[WarrenW]

I'm getting ready to start building my first cnc router and have a question about the travel distance for the Z axis. Is there a standard amount it should be set at? All I plan to use this machine for is cutting shapes in 1/8 inch birch wood. So I do not need as much travel in it as others.

The reason I ask is if I can build the gantry to be not as tall even by a few inches, won't that take away any chance of it swaying? And once its built, do I do some sort of calibration in the setup of the software to tell it how far each axis will move and its limits?

Off to HomeDepot!

I have the following so far:

1/2-10 acme threaded rods
AB nuts ordered from Dumpster on here
Xylotex 3 axis driver board
Nemo 23 269 oz/inch motors (3 of them)
Power supply / fax from Xylotex
1" drill rod
Roller bearings

I plan to build it very similar to JGRO's design but will extend the X axis some and support the linear shafts on each side to reduce any flexing. I will be posting a log with pics on here as I build it.

Thanks!

Warren

[ger21]

You need to allow for whatever different size tools you'll be using, how the router mounts, and the material thickness. If you're just cutting 1/8", you could get away with as little as 1". I'd shoot for 2-3". You might find a lot more things you'd like to do when you get it working.

[SIGMA7]

help! please. how i can make short ascend and descend for z axis on mach 3. the DRO for z axis say +60.0000 when is on top and +0.000 when is down to material. normally +0.0000 is the top of the work piece, but from +60.0000 to +0.0000 is a long travel. i already see some videos on the web for cnc machines with short ascend and descend on his z axis. please help!!!.

[Kipper]

Not sure what you're asking Sigma....How to Zero the DRO? or maybe how to calibrate the axis?

Some inference may be lost in translation :cheers:

[CarveOne]

help! please. how i can make short ascend and descend for z axis on mach 3. the DRO for z axis say +60.0000 when is on top and +0.000 when is down to material. normally +0.0000 is the top of the work piece, but from +60.0000 to +0.0000 is a long travel. i already see some videos on the web for cnc machines with short ascend and descend on his z axis. please help!!!.

On the ALT-6 tab screen right above the Reset button is an axis calibration utility. Click on that and follow the instructions. It will ask you a distance to travel, then you confirm that it moved the distance that you requested. The utility will automatically calculate the proper numbers to put in the motor tuning settings. That should correct your problem.

CarveOne

[SIGMA7]

THANKS! for the answers. but i mean when i open a g-code on mach 3 the z axis move to +60.000 on the top, and move down to +0.000 that's is ok but +60.000 is the probelm from +60.000 to +0.000 take time in the ascend and descend movement, i want to make short ascend, this is not speed setting related. if you get too much speed to the motor it will lose step synchrony and sudden stops . something like +40.000 is ok, i'm starting to think the problem is on the g-code i must edit the g-code i think.

[Kipper]

THANKS! for the answers. but i mean when i open a g-code on mach 3 the z axis move to +60.000 on the top, and move down to +0.000 that's is ok but +60.000 is the probelm from +60.000 to +0.000 take time in the ascend and descend movement, i want to make short ascend, this is not speed setting related. if you get too much speed to the motor it will lose step synchrony and sudden stops . something like +40.000 is ok, i'm starting to think the problem is on the g-code i must edit the g-code i think.

Set a nominal value for clearance...I usually set 1mm for clearance moves....Maybe notepad++ or Crimson editor can help to edit the files...Ie search and replace all the big Z+ moves?

hth

[ger21]

Do you have Safe Z set at 60? If not, it's probably your g-code.

[SIGMA7]

hello!. thanks for your help.
i manage change the huge +60.000 values on gcode for z axis, i found that you can put any values for any axis and you can say to all axis go to specific position after of work is done. i already learned many things on mach 3, now i can complete the the tests for athc, analog torch height control, i want to say, thanks for the help and support!!!!!.
news on athc coming soon stay tuned!!