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Midpoints in bends on a tube

Hello all. I was wondering if anyone could explain how to get some of these points in this drawing, and hopefully help in getting a dimension.

For this part, I would create a plane on the left end of the part, followed by cylinders for each straight. Then a plane on the right side. Next, I would construct a pierce point for plane 1 and cylinder 1 which would give me midpoint 1. Then construct an intersection point between cylinder 1 and 2, and that would be midpoint 2. I would continue this for the rest of the tube until i get to the last pierce point giving me midpoint 7. I have learned that i can create a cast point on cylinder 2, and it will give me midpoint 2.2; however, I have not yet been able to figure out a way of getting any of the x.1 midpoints.

That is where my question starts: How can i get these .1 midpoints? I feel like I've tried every combination of picking two cylinders and all the different types of points, and have had no luck in getting them. I have XYZ coordinates for these points, but more importantly, i have length-of-straights dimensions that are taken as a measurement between for example 1 to 2.1. This is a crucial measurement to the fit/form/function of our part, and as of now, i have absolutely no way of checking it.

My second question is this: Almost every part we have has a dimension for mid 1 to mid 7 across the Y-axis (as shown). But they will also dimension in this case, the top of cylinder 1 to the bottom of cylinder 7 (relative to the Y-axis) across the Y-axis. Every time i try to measure Cyl 1 to Cyl 2 across the Y-axis (with plus diameter getting me the closest), I never can seem to quite get a passable measurement.

Any help in either of these matters would be greatly appreciated.
Parents
  • Ok, then I understood you correctly. Don't trust the cast point unless you have clicked an autocylinder on CAD. If it's a measured cylinder you will never measure at the exact start/end, and if you don't have CAD where would you get the numbers from?

    I'm sorry that my explanation was difficult - could you specify more clearly what you don't understand?

    The red points in my picture are your intersection points 1, 2 and 3. The two green Points are your 2.1 and 2.2 points. They are the tangent points between the center lines and a nominal circle with the bend radius.

    You'll have to repeat with 2-3-4, 3-4-5, 4-5-6 and 5-6-7 to get all your Points


    It is also possible to calculate the rotation by comparing plane 1-2-3 with plane 2-3-4 and so on.
Reply
  • Ok, then I understood you correctly. Don't trust the cast point unless you have clicked an autocylinder on CAD. If it's a measured cylinder you will never measure at the exact start/end, and if you don't have CAD where would you get the numbers from?

    I'm sorry that my explanation was difficult - could you specify more clearly what you don't understand?

    The red points in my picture are your intersection points 1, 2 and 3. The two green Points are your 2.1 and 2.2 points. They are the tangent points between the center lines and a nominal circle with the bend radius.

    You'll have to repeat with 2-3-4, 3-4-5, 4-5-6 and 5-6-7 to get all your Points


    It is also possible to calculate the rotation by comparing plane 1-2-3 with plane 2-3-4 and so on.
Children
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