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This should be it.
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electronic lead screw
- Thread starter greenail
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My driver is set for 8 microsteps.
I am unfamiliar with the term "damper plate technique"
Sorry posted earlier in this thread.
A search on steppers should reveal. A co., in think in France makes them.
Its a simple disc of steel, scaled according to stepper size, fitted onto the shaft w grub screw, to help dampen mechanical resonance.
But at 8 micros u simply may be running it up to its limits, depending on its inductance, etc.
If its a mech resonance issue, u can usually hear it growling, or not sounding smooth.
Cheers!
Cant find his ballscrew measuring vid... huge no. Of Vids!
ah goofed, Not French! but Oriental Motors make dampers and a bit more than just a lump of steel..
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edit: somehow, I missed your attachments. Disregard the following two sentences.
Here is an article on stepper motors that some may find interesting. One thing that I may try is adding a large capacitor to the driver p.s. input. Most switching supplies have limited capacitive filtering, relying on feedback to keep the output voltage constant and it may be that the motor instantaneous current demand exceeds the p.s. capability.
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There are other reasons you might want to add bypass capacitors to the power supply lines at the driver end of the connections. Inductance of the connector wires, if they're long (or form a loop with substantial area between the line and ground return), could produce transients.
I once was designing an audio amplifier, and this particular design produced some really nasty transients on its output when driven with a fast square wave. I tried all kinds of things in the circuit, to no avail -- until I put an oscilloscope right on the output transistors' collectors (the power supply inputs). Lo and behold, a really nasty transient! Bypass caps right next to the output transistors cured the problem. It didn't matter how beefy the PS wires were -- that has a small impact on the inductance.
I once was designing an audio amplifier, and this particular design produced some really nasty transients on its output when driven with a fast square wave. I tried all kinds of things in the circuit, to no avail -- until I put an oscilloscope right on the output transistors' collectors (the power supply inputs). Lo and behold, a really nasty transient! Bypass caps right next to the output transistors cured the problem. It didn't matter how beefy the PS wires were -- that has a small impact on the inductance.
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I did a couple of cuts using the ELS. I successfully turned a length of 1" HR with a feed of .030"/rev. and .030" d.o.c. @ 588 rpm. If I did the math right, that amounted to 1.66 cu. in./min which is a fairly healthy stock removal rate. This amounts to a feed of almost 18 ipm and a stepper speed of 423 rpm. (I use a 2:1 gear box reduction) so my stepper rpm is twice my lead screw rpm.)
When I tried .030"/rev. and .050 d.o.c., it stalled the lathe and chipped the insert in the process.
Looking a no load ceiling, at 3 mm/rev, the stepper tracks but it fails at 3.5mm/rev. This corresponds to stepper speeds of 1667 and 1945 rpm, and 69 and 81 ipm, respectively.
With that, I am fairly convinced that the ELS will be able to handle my needs.
When I tried .030"/rev. and .050 d.o.c., it stalled the lathe and chipped the insert in the process.
Looking a no load ceiling, at 3 mm/rev, the stepper tracks but it fails at 3.5mm/rev. This corresponds to stepper speeds of 1667 and 1945 rpm, and 69 and 81 ipm, respectively.
With that, I am fairly convinced that the ELS will be able to handle my needs.
The mechanical Dampers may not be made any more as driver tuning mitigates the mech resonance issue somewhat.
Servo's easier to drive, & good drivers now have great PID tuning!
Thanks for the PDF, yes, unregulated linear supplies are actually a better choice than smps.
Reason is they are 'softer'.. I mean they have nice big filter cap, pref. Low ESR, but also they are able to 'flex' a bit with the load. Smps cant, they're tightly reg'd. In the old days the unreg'd supply had a ballast resistor in series with the common lead of unipolar steppers. That R provided 2 features, load 'softening' to stop coil burnout, thus allowing a higher headroom voltage, (to overcome motor coil inductance), and also dampened coil resonances a bit.
You are probably aware of all this, but stated for those that may be interested.
Yes important to have that reservoir cap at the driver input, lowest ESR Panasonics!