Andy's knee mill project

Hi all,

thought i would start a thread where i can ask away about the sticking points i am sure i will encounter in the coming weeks/months...

So i have a knee mill, similar to a typical bridgeport its a Diamond...

I have purchased some C5 ballscrews for X + Y and am waiting on the quote for the required machining.

I am waiting for delivery on my stepper motors + drivers and all things CNC

I also got a bit spend happy and have a pile of tooling ready to go


so first question relates to first menu in the stepper config

I have entered values for the following based on the picture in my stepper driver data sheet. but not having had to do such a thing before i would be most appreciative if someone could have a look at how i went

Step Time How long the step pulse is "on" in nano seconds.
Step Space Minimum time between step pulses in nano seconds.
Direction Hold How long the direction pin is held after a change of direction in nano seconds.
Direction Setup How long before a direction change after the last step pulse in nano seconds

so this is screen shot from the data sheet

and these are the values as best i could work out


couldn't work out how to put 2 images in 1 post...

BigJohnT wrote:

Looks ok to me...

JT

ok. thanks need the machine running now so i can test for velocity and acceleration. any tips on doing this? / starting values? I have 12Nm stepper motors...

just got the quote in for the machining of the ball screws. will try to drop them off thisarvo...

BigJohnT wrote:

Start with low values. There is some info here on testing steppers

www.linuxcnc.org/docview/html//common_St...iagnostics.html#r1_3

John

cheers.

hopefully my steppers aren't too far away now that the ash has settled (bit of hold up on freight out of uk...)

Well it has been a while, i have a full time job now which has meant i have the money to finish but not the time:dry:

anyway i have completed the wiring with my system, same as listed here www.mycncuk.com/forums/showthread.php/19...-Wiring-Basic-Wiring

I have powered the system up, steppers are energized but i cant make them operate in the test axis part of stepconfig

"the resistors are not needed in your case.
your have a choice of either:

Active high
Connect the PLS+ to the Step X and the PLS- to GND
and the Dir+ to Dir X and Dir- to gnd.

Or Active low.


Connect 5V to the PLS+ and the PLS- to the STep X and so on."

this is a quote from the supplier of the steppers + drivers + BOB.

at the moment i am thinking of 2 possible issues i need to check first

1 i have wired active high as explained above. can EMC cope with this ( I have the distribution that comes with lucid lynx download)
2 the parallel port isn't forwarded correctly in stepconfig, it has 0x378 is this correct? how can i find out? a mate with lynux experience had a look for me but was unable to conclusively determine if the 0x378 was correct.

thanks

Andrew

will put some pics up when i remember to take some, is looking nice and schmickB)

Anyone got any suggestions?

yes it does have charge pump
i read something about how to bypass in the manual, this is a weekend project so will have a crack at it over the next couple of days

thankyou for the reply