Center of material setup

Topics related to wrapped rotary machining in Aspire or VCarve Pro
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literays
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Center of material setup

Post by literays »

I have read here that many, if not all, of you set the material with Z0 being at the center of the part. How do you actually set the height of Z at the center of your 4th axis? I have a Z setter, but it is much shorter than the center of my 4th. I could create a block it sits on, but was just wondering how everyone else does it.

Thanks
Ray

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IslaWW
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Re: Center of material setup

Post by IslaWW »

Ray...
With every Z setting device there is an offset distance. In many cases for the portable type this is simply the thickness (distance from the top to bottom) of the device. In others (mostly the fixed type) the offset distance is the distance from the top of the spoilboard to the top of the device.

Which ever version you use you can set up a second macro or script and simply enter the distance from the rotary axial center to the top of the device. or look at the attached graphic from one of my rotary training slides.

In this method you verify the height of the chuck or some other fixed object, and apply a user offset from the keyboard to that height.

Hope this helps, GC
Set Rotary Z.JPG
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Rcnewcomb
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Re: Center of material setup

Post by Rcnewcomb »

On my rotary setup I knew that the top of the tailstock (TS) was exactly 0.75" from the center. I had a custom Z-zero routine that would touch the top of the tailstock and reset the Z0 to be at the center of the tailstock. That way I could change bits and re-Zero even if material was in the indexer.
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TReischl
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Re: Center of material setup

Post by TReischl »

I do a similar thing to what Randy does.

I put the touch off plate on top of my home made tailstock, the touch off routine does the calcs.

An easy way to figure out how far a tailstock or similar touch off point is from the actual center is guesstimate it within a reasonable amount.

Then cut a cylinder and measure the actual cut diameter. The difference is half of what you will need to adjust the original setting.
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literays
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Joined: Sat Oct 31, 2015 11:44 pm
Model of CNC Machine: home made

Re: Center of material setup

Post by literays »

Thanks guys.

Yesterday I did the opposite of what randy talked about. I measured from the base to the center, and then after touching off the base, it set to the center. I guess it was a brain fart moment ( for about 2 years) I just never thought of doing it that way.

Ray

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