Axis setup

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lvanduyn
Posts: 62
Joined: Tue Jan 30, 2018 2:26 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: E8EB112A1F04-0206180612
DC3IOB: No
CNC11: No
CPU10 or CPU7: No
Location: Alamogordo NM

Axis setup

Post by lvanduyn »

I received my Acorn and NUC yesterday and all is connected on the bench and
running the bench test nicely. In looking at the axis configuration in the wizard,
I note that it wants steps/rev and overall turns ratio. My router uses belt drive
for the X and Y axes and a ball screw for the Z. Coming from the mach 3 world,
all the calculations are in steps/inch. X is 2142.408 step/inch. Y is 3079.141 step/inch.
The Z axis has a 4mm ball screw . How do I get from steps/inch to what the wizard wants ?
Larry
Gary Campbell
Posts: 2164
Joined: Sat Nov 18, 2017 2:32 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: Acorn 238
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Marquette, MI
Contact:

Re: Axis setup

Post by Gary Campbell »

Larry..
Easy way would be if you know your current steps per inch and Drive microstep settings.

For example: 2142.408 / 1600 = 1.339005 revs per inch (drive set at 1/8 microsteps)

Hows that?
GCnC Control
CNC Control & Retrofits
https://www.youtube.com/user/Islaww1/videos
lvanduyn
Posts: 62
Joined: Tue Jan 30, 2018 2:26 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: E8EB112A1F04-0206180612
DC3IOB: No
CNC11: No
CPU10 or CPU7: No
Location: Alamogordo NM

Re: Axis setup

Post by lvanduyn »

Hi Gary
Thanks for the reply. I posted before thinking the thing all the way through. My bad.
The X and Y axes are timing belt driven and have two stages of pulley reduction from motor to the final drive pulley.
The encoder is on the intermediate pulley. The inch per rev of the final drive pulley is known and the pulley ratios
are known so it becomes inch/rev/drive pulley times reduction ratio divided by encoder lines. This should
get me close enough to tweak it in by measurement when I get it all together.
Larry
Gary Campbell
Posts: 2164
Joined: Sat Nov 18, 2017 2:32 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: Acorn 238
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Marquette, MI
Contact:

Re: Axis setup

Post by Gary Campbell »

You may have to forego the encoder inputs with the acorn, unless they interface with your drives.

For the ballscrew the setting would be 1mm = 0.03937 * 4 = 0.15748 inches per rev
GCnC Control
CNC Control & Retrofits
https://www.youtube.com/user/Islaww1/videos
lvanduyn
Posts: 62
Joined: Tue Jan 30, 2018 2:26 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: E8EB112A1F04-0206180612
DC3IOB: No
CNC11: No
CPU10 or CPU7: No
Location: Alamogordo NM

Re: Axis setup

Post by lvanduyn »

I am using GECKO 320 servo amps and the encoders go back to the drives.
On the 4 mm Z axis, I overdrive the screw by a 30/22 ratio to speed things up a bit.
The motor has a 2000 count encoder.
Any progress on your 4th axis ?
Larry
Gary Campbell
Posts: 2164
Joined: Sat Nov 18, 2017 2:32 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: Acorn 238
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Marquette, MI
Contact:

Re: Axis setup

Post by Gary Campbell »

Larry...
The only progress is that I have received notice that the parts have shipped, hopefully next week they will be here
GCnC Control
CNC Control & Retrofits
https://www.youtube.com/user/Islaww1/videos
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