Manually move gantry

I have the new 6550-PRO and want to know if I can manually move the gantry SLOWLY to position it exactly where I want to start a project. I could do that with my old 6550 with no ill affects but the PRO seems to lock the X & Y steppers. Is there a way to unlock them or was the machine built that way so the gantry could not be moved manually??

Couple of things to keep in mind here:

Moving the older 6550 manually could have always had ill effects - as the stepper motors will generate AC voltage when they are spinning (I measured 3-4VAC just “flicking” the motor shaft with my fingers) - so you always want to take that into account. We will NEVER recommend moving the gantry manually; rather, use the jog functions to move it where you want. Since the Pro will home on startup, you can always use the starting location to define where you want the laser to start at.

The $1 configuration setting in the GRBL configuration is defaulted to a value of 255 on the 6550 Pro - this means that the motors will stay energized (or locked). Changing that value to a 0 will mean they never lock, and values between 1-254 will be the number of milliseconds before it releases.

Keep in mind this info from the GRBL config wiki - removing the idle delay can result in lost steps, so use this with caution.
#### $1 - Step idle delay, milliseconds

Every time your steppers complete a motion and come to a stop, Grbl will delay disabling the steppers by this value. OR, you can always keep your axes enabled (powered so as to hold position) by setting this value to the maximum 255 milliseconds. Again, just to repeat, you can keep all axes always enabled by setting $1=255.

The stepper idle lock time is the time length Grbl will keep the steppers locked before disabling. Depending on the system, you can set this to zero and disable it. On others, you may need 25-50 milliseconds to make sure your axes come to a complete stop before disabling. This is to help account for machine motors that do not like to be left on for long periods of time without doing something. Also, keep in mind that some stepper drivers don’t remember which micro step they stopped on, so when you re-enable, you may witness some ‘lost’ steps due to this. In this case, just keep your steppers enabled via $1=255.

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Well, that certainly answered my question! :smiley: :rofl:

Thanks for the reply. On the 6550 I used a framing square to align the work piece to the gantry. I’ll come up with a different way to square my work piece to the gantry.

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