z zero

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pabneypaol
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z zero

Post by pabneypaol »

Using Mach 3, I like to zero my z to the top of the material for anything that does not cut all the way through the material, but for any tool path that does cut through the material, I like to z to the table. This way I do not need to know the exact thickness of the piece I am cutting and I can still leave an onion skin on the through cuts. I am probably making this a lot harder than I need to.

In a nut shell, Is there a better way? (I know there must be, just can not seem to figure it out)

Thanks
Paul
Knowledge is knowing a tomato is a fruit, wisdom is knowing not to use it in a fruit salad.

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Adrian
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Re: z zero

Post by Adrian »

That's exactly what I do on my ShopBot. For through cuts zero to the table. For VCarving and other "top down" cuts I zero to the top.

I know most people always zero to the top OR the bottom but I prefer this way.

I've modified my post processor so the files give me a warning so I don't get the zero point mixed up. It also warns me about orientation of the piece and where the origin is. Made that mistake one too many times. ;)

pabneypaol
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Re: z zero

Post by pabneypaol »

Adrian,
I would love to know about your post processor edits. Maybe I could do the same to the mach 3 PP. I currently use a touch plate to set the z zero using a macro. I think mach has an offset function. What I would like to do is always set the z to the table. Then using another macro put the zero plate on top of the material and offset to that. Or maybe do it all in one macro. Here is the way I envision it.

Place material on table and clamp
z zero to top of table
move over material and offset to top (for top carving)
stay on the table and offset for bottom cutting

Not sure if this is feasible or not. But that way all my files can be set up to table zero, and I would not have to switch back and forth.

Paul
Knowledge is knowing a tomato is a fruit, wisdom is knowing not to use it in a fruit salad.

ger21
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Re: z zero

Post by ger21 »

My Mach3 2010 Screenset allows me to enter the material thickness and zero off the table. So I can just type in where I want my zero to be, and still leave my plate on the table.

Typically, if I'm cutting ±.75" parts, I'll cut to .74 or .745, and set my zero .75 off the table. It then doesn't matter how thick the material actually is.

For V-Carving, I can disable the offset and zero to the top of the material.

It also automatically zeroes tools after a toolchange.

Theres a link on the Mach3 screen downloads page.
http://www.machsupport.com/screens.php
Gerry - http://www.thecncwoodworker.com

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Adrian
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Re: z zero

Post by Adrian »

pabneypaol wrote:Adrian,
I would love to know about your post processor edits.
Sorry, I missed this post for some reason.

I don't think my modified ShopBot PP would help you much. The process of setting the Z-Zero level itself is a file within the ShopBot control software itself which would be quite a bit different to how it would work in Mach3.

In my PP I've used the Vectric labels for where the Z level is, width of material etc along with the ShopBot program code to popup a window when the the file is run to tell my whether Z should be at the top or bottom of the piece, which way it should be orientated on the table and where the origin point is. 99 times out of 100 I know anyway but it's a last minute sanity check.

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