Messages

11

General Mach Discussion / Re: lathe threading problem

« on: October 21, 2016, 11:41:16 AM »

hi all
i have looked at the index pulse signal on the diagnostics page & it will flash about 6 times straight after each other &  then it seems to miss about 3 flash's & then does the six flash's
the control board for the spindle index has an led on it that flash's with the pulses this seems to be flashing on every pulse signal
hood - i will try 0 on the debounce on sunday when i next go to my workshop , i have also tried the input in 2 diferent positions on the breakout board & still get the same results
thank you all for your replies
robert

12

General Mach Discussion / Re: lathe threading problem

« on: October 21, 2016, 01:30:01 AM »

rich
the index debouce is set to 10
i have checked the index signal with a meter , i am getting 5.08 volts working & 0.8 volts not working this at index pulse board
at the input pin connection i am getting the same voltage readings , i have also checked the parallel cable to make sure i haven't got a broken wire in the cable
if i tick the spindle speed averaging box i get threading movement but if i tick the use spindle feedback as well as the machine just hangs when it gets to the threading cycle
robert

13

General Mach Discussion / Re: lathe threading problem

« on: October 20, 2016, 02:58:19 PM »

hood
i altered my machine settings to 'spindle feedback in sync mode' when it came round to the threading cycle the machine moved to the starting position & didn't move any further
help please , have i got a corrupt version of the thread code , anybody got any idea's as to what is happening
all the best
robert

14

General Mach Discussion / Re: lathe threading problem

« on: October 19, 2016, 11:22:45 AM »

hi
thank you to rich and hood for help with trying to solve my problem , i will try both idea's tomorrow morning
when i go to my workshop
robert

15

General Mach Discussion / Re: lathe threading problem

« on: October 19, 2016, 01:27:09 AM »

rich
thank you for your reply

yes i am using stepper motors and using the parrallel port

i have checked the spindle index board with a meter and i am getting 5.08 volts when it sees the slot
and 0.8 when not seeing the slot , the disc has a single slot which is 20mm wide

the threads are done by hand coding

i always start any thread 15 mm from the front of the job
thank you
robert

16

General Mach Discussion / lathe threading problem

« on: October 18, 2016, 03:07:57 PM »

Hi
i have a problem with my denford orac cnc lathe that i hope the people on
this forum can help me solve this problem
the lathe was converted to mach 3 about 3 years ago and has been a very reliable machine
until easter sunday this year when it decided that it would no longer do external or internal
threads , but still works very on normal turning jobs
the machine is using mach 3 version 062
i have tried a new cnc4pc spindle index board but this has not solved my problem as well a
few other ideas found on internet , the latest being a proximinty switch which i bought from
cnc4you this gives a very stable spindle speed but still no threading .
the problem when threading it is not picking the pitchin the same every time so all it
ends up with is alot of grooves
i have changed to a new copy of mach 3 on about 6 times just in case the program is corrupted
but still no joy
i have been stuggling with this problem for 7 months and have now run out of idea's so please
can anybody help me
thank you
robert

17

General Mach Discussion / Re: Mach3 Threading and Index Signal Problem

« on: May 25, 2016, 11:42:27 AM »

hi
i am using a breakout board with the parallel port , my c3 board is also blinking on the red signal led but it is not working properley , i have had word back today that one of boards one item on the that has 3 dry joints & also has a crack across 2 tracks & he doesn't like the boards because of all tracks on the board being a lot too narrow which makes very hard to get a good solder joint on the components
all the best
robert

18

General Mach Discussion / Re: Mach3 Threading and Index Signal Problem

« on: May 24, 2016, 03:13:28 PM »

hi
i am having the same problems with threading on my lathe which was working very well up to about 2 months ago then it started to play up , i am also using the C3 spindle index pulse board which i think is causing all my problems  , i have a collection of 3 of these boards which all seem to have the same problem on saturday i went to a model engineering exhibition here in the uk with 2 of the boards in my pocket hoping to find the problem from somebody & yes i found out that both boards had the same problem of dry joints on the same component
i am hoping that my boards are being repaired at this moment in time , these boards do not have a good reputation at the moment
all the best
robert  

19

General Mach Discussion / Re: spindle speed problem

« on: May 10, 2016, 02:44:26 PM »

hi
thank you for your quick replies , something i forgot to put in my original posting is that the speed is manually operated with a switch for on/off and a pot for the speed control
i will try all your suggestions tomorrow thank you
robert

20

General Mach Discussion / spindle speed problem

« on: May 10, 2016, 11:20:30 AM »

i have a problem with spindle speed not being shown in S true speed readout box , on start up of the spindle using the M3 command in a program the spindle starts up and the true speed readout shows the spindle speed but then goes straight down to zero , because of this happening the lathe will not thread . i have been trying to solve this for weeks even buying another spindle index board but this has made no difference . can anybody please help me solve this problem . this machine has run perfectly over the last 2 years with no problems
MACHINE
Denford Orac cnc Lathe
mach 3 turn version 062 with the standard lathe screen
using parallel port
stepper motors 10x microstepping with 4.2A stepper motor driver
C3 index pulse board - settings - output TTL & active low
slotted disc on spindle has 1 slot x 12mm wide