Start by identifying the contacts that establish the required drawing datums. A map distinguishing them from supports and clamps will help interpret your rocking samples.
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Fairino FR10: Some bench samples rock in our locating nest
NadiaBarnes0552 · 2026年8月28日 09:16 UTC
21 条回复
@LeahBrown0930 On my sketch, the mounting holes and outside wall both determine lateral position. Everything is labelled as a locator, with no stated priority between those contacts.
20分Take that overlap to your fixture designer with the hole-to-wall tolerances. Relieving the wall contact looks like a candidate worth reviewing.
11分@LeahBrown0930 You don't know which datum must win yet. Relieving the wall could remove the reference the operation actually needs.
21分I got ahead of the drawing requirement there. Establish the necessary datum scheme before deciding which secondary contact can be changed to accommodate permitted variation.
2分@LeahBrown0930 I'll have the designer mark that explicitly. I'm not modifying the nest from a nominal CAD view and a hunch.
5分@LeahBrown0930 I'm lost on support versus locator. Aren't both just touching the part?
4分The distinction is their purpose: a locator establishes position, while a support carries load without demanding an incompatible position. The contact design must make those purposes compatible.
18分On my fixture, we called every contact a support until the tolerance sketch showed two of them steering the same direction. The names hadn't helped.
14分@AnilBell0636 Did your review start with measurements of the poor-fitting samples? We've tended to set ours aside, and I suspect they may be particularly informative.
3分Keep them identified and compare them with the drawing. A sample fitting badly in your nest doesn't, by itself, make the sample wrong.
24分@AnilBell0636 Our inspection sheets show the awkward samples are within drawing limits. Their hole-to-wall dimensions differ within that allowance. So rejecting them would need another reason.
5分Those acceptable dimensional variations belong in the fixture requirements. A design based only on nominal geometry hasn't shown that it accommodates the permitted parts.
25分Request a sketch tracing how permitted variation is accommodated. That gives you something more concrete to review than a general assurance about sufficient clearance.
13分@LeahBrown0930 Could you just add clearance everywhere and let the clamp hold it?
14分@KaiCarter0976 You still need a repeatable datum location. General looseness may remove the conflict while losing the position your operation needs.
9分I see that increasing the clamp force doesn't define the intended position. How can I explain that constructively to the person who proposed it?
13分Frame it around the condition the clamp must retain: ask where the part should be located first, then how clamping maintains that position under the process loads.
19分@LeahBrown0930 In my separate review, drawing the intended located condition helped. It turned a vague argument about clamp strength into a discussion of the position being retained.
18分My next step is clear: get the required datums established and review how the nest accommodates acceptable variation. The planning question is answered, while a fixture revision still depends on the designer's assessment.
14分