Author Topic: Bit Height Offset  (Read 4051 times)

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Offline CanAm1

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Bit Height Offset
« on: August 14, 2011, 08:35:41 AM »
Hello All,

The newbie once again has a question for all you pros out there.
In setting up the bit height I use a .375 inch roller bearing. I will jog Z up and down until the bearing will just roll under the bit with a very slight amount of resistance and then zero out the axis followed by adding .375 to the DRO. This may not be the best way of setting the bit height, but I have been getting pretty good results.
My question: If and how would one put this .375 measurement into Mach3 to where when I am setting up my bit height all I have to do is zero the Z DRO and the program automatically adds the .375?
I hope I explained this correctly.

Thanks

Mark

Online ger21

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Re: Bit Height Offset
« Reply #1 on: August 14, 2011, 08:53:50 AM »
Upper left corner of the offsets page. Enter .375 in the gauge block height, and click Set Z to set your Z zero position at .375.
Gerry

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Offline CanAm1

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Re: Bit Height Offset
« Reply #2 on: August 14, 2011, 09:19:29 AM »
Thanks Gerry.
That works, but is there a way to have Mach add the .375 when I hit the zero button?
In other words, when I am setting my bit height and I get it where I want it to be all I have to do is zero the Z and Mach3 will zero Z and add .375.
I may have to have some sort of macro to do this.
I am trying to get things setup to where I don't have to fiddle with the keyboard and can just do things from my new pendant.

Mark

Offline HimyKabibble

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Re: Bit Height Offset
« Reply #3 on: August 14, 2011, 09:27:13 AM »
It is FAR easier to use probing to set the Z position.  Unless you have a tool changer, using tool length offsets really doesn't buy you much....

Regards,
Ray L.
Regards,
Ray L.

Offline Hood

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Re: Bit Height Offset
« Reply #4 on: August 14, 2011, 09:45:30 AM »
If your pendant has configurable buttons that can trigger macros then yes it would be simple enough to have the macro set the Z DRO to the value you wish.

Hood

Offline CanAm1

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Re: Bit Height Offset
« Reply #5 on: August 14, 2011, 10:31:46 AM »
Hood.

The pendant has 2 spots for macros.
I guess I'll start reading up on them.

Thanks

Mark

Offline BR549

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Re: Bit Height Offset
« Reply #6 on: August 14, 2011, 01:06:39 PM »
Here is the code that is in the button on the offsets page that does your function. It should be a good example to help get you started on macros.

Code "G92.2"
Call SetDRO(2, Abs(GetOEMDRO(1001)))

Hope that helps, (;-) TP

Offline Hood

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Re: Bit Height Offset
« Reply #7 on: August 14, 2011, 03:17:59 PM »
Or if you will always use the same height gauge then just replace the last part with that height
Example is with your 0.375 above

SetDRO(2,0.375)

One other thing that may be worth mentioning is its better to move the cutter lower than the gauge then jog up in increments until you can slide it under. Doing it that way avoids the chance of moving too much onto the gauge and damaging the cutter, especially if its carbide.

Hood

Offline CanAm1

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Re: Bit Height Offset
« Reply #8 on: August 17, 2011, 12:40:38 PM »
Hello All,

Thanks for the additional comments.
I have done some experimenting with Klaus’ Screen Designer as the original Mach3 Screen Designer comes up slightly scrambled on my computer. Yes, I am using a copy of my screen set and have come up with a couple of solutions that work for my needs.
I was trying to get the functions that I typically use to run the CNC setup on my pendant to keep from playing contortionist in reaching my keyboard.
My pendant has two “GOTO” positions on it that were not working. One was Tool Change Position and the other was Safe Z Position.
First, I added another button to the Tool Information Block on screen 1 and labeled it “Tool Change Position” to replace the button that disappeared during revisions.
Second, I discovered that the Auto Tool Zero button in the same area currently is not being used as you get a “Yet to be implemented” message if you click on it. I relabeled it to read “Zero Z +.375” as I don’t feel I need a safe Z function.
Next I played around with the button defining blocks for these two keys. I used Hood’s (thank you) script for the Zero key and it works. I can click on it with the mouse or use my pendant to get that function to perform. I still need to tinker with the script for the tool change key to get it up and working.
Not too bad for an old fart Huh???

One question I do have is that when I was defining the keys in the screen designer I noticed that at the top of the defining block there was a Global yes/no selection. I figured this may mean that the function of the key could be allowed to occur no matter what screen you were on. Well, I clicked yes and things really went strange on me. The button wound up with a red line around it and the defining block changed to 3 lines with all my scripting and labeling vanishing. What gives with this happening??

Thanks everyone.

Mark

Offline Hood

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Re: Bit Height Offset
« Reply #9 on: August 17, 2011, 01:14:48 PM »
Sorry cant help with MachScreen as I dont use it, I use Screen4. I am sure someone will be along to help, if not give Klaus a shout as he is always very helpful.
Hood