Topics

1

General Mach Discussion / relay control headache

« on: February 23, 2013, 08:32:33 AM »

Hello folks,
I am new to Mach 3 again (- I dabbled with it last year). My breakout board is similar to this one:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=181075135780

I follow this advice:
http://www.buildlog.net/blog/2010/07/mach3-laser-cutter-setup/

I am trying to setup mach3 so I can switch the relay on/off using M3-M4 and M5 or E1Px.. and can't get it to work. I read everything I could around, but still don't get it. The mill works, with this pinout


X 2-14       (step pin =2 dir pin = 14)
Y 16-3
Z 7-8
A 6-5
B 4-17

whatever I do in the MDI (M3, M4 M5 with a small move after, or E1P1 E1P0)... nothing happens. The relay does not click (I also check with a continuity meter - no connection is made)

could anyone talk me through the setup? I know it's basic... but I can't get it to work!

many thanks

Thomas

2

General Mach Discussion / transforming a list of x,y coordinates into a curve, then into gcode

« on: May 06, 2012, 04:39:39 PM »

Hi folks,

taking a short break from trying to remove backlash, I wanted to turn to something simpler...

I want to do some engraving of of Japanese characters, so I had some written and scanned scanned that. The image had grey zones (folds in the paper), so wrote a small python program to decide if a grey was a black or a white, then removed all the blacks that were not an "edge" of the picture - so I have now the outline of the character - neat.

now I could easily "read" that image and generate a long list of coordinates that need to be drilled - x,y pixels. But this would look bad - the spindle would move at x=0 from y=0 to y=end and drill every black pixel on that line, then do x=1 and y=0 to end and drill the pixels on that line... etc, rather like an old TV. This would look quite bad, especially given the backlash I have

What I need is all these pixels to be joined by a single line (okay, several as the lines don't always intersect in "holes", such as in the letter "O") that can be then drilled as a curve - any ideas of how I could do that?? I am sure there are programs that take a list of coordinates, finds the function that goes throught the points - that is what I need I guess!

If anyone is interested in sending me some picture files to see the output, please feel free! High contrast will give better results - see examples attached

many thanks

Thomas

3

General Mach Discussion / weird Z axis behaviour on Panther 210

« on: May 06, 2012, 06:19:47 AM »

Hello,

Along with my other issues ("newbie - help with solving backlash issues « 1 2 »"), my Z-axis is behaving strangely.
When using page-up, page-down, the spindle goes randomly up or down - e.g. it moves but not really in relation with the command.
In gcode I have the same issue - the Z axis seems to move randomly up or down when a Znn command is found...

any ideas?

Many thanks

Thomas

4

General Mach Discussion / newbie - help with solving backlash issues

« on: April 29, 2012, 05:19:24 AM »

Hi there

It seems I have some backlash issues with the small mill I just bought. Basically when trying to mill a PCB I get very poor results - track lines are not "closed", drill holes are misplaced etc. A member of the CNC forum has suggested it was backlash.
How do I solve this problem?
The manual I got with the mill is quite basic - see attached pdfs.
I followed the manual for the X axis. The "auxilliary nut" does not turn more than 30 degrees (the manual says "half turn"). When I put everything back together, it is markedly more difficult to manually turn the X screw.
When tackling backlash, is more resistance better? Or shall I look for the least resistance?

Any ideas of how I can solve this problem?

many thanks for your help

Thomas

5

General Mach Discussion / issues with PCB milling - newbie

« on: April 28, 2012, 04:38:31 PM »

Hello,

I have played with Mach3 for a couple of weeks - great! I bought a small milling machine called Panther-210, and I am trying to mill some PCB... so far with very little luck.
I draw my PCB using DipTrace/PCB layout, export the layer as a DFX file, then convert the DXF file with a small utility called ACE. This gives me g-code I can then import in Mach3.

The issues I have are:
1- most traces are not "closed": for example a circular pad would look like a "u" instead of a "o"
2-I tried to drill the PCB (just using an engraving tip with very small Z, just to see where it will be drilled), and the holes are not well centered
See attached picture

basically the PCB is unusable with all the tracks not being disconnected from the rest of the copper plane.

The feed rate I use is 30inches per min.

Where does the issue come from? Is it the accuracy of the mill? How can I improve that? The mill is sold as a small PCB mill, and I have used the settings recommended from the vendor:
e.g. velocity is 1400 mm/min, accel 150 mm/sec/sec...etc

many thanks for your help

Thomas

6

General Mach Discussion / using "Write/text engrave" wizard in demo version?

