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jonm
24-10-2009, 12:23 AM
hi
what speed can i expect from a wood router running 3nm nema 23 steppers on 3 axis, using the diycnc sytem 3+ board, 2 amp per phase
24 volt power supply , i can only get about 80mm per min in mach 3 painfully slow

John S
24-10-2009, 12:35 AM
:feedback:

More info needed.
What screws and pitch, what microstepping selected ?

.

Gary
24-10-2009, 12:42 AM
Microstepping resolution? lead of the screw? or motor RPM? Any gearing or direct drive?
Type of screw Lead or ball?


hi
what speed can i expect from a wood router running 3nm nema 23 steppers on 3 axis, using the diycnc sytem 3+ board, 2 amp per phase
24 volt power supply , i can only get about 80mm per min in mach 3 painfully slow

jonm
24-10-2009, 12:52 AM
hi
1/8 step, 3mm pitch one start trapezioid screw, direct drive

Gary
24-10-2009, 01:48 AM
That is very slow, you should get far better speed than that.
Is this while cutting or rapid moves?


hi
1/8 step, 3mm pitch one start trapezioid screw, direct drive

jonm
24-10-2009, 01:54 AM
hi
just got the router going have a pen fixed to the z so just drawing with g code , as the z axis travels along the steppers pitch ( as in sound) gets higher every two or three seconds

tribbles
24-10-2009, 10:19 AM
That sounds like acceleration could be way way way too low - if the pitch gets higher every so often, then it's probably ramping up.

irving2008
24-10-2009, 12:00 PM
I would expect those steppers, even on 24v, to handle 2000 full steps/sec easily, thats 10rps, 600rpm or 1800mm/min with little load...

80mm/min = 26rpm = 0.43rps, 86 full steps/sec

have you told MACH3 you are using 1/8 step?

It does suggest your MACH3 settings are wrong...

HiltonSteve
24-10-2009, 04:12 PM
It does suggest your MACH3 settings are wrong...

Just about to say the same thing....

Take a look at the attached image which are the MACH3 motor tuning settings for my router and let us know what figures you have, don't use these settings as they will be incorrect for your machine.

jonm
24-10-2009, 04:26 PM
hi irving
i have the "steps per " in mach set to 533.3
200 X 8 = 1600 divided by the screw pitch which is 3mm = 533.3
maybe i am missing something here

resolution seems good i drew a 300mm diam circle and measured it to exactly 300mm

but the speed is very slow

John S
24-10-2009, 04:30 PM
Are all the axis free? no binding ?

jonm
24-10-2009, 04:40 PM
yes john everything seems free without the screws attached light finger pressure will move them

HiltonSteve
24-10-2009, 05:07 PM
It is the velocity and acceleration figures that adjust the speed, what are they set to?

jonm
24-10-2009, 05:20 PM
1072hi
i have tried various settings in here

John S
24-10-2009, 05:28 PM
Right the maximum you can do with this is 177.18mm / min if it can get up to speed in time hence your 88mm/min or suchlike.

Leave the steps alone and increase the velocity to 2,000 to start and acceleration to about 150 as a start point.

.

jonm
24-10-2009, 05:39 PM
thanks john
so my steps are set right , will try the settings you suggest, i knew i should be able to get a bit more speed somehow, if i can even get to 1000mm a min i will be happy

jonm
01-11-2009, 08:05 PM
managed to get my speed up , wired the steppers bipolar single coil
at 2.5 amps the 3nm motors are down to about 2nm but the speed has increased quite considerably can get about over 1000mm/min

tribbles
02-11-2009, 12:39 AM
If you increase speed, then the torque will inevitably go down.

What was the problem?

(Glad you got it sorted!)