duel y motor setup help please

(All sorted , setting up the homing on all axis is key , my z was not configured )



Help please  
i have a very basic knowledge of all of this ( and a little slow, if you know what i mean ) 

i have just updated my linuxcnc to debian 10 and axis to 2.9 (Master i think ) , i would like to make use of gantry auto squaring so i setup each y stepper seperatly using y and tandem y pins , 
 im pretty confident i have wired all up correctly , (I disconected the motor couplings to test so all is safe ) when i jog the y axis ( down arrow on keyboard ) only the y motor runs , when i jog the z axis via keyboard the tandem y motor runs , if i jog y via the axix screen and mouse only the y motor runs , if i jog the z axix via the axis screen the z axis moves but only 0.001mm at a time ( edit , this is fixed now , i had my travel limit set incorrectly , now z jogs fine via mouse on axis)
can anyone off some advise please as to where i can look to solve this problem 

and then also to clarify , it seems when i make a change in stepconfig the ini and hal files seem to not be overwritten but rather a copy with a number prefix , is this normal ? , 2.8 used to just overwrite , its convenient now as mistakes are not lost but it can get messy , can i just delete the old files once im happy with any changes i may have made ?

ive attached my ini and hal file if you are able to take a look to help dignose my problem 

Jogging behaviour is different before and after homing. For tandem axes you should really have a HOME_SEQUENCE entry with a negative number to indicate the joints are synchronised, this will prevent jogging before homing for those joints. See the Homing section in the link.

linuxcnc.org/docs/devel/html/config/ini-...t__lt_num_gt_section 

great thank you , i will go take a read , hopefully my answer lies there

The machine needs to be homed before the jogging works

This is an extract from my ini file

STEP_SCALE = -29 ( -ve number was used to reverse the motor direction instead of changing the motor connections)

# final home position macine-unit/sec
HOME = -20

# use this to square the gantry
HOME_OFFSET = 0.05 ( this sets the offset to square the gantry )

# machine-units per sec next 2 lines
HOME_SEARCH_VEL = 50
HOME_LATCH_VEL = -2 (the -ve number is to make it back off the switch)
HOME_FINAL_VEL = 50

HOME_USE_INDEX = NO
HOME_IGNORE_LIMITS = YES
HOME_SEQUENCE = -2 (this needs a -ve number the same in both tandem joints)

excelent , thank you
so if i park my gantry in the middle of the table and power off , when i restart the next day i have to home all the way back before i can jog ?
i usally park at the far end , gives me a table to work on when im not using the router

cabeng wrote:

excelent , thank you
so if i park my gantry in the middle of the table and power off , when i restart the next day i have to home all the way back before i can jog ?
i usally park at the far end , gives me a table to work on when im not using the router

Yes but that takes seconds to do.

i need to increase my homing speed , its a crawl at the moment

thank you very much , i have it all working now , setting up the homing was the key

how setting first time my dual Y axis at setup wizard, i has try add my parallerport pin 8 and 9 is A axis, and setting pins 8,9 to tandem Y step and dir, normal Y have pin 4 Y step and 5 is Y dir, but no working. what i need setting can use 2 motor Y axis. new version 2.9.4 old has 2.8.4.

how setup dual Y axis, just installed new version linuxcnc because i hear support dual Y axis motors, but now first time try setting wizard make tandem Y step ad dir add to pin 8 and 9 (A axis in card) no working.

If starting fresh using the Stepconfig wizard in 2.9, don't use the "A axis" settings to configure your secondary Y axis joint. Start by configuring your machine as a XYZ machine, then choose "Tandem Y Step" and "Tandem Y Direction" for the step/dir output pins for the secondary axis on your parallel port. Similarly you must configure a separate home switch for both Y motors using two input pins connected to "Home Y" and "Home Tandem Y" (or one of the available combined home limit options available with those pin input options.)

If you already had a functioning configuration with version 2.8, you should be able to import the configuration files from that and have them work with 2.9 without needing to make any significant changes. (Maybe I think.)