordingly, leaving the 'teeth' to be constrained less.
This post has a lot of assumptions in it and my advise may be relevant or not. It's a crap shoot when you go out of your way to minimize the information you give us.
RE: How to apply the right tolerances of forms for this part ?
That's true that I might not be prefer to explain the application, but I think it has the solution : the teeth have or not have a important role. I would like to know the solution in both cases. I think that would be perfect
Also : which book has explained the composite tolerance of form well and complete?
RE: How to apply the right tolerances of forms for this part ?
RE: How to apply the right tolerances of forms for this part ?
Thank you for your both answers, no I am not willing to make it too boring
ok let's go back to your first answer, I am very sorry , but I had a hard time understanding what did you mean by the mating face, which one is it ? also how do I put a hole as a reference ? on the axis ?
shall I please if someone would sketch this for me ?
Thank you so much
RE: How to apply the right tolerances of forms for this part ?
I don't know what it is though because you have refused to expand after multiple requests for information, so I'm not going to waste time with back-and-forth discussion based on assumptions that may or may not be anywhere close to reality. Without knowing what it _IS_, we can't even communicate clearly by referring to certain features specifically by name.
RE: How to apply the right tolerances of forms for this part ?
this is the functioning