help with problem please

[martin54]

Guy I know had a machine converted to run on mach3, when I say had a machine converted what I mean is that someone ripped his old machine to bits, connected some of the new bits together & then disappeared leaving Wullie with a non working machine. I have tried to help out but not 100% sure what I am doing.
The PC running mach3 works fine & I have also tested it on my cnc to make sure it runs, the serial cable has also been tested, the motors are wired up round the right way & when the system is started you can hear/feel them lock. If you plug the pendant control into the BOB the motors all move the right direction as they should.
Now when you try to move any axis under mach3 control the axis light on the BOB lights the DRO on the screen moves but the motors don't any help would be really appreciated

[JAZZCNC]

Martin need more info on the BOB and pins motors are connected to and electronics. Also Limits and E-stop pins if any fitted.
If possible post or email me the mach3 XML your using. You will need to Zip up the XML. you will find it in the mach3 folder under the name of the profile your using.

[martin54]

Sorry about the late reply, the guy is going to sort out all the details, not sure if things have got better or worse lol, have now got the machine moving on all 3 axis but for no apparent reason on 2 of the axis after a couple of minutes or so the motors stop moving. The DRO's are still moving in mach3 if you jog about but the motors don't move. Have to turn the power off & back on to get them moving again, same 2 axis all the time, "Y" axis & "Z" axis.

[JAZZCNC]

Sorry about the late reply, the guy is going to sort out all the details, not sure if things have got better or worse lol, have now got the machine moving on all 3 axis but for no apparent reason on 2 of the axis after a couple of minutes or so the motors stop moving. The DRO's are still moving in mach3 if you jog about but the motors don't move. Have to turn the power off & back on to get them moving again, same 2 axis all the time, "Y" axis & "Z" axis.

Well if you haven't all ready start by pulling on all wire connections to check there are no lose wires.

[martin54]

no loose wires Jazz, it's the same 2 axis all the time, machine jogs about great when first started then you go to jog either the y or z axis & the motors don't turn but the dro on mach3 is moving

[JAZZCNC]

no loose wires Jazz, it's the same 2 axis all the time, machine jogs about great when first started then you go to jog either the y or z axis & the motors don't turn but the dro on mach3 is moving

Try swapping X axis drive with Y axis or Z axis and see if it moves. This will confirm or eliminate the drive from picture.

[JAZZCNC]

As it got a shity cheap chinese BOB.?

[martin54]

As it got a shity cheap chinese BOB.?

Yer & cheap Chinese drivers as well, he bought 3 drivers & a bob, wired it all up & the x axis driver blew up, seller told him to try again & he blew up another driver lol, was asked for pictures to ensure all was wired correctly & after sending the pictures was sent a complete new set of drivers & bob, still no joy so seller sent another bob

[JAZZCNC]

Yer & cheap Chinese drivers as well, he bought 3 drivers & a bob, wired it all up & the x axis driver blew up, seller told him to try again & he blew up another driver lol, was asked for pictures to ensure all was wired correctly & after sending the pictures was sent a complete new set of drivers & bob, still no joy so seller sent another bob

Ok Well sounds like he needs to take the Hint and buy some decent gear.! . . . . . Bet there the TB based drives as well.?

That said Because 2 drives are going off at same time I'd be inclind to think it's the BOB not the drives but swapping the good working axis drive will show up if it's the drive or BOB.?

Not something I'd recommend unless the person is confident with electrics is to by pass the BOB all together and wire direct from the PP pins but this is a risky move and could blow the PP if not done correctly. So only for the competent hacker really.!

[martin54]

will try switching the axis around to see what happens, could probably use my bob to test the machine if I had to, I know that works fine lol

[JAZZCNC]

will try switching the axis around to see what happens, could probably use my bob to test the machine if I had to, I know that works fine lol

Would only do that as a last resort if it's not a spare BOB. Could be something else killing the BOB, if indeed it is the BOB, doubt somethings killing it it but could be.!
Something I would try that wont hurt is your parallel port cable.! . . . In past I've had cables give silly troubles but often they just don't work or are irratic never worked then stopped so it's a clutching straws move. But still easy try so worth doing for elimination purposes.

