exact distance between centers

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NY Sculptor
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exact distance between centers

Post by NY Sculptor »

I hope somebody has the answer to this!
I have to drill holes in an aluminum sheet at very precise distances (within .002") and have been having no luck with V-Carve Pro. I need to insert bearings into these holes, and then insert shafts which will insert into thick brass gears. If the gears are more than 0.004" too far apart, the teeth won't mesh and the gears will slip. If the holes are 0.004 too close, the teeth on the gears will bind and not be able to turn.
I am not drawing all the holes in a straight line or an array, they are being placed at various points on a sheet of 3/8" thick aluminum.
Each gear has a precise pitch diameter, which tells the exact distance it must be placed from it's mating gear.
So the question is, how do I draw circles with an exact distance between one center point (vortex) and another, different sized circle's center point - with extreme precision? And from the 2nd gear's counterpoint I then have to find the placement for the next gear, and so on.
Thanks everyone!
Andrea

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mtylerfl
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Re: exact distance between centers

Post by mtylerfl »

Hi,

You can enter the exact XY coordinates for any item you want, at the time you create them, or you can use the Transform (move) features to enter exact coordinates.
Michael Tyler

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FixitMike
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Re: exact distance between centers

Post by FixitMike »

If this is for the bearings for two mating gears: Draw a circle whose diameter is equal to sum of the pitch diameter of the two gears centered on the first hole. . Draw a line from the center of the hole that crosses the new circle where you want the second hole. This will locate it precisely. Place the second hole on the intersection. (This is not the only way, but is an easy one.)

Use F4 to set snapping to help put the centers where want them.
..
Incidentally, gears can be more than .004" farther apart than the ideal center distance without a problem unless they are quite small.

I spent more than 35 years designing gears and machinery that used them. PM me if you need more information.
Good judgement comes from experience.
Experience comes from bad judgement.

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