Messages

1361

General Mach Discussion / Re: Cannot do single point threading. What's wrong?

« on: November 11, 2008, 02:29:34 PM »

I will not 'run' Mach3 without buying the license. If I decide to go with Mach3, I will definitely buy it. The cost, as you point out, is minimal . . and it would not matter even if it wasn't. I don't do bootleg software.

Presently I am evaluating it and I have some concerns about the bugs that effect my own objectives and I also want to play with the interesting brain functions before I commit to this particular software.

It just strikes me that crippling single point turning in an evaluation version of a CNC control package is not a smart move. If I wanted Mach3 for a lathe, I would have moved on already. I think a timed eval would make a lot more sense.

As I said, it is not a big deal to me for my purposes, just an observation.

That being said, I will add though that I find it annoying to not have a distinct list in an obvious place of what is crippled so that I do not waste my time trying to get something to work that is intentionally disabled. I had no idea, for example that 'run from here' is crippled until I read your post.  I did notice that it did not work worth a hoot, but I chalked it up to another bug. I cannot seem to find the automatic Z axis feed increments either . . .  so now I wonder if I missed something or if it is intentionally disabled.

Wasting people's time unnecessarily is not a particularly good inducement for them to then spend money on your product . .  just another observation. 

1362

General Mach Discussion / Re: Cannot do single point threading. What's wrong?

« on: November 11, 2008, 12:55:14 PM »

Single point threading is not something I need to do so it would not prevent me from purchasing Mach 3. I am watching with great interest the bugs thread and I have encountered the CV problems described in various places. I have invested a lot of time in Mach3 at this point and I would much prefer to wait for the few issues that do effect me to get resolved rather than start all over looking at other software.


However, to the powers that be . . . what is the logic behind providing an evaluation version that is crippled to the point that it cannot be evaluated.

1363

General Mach Discussion / Re: Can someone explain the current draw of these stepper motors, please.

« on: November 11, 2008, 12:49:42 PM »

Hood, the numbers I gave are at the motor's current configuration, which is parallel.

Ray, thanks for the explaination. I do understand the relationships you described.

What was confusing me was that the Gecko drives (203v) require a resistor rated relative to the motor amps without regard for the operating voltage . .  that started me thinking I must not understand something about these steppers.

Perhaps the Gecko knows the voltage coming in and does some type of internal adjusment for the load useing the resistor only as a ref.

The fact that one of the three new Gecjo 203v broke after only 2 months also had me fearing I did somehting wrong in my setup. They found a bad component and replaced the drive for me, so all is well now . . plus I now have a spare.


In any event, good to know I have enough juice to drive my rig including the new 4th axis motor.

1364

General Mach Discussion / Cannot do single point threading. What's wrong?

« on: November 11, 2008, 11:50:21 AM »

I am evaluating the Mach 3 software on a converted X2 mill. Having seen a YouTube video of this mill doing single point threading using Mach 3 turn, I thought I'd give it a try.

My mach 3 is a demo version, and Mach3 mill seems to be working fairly well now on this mill.

Spindle has an index on it with a single slot. RPMs seem to display correctly in both mill and turn, but the cutter does not repeat in the same groove. It's just all over the place. I've started it as far as 1/4" away from the cut to give plenty of room to accellerate (Z axis driven my 640oz NEMA34 @ 4660 steps per inch).

I tried fiddling with the Z axis accelleration and speed (making it slower) and tried all sorts of different spindle speeds. Mach is not controlling the spindle speed, but I match the speed to what I command in G-code.

So, is the demo version crippled to not do single point, or is there something I have overlooked in getting this set-up to work.

1365

General Mach Discussion / Can someone explain the current draw of these stepper motors, please.

« on: November 11, 2008, 11:41:34 AM »

I put an ammeter on the power feed to a Gecko 20V. The current draw is unexpectedly less than half of what I anticipated, so there is something about this that I don't understand.


Motor is Keling 2.8 amp, 4.17v running off 36v power supply. It idles at about a half an amp and only draws about one amp at full stall.

Why is there such a difference?

I have a pair of 2.8 amp and a 6 amp motor running off an 8.8 amp power supply and I am adding a 4th axis motor (another 6 amps). I was about to replace the power supply with a larger one, but it seems the motors draw much less that I though so I may be OK with the PS that I have.

It is simply a question of higher voltage drawing less amps in the same motor?

1366

General Mach Discussion / Re: Jogging distance varies. Set to .001, jogs .0005 then .001, then .0015, etc

« on: November 03, 2008, 01:27:37 PM »

Thnaks for the comments.

The behavior I am talking about is in one direction.

I do have a lot of backlash in the Z, but that should not be effecting the movement in one direction. Certainly the standard X2 rack is not accurate, but I did shim behind it to take out most of the play.

I'm waiting on the timing pulleys to get the ballscrew installed on the Z axis. I have a new 640oz-in NEMA34 motor for the Z. I am going to end up with exactly 15,000 steps per inch on Z.

Currently the setup has 20,000 steps on X and Y with 425 oz-in NEMA 23 motors.

1367

General Mach Discussion / Re: Jogging distance varies. Set to .001, jogs .0005 then .001, then .0015, etc

« on: October 30, 2008, 06:25:15 AM »

Thanks for the reply.

For now I am using a timing belt to drive a pulley in place of the handle on the rack/pinion Z axis on the little X2. Down and dirty, but it got me running quickly. I looked at available retro fit kits for the X2, but the X2 has no quill, so in order to be useful for tapping, the ball screw would have to have a quick release of sorts and I didn't find any with such a feature.

The table has ball screws and the steps work out to 20,000 and I have not noticed the same issue . .  although those motors are NEMA23 so that is another variable.

I have finished a quick release design for the Z axis ball screw so I'll be converting that soon and it will also be 20,000 steps. After that the problem will likely go away, but I'm still lacking an answer as to where the problem comes from. Is it the Gecko, Mach3, the motor?  Is it solvable, or is it just intrinsic to the method used to calculate microstepping?


My understanding is that the control software (Mach3) simply sends steps and the Gecko (or other drive) is where the pulses are totalized and the microstepping is calculated. Maybe I have that wrong.

If this is intrinsic to stepper motors, that would be a compelling argument for servos.

I'm planning to sell the X2 at the end of a current project and launch into another CNC conversion using an X3 . . and perhaps servos.

1368

General Mach Discussion / Jogging distance varies. Set to .001, jogs .0005 then .001, then .0015, etc

« on: October 29, 2008, 11:01:15 AM »

Mach 3, Gecko 203V, Keling NEMA34, 4650 steps per inch.

With jog set to .001, the actual move varies between .0005 and .0015. Maybe three will be .001 and then it goes off again.

It always catches up and does not loose or gain overall distance . . .i.e. it repeats exactly to the same spot with multiple 1" long test moves, but I would not be able to use the jog for accurate depths.

Is this normal behavior? Is it coming from the Gecko drive or from MACH 3? Do I have something set wrong?