This might be a stupid question and more of sanity check, its been a long day at work, and its now almost 11 pm here, i couldn’t stop thinking about it even before going to bed lol. I understand that a CMM is the most straightford approach, for now I am hoping to find a way to check it with old school method. I was thinking to use a 1:1 overlay template with pin gages since the tolerance is pretty large. The part is a gang channel with nuts equally spaced apart. Top view looks something like this:
Looking from the front/back, it looks like this: (assume the holes are nominally centered vertically)
The true position callout is on the channel holes, the nuts are assembled to the channel with tabs, the nut have to be aligned with the channel holes or we reject them before anything else happens. The nuts minor diameter is smaller than the channel holes. (Personally, i think it’s probably better to have TP on the nuts rather than the channel holes, but anyway…)
I am thinking that since the TP of the channel hole does not change due to the nut, the virtual condition is fixed, as long as the pin through the nut does not cross the virtual condition boundary of the channel holes, the hole’s TP would be conforming. However, the true position tolerance zone in the center might not be used in this task since it could end up like this:
In this case, the blue line is the channel hole’s VC, red line is the nut, the nut is still within the boundary but the center axis would be outside of the channel hole’s positional tolerance. Which makes sense right? since the task is not asking for nut’s TP.
submitted by /u/EastWindBreaks
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