Probing a part question

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Black Forest
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Probing a part question

Post by Black Forest »

I have built a power drawbar for my mill. The plate on top of the mill that the power drawbar will mount to has a 60mm diameter boss in the middle with a four bolt hole circle approximately 80mm radius. What would be the procedure for using my probe to measure the bolt hole circle? The four holes are 6mm in diameter not threaded. My plan is to just use longer bolts and bolt through the bottom plate of the power drawbar and this top plate on the spindle into the head. I can do it with calipers and get it usable but I was wondering how to do it more accurately using the probe. I only have the pro license for the mill. In the picture you can see the gray bottom plate with the boss on the top plate of the spindle sticking through it. I don't know why the picture got rotated. Sorry.
power draw bar.jpg
suntravel
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Re: Probing a part question

Post by suntravel »

If the BHC should be in the middle of the workpiece and It is round, use boss to find center with the prob app.

Intercon Drill / DrillBHC Position X Y = 0

Start drilling

Uwe
Black Forest
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Re: Probing a part question

Post by Black Forest »

How would you accurately find the radius of the BHC? Finding the center off the boss no problem.
Black Forest
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Re: Probing a part question

Post by Black Forest »

The way I did it was to put the plate from the spindle top on my mill table and align two for the opposite holes along the X axis using my 3D taster. Then I put the tip of the 3D taster in one hole on the side closest to the center boss and zeroed my X axis. Then I went to the opposite hole and measured the inside closest to the center boss. Took that measurement from the X axis readout and divided by 2 and added 6 to get the center of the 6mm holes. That gave me the radius to use in Intercon to make the bolt hole circle. I wanted to know if there was a way to do this with my probe somehow that was a little more sexy!
suntravel
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Re: Probing a part question

Post by suntravel »

Ah ok.

One way is to clamp the piece with two holes aligned to one axis on the mill.

Find center of one hole, set XY 0, find center of the other hole and the distance is the BHC Diameter

Or clamp not aligned and calculate with trigonometric math.

But I simple measure one hole with the digital caliper, set it to 0 and measure the distance from the outside of two opposite holes.
Shows the diameter without calculating in 10s.

Uwe
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Re: Probing a part question

Post by Black Forest »

OK. Got it. Thanks.
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