Messages

1

SmoothStepper USB / Re: Ethernet Smooth stepper and The PMDX-126

« on: April 08, 2015, 06:32:31 PM »

I'm not familiar with the CM-106. Although I live in the UK, I like the support I get from across the pond and wouldn't like to have to install a board with badly translated manuals and where support might be difficult. I've needed to speak to the guys at PMDX and it was a good experience. They have the technical competence and language skills to have a proper conversation that solved my problems immediately. One of the things I really like about the PMDX product range is the modular nature of their products. If you need PWM spindle control, you can add it. If you want a SmoothStepper you can add that too. It all works nicely together. The only downside is that you have to use a USB pendant and the one they recommended didn't work and I've been waiting for a replacement for 6 weeks now.

Regarding the lathe, my ACL has gang tooling rather than a tool drum unfortunately, so I'm not much help here.

2

General Mach Discussion / Re: Feeds and Speeds Milling Aluminium

« on: April 06, 2015, 06:42:27 AM »

There is some good advice here: http://blog.cnccookbook.com/2012/03/27/10-tips-for-cnc-router-aluminum-cutting-success/

3

General Mach Discussion / Re: Macros cause missed steps with 2010 ScreenSet & SmoothStepper???

« on: April 05, 2015, 07:01:30 PM »

Thanks Jeff, I'll go back to .062. I have the latest SmoothStepper ESS plugin from the Warp9 website already installed.

If the problem was a motor tuning issue, wouldn't it affect the identical G01 motion in the same way? As far as electrical noise is concerned, the wire from the touch plate is just a length of instrument wire that goes to a junction box. The same type of wire is used to pickup the spindle body and it goes to the same terminal block. From there they both go to the PMDX-126 via unshielded 2 core flex. Should this all be shielded and one end earthed?

4

General Mach Discussion / Re: Macros cause missed steps with 2010 ScreenSet & SmoothStepper???

« on: April 05, 2015, 06:27:29 PM »

The macros I'm running were written by Gerry (Ger21) and contain the required While IsMoving() ... Wend code. I did, however, add a sleep 100 in each loop to give windows a chance to grab some clock cycles, although this is probably not necessary in Windows XP, which does multi-tasking properly (unlike earlier versions of Windows prior to NT).

I thought I'd got this fixed, but just done some more testing and I'm losing steps as the G31 is executing. If I move the tool to Z100 (work units) and execute G90 G31 Z20 F300 the tool moves downwards, but with lots of missed steps until it hits the plate, when it stops. If I move back to Z100 and execute G90 G01 Z20 F300 the tool moves downwards smoothly with no missed steps. This problem now seems to have nothing to do with macros. For some reason the G31 can't reliably move in Z without losing steps.

I've tried Mach3 version 3.043.062, but that didn't fix the problem and I'm currently on .057, so I'll go back to .058 and see if that is any better.

Jeff, is there anything in the config of Mach3 or the SmoothStepper that I should look at?

TIA

5

SmoothStepper USB / Re: Ethernet Smooth stepper and The PMDX-126

« on: April 05, 2015, 01:42:56 PM »

I've got a router with PMDX-126 and SmoothStepper ESS. My original controller kept missing steps in Y so I upgraded my PC to a Pentium 4 2.8GHz, but that didn't fix the problem. I remade all the wiring and checked the earth loops and noise, but that didn't fix the problem either. Then I rebuilt the controller with a PMDX-126 and SmoothStepper ESS and now I've got a sweet machine that is fast and accurate. Both products are awesome, with great service backup and good (excellent) documentation. I'm just about to rebuild a Boxford ACL cnc lathe and I'm going to use PMDX-126 and SmoothStepper ESS again.

6

General Mach Discussion / Re: Macros cause missed steps with 2010 ScreenSet & SmoothStepper???

« on: April 05, 2015, 01:25:53 PM »

I uninstalled Mach3 version 3.043.066 and installed version 3.043.062 and retested. This did not fix the problem so I went back to version 3.043.057. This version did fix the problem.

As ever, great advice from Gerry - thank you sir.

Now what issues will I encounter that were fixed between version .057 and .066 I wonder???

7

General Mach Discussion / Re: Macros cause missed steps with 2010 ScreenSet & SmoothStepper???

