My X and Y is off by .2 width of edge finder

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Nigelo
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Re: My X and Y is off by .2 width of edge finder

Post by Nigelo »

I don't use Clearpath servos so I may be a million miles away. Are you sure the Clearpath Input Resolution is correctly set to 6400 thereby matching your Acorn settings?
Hope this helps
Nigel

"You can lead a horse to water but you cannot force it to drink"
cnctreker
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Re: My X and Y is off by .2 width of edge finder

Post by cnctreker »

Yes, Clearpath is built in to the Wizard. Just select and load.
ShawnM
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Re: My X and Y is off by .2 width of edge finder

Post by ShawnM »

Nigelo is talking about the settings in the motor itself that are set with the MSP Software. Selecting Clearpath in the wizard does not set up the motor. But everything else is working right so I'd assume that the motors are set for 6400 by default as well.
cnctreker
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Re: My X and Y is off by .2 width of edge finder

Post by cnctreker »

Everything is working mechanically since I can tell either x or y to go to any coordinate with high degree of accuracy. Just when you go to x0, y0 it fall short of by .2 (diameter of the edge finder). The work around is modify WCS G54 so basically I can't use the edge finder.
cncsnw
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Re: My X and Y is off by .2 width of edge finder

Post by cncsnw »

On the Part Setup screen, there are three things you need to tell CNC12 before it can set the correct WCS position.
1) "Part position" = what coordinate value you would want the DRO to have, if the spindle center were over the edge you are touching
2) "Edge Finder Diameter" = the diameter of the edge finder or tool you are using to touch that edge
3) "Approach From" = from which side of the part you are coming, when you move the edge finder towards the edge.

In the screen pictures you posted on Saturday, you cut off the "Approach From" column. That suggests that you do not fully recognize its importance.

If you are setting the X axis part location; and you want to make the edge be at X0; and you are using a 0.200" edge finder; and you are moving that edge finder towards the part from the X- side (that is, you are jogging X+ until it trips), then you would enter:
1) Part Position = 0.000
2) Edge Finder Diameter = 0.200
3) Approach From = Left (-)
... then you would jog slowly X+ until the edge finder trips; then press F10/Set. The DRO would then show "X-0.1000", because at that moment, the spindle centerline is 0.100" to the minus side of the new X0 position.

It is possible that some of the confusion stems from translating "left" and "right" into positive and negative movement.

On all CNC vertical mills, from the usual viewing position, cutter movement from left to right is X+; and cutter movement from right to left is X-.

On many CNC vertical mills -- e.g. most knee mills, bed mills and machining centers -- X axis movement is achieved by moving the table and workpiece beneath the cutter. To make the cutter move left to right through the workpiece (X+), the control system moves the table to the left, while the cutter stays in place. That does not change the fact that left-to-right cutter movement is X+.

It is also possible that the confusion is over whether "Approach From" means "we are approaching the part from this side", or whether it means "we are moving in this direction to approach the part". "Approach From" means "we are approaching the part from this side. It is, therefore, opposite the direction you are moving to approach the part.
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