Lost Coordinates and how to recover from them

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The_Researcher
Posts: 7
Joined: Wed Nov 30, 2016 5:13 am

Lost Coordinates and how to recover from them

Post by The_Researcher » Thu Jul 20, 2017 5:04 am

Greetings all, I am seeking help on the following.

I have a 2 tool path cut. The first tool (60D) is successful, while i am changing the tool i move the router due to the cullet nut being to tight. I tell the carbide to go back to home, and now i see that its off by some measurement. how do i go back to the original coordinates so i can continue my second tool?

Wayne

WillAdams
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Location: Pennsylvania --- south of the Turnpike, East of US-15
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Re: Lost Coordinates and how to recover from them

Post by WillAdams » Thu Jul 20, 2017 5:36 am

Ideally you would write down the offset from the machine origin.

Are there features you can measure to determine the stock origin?
Shapeoko 3XL #0006 w/ Carbide Compact Router w/0.125″ and ¼″ Carbide 3D precision collets

The_Researcher
Posts: 7
Joined: Wed Nov 30, 2016 5:13 am

Re: Lost Coordinates and how to recover from them

Post by The_Researcher » Thu Jul 20, 2017 1:37 pm

I have been semi successful manually getting my alignment back but its never perfect. I will write down the coordinates as a work process from now on.. Thanks..
Wayne

Dan_the_Chemist
Posts: 76
Joined: Thu Nov 10, 2016 2:52 am

Re: Lost Coordinates and how to recover from them

Post by Dan_the_Chemist » Thu Jul 20, 2017 6:21 pm

Generally I have found that if I re-home the machine after each tool change the X and Y stay pretty good. The biggest challenge I've had is with the Z.

I have several places marked on my machine where I can put a 123 block to use as the height standard to set the Z for bits. By placing the block consistently and using the same portion of the block every time, I get pretty good adjustment on the Z.

If the raw material covers all of the accessible work area and I won't have an unchanging surface to place the 123 block for Z setting, then I try to cheat and pre-drilll a small blind hole in the stock which will accept a dowel pin that can be removed and replaced when needed (make sure to clean out the hole). Cleverly placed holes can look like a design element rather than a production fixture.

If none of that works I use a small steel plate, a magnetic indicator holder, and a Last Word type indicator coming in from a marked place off the work (or even off the waste board) to set the Z height.

fasteddy
Posts: 68
Joined: Sun Mar 24, 2013 10:27 pm

Re: Lost Coordinates and how to recover from them

Post by fasteddy » Fri Jul 21, 2017 1:06 am

I ran into the same issue over the winter. I was 3 hours into 3d carve when I screwed something up (don't remember exactly, but I paused the program and somehow ended losing my home.) However, after 5 minutes of utter despair, I rehomed the machine and realized that linuxcnc keeps your offsets. I had to start the program over, but I managed to save the project.

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