Small mill Axis configuration

I have a real little mill the table size is 5.5 inches by 5.5 inches. Its mission is to mill PCB's. I am having a time trying to figure out what I need to enter into the Stepconf Wizard for the various Axis settings.
I am using a Gecko G540 step motor driver with 10 TPI acme single start thread screws. The spindle is a cnconabudget.com 3 speed PCB spindle Currently using inches for measurement.

The mill is like a Vertical mill with the Z Axis stationary except for up and down movement.
LinuxCNC 2.6.1 and Debian is what I have loaded.

Z axis travel is 3 inches
X Axis travel 7 inches but there is a bearing block in the center and table support, that is 2.5 inches long supports the table so I guess I would subtract that from the table travel length?
Y Axis is 9 inches travel

Home position currently is -Y ; +X and +Z. With Y being fully forward, X is fully right and Z is all the way up. I do have homing switches installed but need to do some adjustment work on them too so until I get the mill moving about they are disconnected

What value do I enter into the Table Travel field, the travel lengths I physical measured for each Axis? I have seen some configurations that suggest entering -1000 to 1000
With the set up I currently have the Axis travel except for the Z which moves only about 1/8 inch for each press of either the - or + buttons in the AXIS screen. I am sure it is a configuration issue as the Axis moves fine under test axis in StepConf screen.

I have read the set up guide but I apparently am not catching on to what it is saying. Not worried about any fine tweeks yet, just want to get the thing moving about and maybe have to draw some thing on MDF

Thanks for any advice you can provide

Gary Fiber K8IZ

the easy answer is to attach your hal and ini files , that way we can check your configuration and calculations

Here are my .hal and .ini files. These were generated by by StepConf and I have not made any changes to then yet. Seems all of the example files are to big for my mill as reported by various movement errors exceed limits of the axis travel on my mill, not surprised though as it is so small.
Though the Z Axis still only moves just maybe 1/4 inch before stopping when I press the - or + in AXIS screen. The X & Y axis move fine when pressing the -or+ buttons.

Even Peter Smid's CNC Handbook has not been much help, was hoping it would tell me what to look for in axis travel measurements, but I am sure it will be when I get into G-code modifications..

A few pointers to get me started will be helpful, I am sure its not as hard as its turning out to be, seems the trees are blocking the forest.

Gary Fiber K8IZ

Everything is based on where machine origin (zero) is on the axis.
Decide where machine origin will be on an axis. it can be anywhere inside the limits eg if the spindle moves up and down max z+ is usual

from machine origin, the distance the axis can move in either direction is the table travels.
eg with the last example +0 -10 for a ten inch travel machine
if we decided the origin would be in the middle of travel then the table travel mould have been -5 and +5

in actuality the table travels define where the limit switches are and stepconf sets the axis limits just barely inside them.

the home switch is defined from the origin too.
so for out first example to use the Z+ switch set home offset as zero (cause that's how far from the origin it is)
or to use z- set home offset as -10 (-10 inches away from the origin)
if you have a separate home switch you can set it anywhere in between. (0 to -10)

if you fire up pncconf and click the help button look at the diagram - let me know if that helps I could add it to the new stepconf

Chris M

Chris has given a few pointers , see how you get on , but shout if your stuck ,if you have skype give me a call and we could work through
and problems etc , but be aware i'm in the UK .

to set up the tpi you will need to know the gecko's default microstep value
most of what you need can be done in stepconf

Chris and cncbasher...

Thanks for the help and assistance offers !
I've been away from the little machine for a few days and hope to get back at it this weekend. I did print out my .ini and .hal files and have been looking them over to see if I can find the mistakes in the setup.

Gary K8IZ

here's a few configs for the geko
so take a look and anything your not sure of shout and we can give guidance etc

Dave
G0JQO