hexagon logo

Bad parallelism and good thickness, what can be common...

Hi all.
Situation: I have a round thin part, and on each side I measure 6 points on 3 radii exactly opposite each other. Next, I measure the thickness of this part between them. As well as its flatness and parallelism between the planes built from these points.
Please help me understand how this can happen and why. I understand the difference between flatness and parallelism, but here I can’t explain why, with such an even thickness over the entire surface of the parts, we have such poor parallelism. I would be very grateful if this was depicted visually, so that the explanation would be just for dummies.

Parents Reply
  • Indeed. Form tolerances must be smaller than gd&t characteristics that depend on them. Otherwise you don't know what is really out. Once again likely another bummer from an MBA engineer who was dozing during that one semester long gd&t class while taking 5 humanities classes instead. Apparently engineering bosses thought engineers are better when versed well in poetry and not so in gd&t.
Children
No Data