Another thing worth trying that won't hurt and is a big elimination is trying your PC. This takes the PP and software out the equation which are both candidates for trouble.!

[EddyCurrent]

Mine was doing that while messing about tuning the motors, I had the velocity and accel too high which was making them stall and trip out. The DRO was still going but the motors were not, to reset them involved power off/on cycle. They worked in jog due to lower settings.

[JAZZCNC]

Mine was doing that while messing about tuning the motors, I had the velocity and accel too high which was making them stall and trip out. The DRO was still going but the motors were not, to reset them involved power off/on cycle. They worked in jog due to lower settings.

Don't think this will be the same Eddy. Yours was caused by the wrong tuning stalling motors which tripped the stall detect built into drives which then needed power on/off cycle to reset the drives.! . . . . No such nicetys here I feel.:dejection:

But it could be tripped motors from being tuned to close to edge and when machine gets hot after 10mins things tighten up and cause binding so worth knocking tuning back to see. . :applause:

Being 2 motors at same time makes think not thou.!!

[Clive S]

It might be worth blowing cold air over the driver chips to see if they are over heating and tripping out. ..Clive

[EddyCurrent]

Are the drivers compatible with the motors ?

[martin54]

Jazz, using my computer isn't really an option as it's built in to the machines old control box BUT I did use his computer to run my machine to eliminate the PP & the software, worked no problem at all. I also tried my serial cable on his machine to rule that out lol, Plus as the seller has now sent him 3 different bobs he has 3 cables of his own that we have tried as well.

Eddy, I've tuned the motors & backed them off far enough from their maximum that it shouldn't be a problem but the machine was doing it before I tuned the motors & the initial setting they give you to plug in to mach3 are so slow I can't see it being a factor. Compatibility I haven't got a clue about if I'm being honest but all 3 motors are the same & only 2 axis seem to have this problem. Jazz is right there are no safety cut outs with this stuff lol

Clive, it had crossed my mind that it might be down to heat in some way but wasn't sure what to do to try & eliminate anything like that, will try a couple of fans blowing on them.

Thanks for the help & suggestions people, gives me something else to try.

[martin54]

Thanks for all the suggestions on this one, lesson here to be learnt is never assume someone else has done things correctly lol

As I said in the first post someone else had started the job of replacing the electronics on this machine & then disappeared, spent a bit more time with the machine on Sunday & made some discoveries that I hadn't considered before because I assumed things had been done correctly.
Motors seemed to be far to cold so had a look at the dip switch settings on the drivers & apparently they hadn't been set at all, amps were set at 0.6 lol
Altered that & while waiting to see if the drivers warmed up at all I brought up the diagnostic page within mach3, the home switches were all flashing on & off randomly & if you pressed one it lit up but still flashed on & off a little. Killing power to the motors sorted the problem & further investigation revealed that the motors had been wired with trailer cable. 7 core cable with 4 cores being used for the motors & 2 cores for the home switches. Disconnecting the home switches seemed to stop it tripping the 2 drivers.
So now there is 4 core cy cable on its way for the motors & I have shielded twister pair which I will use to re-run the homing switches.
Hopefully once that is done it will run without any problems lol.

[Clive S]

Well spotted, and a good lesson for all regarding essential screening of motor cables and keeping them away from signal lines. ..Clive

[JAZZCNC]

Thanks for all the suggestions on this one, lesson here to be learnt is never assume someone else has done things correctly lol

Yes Assumption is the mother of all F'#K up's and me inparticular should now better I've been caught wit it so many times.!! . . But we/I are all guilty in this case as well because I just took it as a given or assumed you'd have checked the drives were setup properly from start.!! . . . . Shame on US for not thinking to ask, Shame on you for being a WALLY and not checking first. . . Lol