Stepper problem

[eurikain]

So sorry for the delay !

Have you measured the resistance between each pair of cables ie between red/blue black/yellow etc they should read all the same + or - a very small amount.

I will try tomorrow. How am I supposed to test this ?

Also as Dean has said re the printer cable make sure it is a straight through cable ie pin 1 to pin1, pin 2 to pin2 etc. AS when you say you have used it before was it on a printer? Not all printer cables are straight through.

I bought this cable brand new three years ago and only used it with my CNC electronics, never on a printer. I will check that all pins are straight through (actually, how do I do that with no juice on them ?) and get back to you tomorrow.

bi polar parallel wants more juice

Could I wire them in series ? Then they'll need 1.4A and I'll be fine (for now).

why don't you run them at a higher res?

What do you mean ? 1/16 or 1/4 ? FMD2740A can't do 1/8 or 1/4, only full, 1/2, 1/16 and lover.

Yes and also try setting the Step pulse so it's ahead of the Dir pulse. You'll find this in motor tuning.

Sounds good, I'll try that tomorrow and let you know. I'll wire only three motors and see what comes out. i'll post pictures/videos if I can.

[eurikain]

Update on my problems :)

Received my new $10 BOB last week and tried it today. I plugged only one motor. Works like a charm. Plug all motors, boom same problem as before. Unplug all motors and plug just one. Doesn't work with one motor anymore. I turned off the PC, unplugged everything from the BOB. Turn on the PSU and the motors, thought not moving, make a weird high pitch noise, that they make when they don't work correctly. On today's first attempt, the motor plugged was quite when still. So, I am assuming it's either the motors or the drivers.

[eurikain]

Update: my new AM882 drivers arrived a while ago. I wired my new BOB with one AM882, same PSU as before, same motors as before. The AM882 "stall detection" alarm activates when everything is under tension. Therefore, I am assuming that the problem comes from the motors. I will order cnc4you's motors some time later so we will know what was wrong :)

[eurikain]

Update:

I have:
- 4 brand new AM882 drivers
- brand new 5 axis bob
- 4 brand new CNC4YOU Nema23 3.1Nm steppers

AND I AM STILL HAVING THE SAME ISSUE oO !!!!

Would anybody be nice enough to spend a few minutes on Skype with me trying to figure this out before I go buy a new DB25 cable and new computer ? If you are willing to help then send me a PM and i can find any time to talk :)

Thanks a lot !

[uli12us]

Have you connected your wires in exact the same way, like jazz wrote months before.

If yes, have you tested the drivers (and motors) with a small program direct from your printer port of your computer. If you don't have, I must look, if I have one.

[Noplace]

is your BOB getting sufficient power supply? it's a long shot but worth to get a separate 5V power supply (phone charger with high amp like the samsung ones ) and try powering it from that. at worse case you will end up with an extra charger hehe.

[eurikain]

@uli12us

Hello :) Yes I am sure, I followed his instructions to the letter... I read carefully wiring diagrams from CNC4YOU and from the AM882 manual. I have checked several times.. I should try to plug my Mom's computer to see if the problem is not just the computer --'

I haven't tested the drives / motors the way you mention. How do you do that ? Drivers are brand new, they seem to work fine (they hold the motors in place when the Mach3 reset button is "up" and let them turn freely without power when it is "down").

@noplace
That, my dear, is a great idea, it's probably the only thing I haven't tried. I happen to have a PC power supply laying somewhere in my room.

[JAZZCNC]

Update:

I have:
- 4 brand new AM882 drivers
- brand new 5 axis bob
- 4 brand new CNC4YOU Nema23 3.1Nm steppers

AND I AM STILL HAVING THE SAME ISSUE oO !!!!

It's your Parallel port then. (or cable) Don't mess around buying new PC just buy an external Motion control card and you will be sorted out and have much better performance.
If you buy new PC or PP card and stick with PP at best it will work ok but compared to external motion control it will still be rubbish.

So Don't Mess about just buy one.!! . . . Promise you won't regret it.

Edit: I'm not a Fan of Skpe so don't have it on this PC. Also without being in front of machine it's of limited use with problem like this.

[eurikain]

@JAZZ here you are :D ! Thought you were on vacation :D (check you inbox ;) ). Can you recommend me a decent (please think about my student budget haha) one ?

[JAZZCNC]

@JAZZ here you are :D ! Thought you were on vacation :D (check you inbox ;) ). Can you recommend me a decent (please think about my student budget haha) one ?

I had seen PM just ignoring you. . .Lol . . . No it just slipped my mind.

I am thinking about your Student budget and you can't afford to not get one. I told you before not to buy drives or anything because wasn't your problem but you didn't listen.!! . . . . Some folks just need to learn the hard way.!. .