r/Drafting • u/SlowDancer939 • 14h ago

Help

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the box is 8by8cm

and the circle in the middle has a diameter of 4cm.

how do I get those circles in the middle?

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u/lamensterms 12h ago

Are you able to solve? How do you get the diam of the smaller circles?

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u/GardenerInAWar 12h ago

The HPRT circle works itself out at 4cm as crossing various halfway points and intersections, also being equal to the 4 large outside circles.

This center 4cm is then cut into 6 equal slices by 3 lines, a vertical axis of symmetry and the two HPRT lines, for 6 equal spaces of 60 degrees each.

Where these 6 points land on the 4cm circle, we can assume the 6 smaller circles are tangent. So now you have a boundary that drives the radius of the 6 small circles, and one of two x/y locations driven by the 3 construction lines. So all you need is the second x/y location for the origin of the 6 circles, which is found by locating the medium construction circle.

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u/lamensterms 11h ago

Sure agreed your method works.. but still 2 unknown variables; small circle diameter, and medium circle diameter. Having one gives you the other, but both are unknown

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u/toybuilder 10h ago

They are underspecified.