« on: April 05, 2015, 11:42:23 AM »

Thanks for the help Gerry. I think you're right. After further testing this afternoon, I've discovered that it is the G31 that doesn't work properly. If I run the following test program that simulates what the macro is doing:

F300
G90 G31 Z-120    (Probe downwards until either the plate or Z-120 is reached)
G91 G01 Z1        (Move up 1mm from the touch point)
F25
G90 G31 Z-120    (Probe downwards again slowly)

With the tool starting about 50mm above the plate, the first probe movement loses lots of steps but does touch the plate, backs-up and re-probes slowly. At the end of the program I zero the Z axis and then jog Z upwards by 100mm. If I then run this bit of code:

F300
G01 Z0.1

This moves the tool smoothly and without losing steps to just above the plate. I can then just get a 0.1mm feeler under the tool (it's tight, but expectedly so). This proves that steps were not lost in the rapid jog upwards and the G01 downwards (unless exactly the same number of steps were lost in both journeys).

My next thing will be to go back to the earlier version of Mach3 as Gerry suggested and see if that fixes the problem.

8

General Mach Discussion / Macros cause missed steps with 2010 ScreenSet & SmoothStepper???

« on: April 05, 2015, 10:09:58 AM »

I have a router with Mach3 version R3.043.066, SmoothStepper ESS version ESS_v10r2d1d and a PMDX-126 breakout board. This is all running on a dedicated bare bones PC with Windows XP SP3 installed. The machine has been running perfectly with good repeatability and no missed steps. I wanted to install the 2010 ScreenSet from cncwoodworker because it has a really neat set of macros including a couple that make tool changes a breeze. So I installed the screen set, following the installation instructions to the letter. I installed a fixed plate and movable plate on my machine and hooked these up to the correct input on the PMDX-126 and configured the probe in Ports&Pins. So now for a quick test. Clicking the Quick Zero icon in the 2010 ScreenSet initiated a probe and my Z started to move down, but the stepper was clicking as it lost steps. When the tool reached the movable plate it stopped and reversed direction. But, instead of backing up 1mm it carried on backing up to where it started from. Something not quite right here so I decided to look at the M889 macro while Mach3 was still running. The code all made sense and I put a couple of comments in and saved the file. Just out of curiosity I clicked the Quick Zero button again and this time the Z axis moved down without missing steps until it reached the plate and then backed up 1 mm, changed the feed rate to SLOW and went to touch the plate again. After it got the touch it did a G0 to clearance Z exactly as it was supposed to.

So I thought, great - I've fixed it so I shut down Mach3, fired it up again and repeated the test and this time it was not fixed unless I opened and saved the macro file whilst Mach3 was running. I did this test about 12 times and got repeatable results - first time after program start it doesn't work, but if you then open and save the macro code whilst Mach3 is running the macro works correctly every time.

Has any one got any ideas how to track this down. My suspicion is that the SmoothStepper and the ScreenSet are not working nicely together. Or maybe it is the SmoothStepper and Mach3 when executing macro code. I have used the SmoothStepper for hundreds of hours and never had any hint of missed steps until now. This is the first time I have used a macro to generate and execute G-code. Does Mach3 execute G-code in a macro differently to executing it from a file?

Any help is gratefully received so TIA.

9

General Mach Discussion / Re: Feeds and Speeds Milling Aluminium

« on: April 05, 2015, 09:33:52 AM »

I would suggest that your using the wrong cutter. In alloy you want either a single flute or 2 flute cutter. There are software tools to help with feeds and speeds. The one I use suggests for a 3mm dia 2 flute cutter with a cut depth of 1.5mm the spindle speed should be 16,000 rpm and feed rate 950mm/min for roughing (notice I'm European and don't use inches) and 14,600 rpm and 485mm/min for finishing. The most important thing I've found is chip clearance. You have to be completely paranoid about re-cutting chips, so you need good coolant flood or high pressure mist to blow the chips away otherwise they get stuck to the cutter and it'll break. I generally use a single flute cutter with all aluminium alloys and can still have chip clearance issues if my misters are not getting the chips away. With a 4 flute cutter they will always get stuck because they get trapped in the flute even if you've got good coolant.

If your machine can't go that fast, and you mentioned 8,000 rpm, then the feed rate for roughing should be about 460mm/min and for finishing 265mm/min at 8,000 rpm.

10

General Mach Discussion / Re: Stepper screaming

« on: December 07, 2014, 05:52:38 PM »

I've spent today playing with my router and discovered that the problem is due to my Backlash configuration. When I turn Backlash compensation OFF everything moves sweetly.

What I did to fix the problem was to increase the value for Shuttle Accel. (in General Config...) from 0.01 to 0.05. Now I have Backlash compensation working and high rapid speeds.