« on: March 10, 2012, 03:27:13 PM »

Hi there,

Are the wizards disabled in the demo version? I am trying to use the "Write/text engrave" but can't get G code out. Snapshot of my screen attached (the "Script" button bottom right is not there)

many thanks

Thomas

7

General Mach Discussion / setting up Mach3 with unknown belt on XY table

« on: March 08, 2012, 03:49:51 PM »

Hi folks,

I have inherited a XY table that was use to taked samples from a plate. The axis can move about 24 x 17 inches or 60 x 45 cm. The X stepper drives a belt, the Y stepper drives a long lineshaft(?) along the X axis, that in turns drive a belt. The steppers are PK268-03B (3V, 3A, 200 steps per turn) - datasheet attached (see page 241) if it helps.

How do I set my "Motor Tuning" variables, since I don't know the specs of the belts and the lineshaft?
The wheel (sorry don't know the proper term) driving the belt has 32 teeth, the belt has 1 tooth every 5mm... I guess it means that one turn of the wheel should move 32 belt teeth, or 16 cm... but if I turn the stepper manually one full revolution the X carriage moves about 8-9 cm (some calculations must be wrong here...)

So I assumed 3200 steps for 80 mm, or 40 steps per mm. If I use these settings... the steppers get noisy, but nothing moves.

Also, the table tends to vibrate at lower speeds... is there a rule of thumb for smooth operations?

many thanks for your help -

Thomas

8

General Mach Discussion / Questions on driver rating and PSU rating - newbie questions

« on: March 05, 2012, 06:58:11 AM »

Hello,

I'd like to power 3 steppers motors FL86STH80-4208A (4 phases, 4.2 A per phase), datasheet attached. I will only use 2 steppers in the near future, but would like to be able to add a third later. The wiring I am using at the moment is bipolar (parallel) connection... The steppers will be used for relatively light work (for example a sand plotter as shown by Bruce Shapiro), maybe a small mill.

I think my steppers are well over specs for my actual needs, but I have two of them and would like to avoid buying more steppers.

My question is about the power supply I need and the amp rating of the drivers (datasheet attached) ... my online seller first told me that a 36V 10A power supply and  4.2 A (max) drivers were fine for this, ... Is this right?

From the specs of the stepper in parallel connection I apparently need 6A (4.2 * 1.4) A ... so it looks like 6 * 3 = 18A. So my power supply looks too small

As for the drivers the max amperage is 4.2A - this again looks under-powered if I use the stepper in parallel connection...

Now the seller is okay swapping my drivers (at a cost) for drivers that can handle up to 7.2A (http://www.ebay.co.uk/itm/CNC-Mill-Router-DIY-Stepper-Driver-Board-Controller-MA860H-2-6A-7-2A-24V-110V-DC-/270917084995)

Should I do this, and also get a new power supply? What power supply would you recommend?

many thanks

Thomas

9

General Mach Discussion / newbie - help needed please

« on: March 03, 2012, 12:47:17 PM »

Hello,

My name is Thomas and I just started playing with steppers and Mach3. It seems that I can't get anything to work right now... help would be very much appreciated
... I have no experience at all using Mach3. Datasheet for the stepper and the references for the board/drivers is attached.

In Mach3 (R3.042.040, running with XP on an up to date computer ... I installed it, rebooted, ran the driver test: freq. is 25kHz, it says "System Excellent")
-I have setup the correct address (0xccc8) for the port after checking it in my device manager

-I have modified the Estop to "active low" in Ports and Pins/Input signals
-I have modified the Step pin# and Dir Pin# in Ports and Pins/Motor Output using the breakout board specifications

- I have wired my  FL86STH80-4208A (8 wires, 4.2A) in bipolar (parallel) connection... I also tried bipolar series and half coil connections - same result
-when I try to run the simplest G-code possible (X100) I get irregular, small steps. I can get the motor to step the other way by running X-100, but the steps are also small, and irregular...

As far as I know the connections between the breakout board and the driver are fine (checked 3 times).
If I look at Mach3/Diagnostics "Port 1 Pin current State" Pins 4,5,6,7,8 are green

I tried to install Mach3Version3.043.022 instead, doing everything the same way as before, and in this case I don't get any steps at all... and all pins are black in If I look at Mach3/Diagnostics

Is there anything obvious I am missing?

many thanks for your help

Thomas


the power supply should supply enough power (36V 10A), the driver is set up at 4.2 A (I guess it should be higher given the bipolar parallel connection) - I will change that later


data:
I use Version R3.042.040
my stepper is a FL86STH80-4208A (8 wires, 4.2A)


I have setup my 8-wire stepper in bipolar (parallel) connection


the breakout board and drivers are here:
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&isIU=1&item=180826693743