Topics

1

General Mach Discussion / questions about the G201x

« on: July 03, 2013, 07:45:46 AM »

I am replacing the Keling driver with a G201x. Here are my questions:
1. how is the driver set for half step or some other step?
2. Since the current limiting resistor is optional, why  is it that the motor, within a few minutes of it being turned on, is warm to the touch while the other motors, driven with the Keling drivers are cold and warm up only after a good run?
3. The motor's specs are 2.8a  1.5 ohms, 6.8 mh and they are wired with an 80v ps in bipolar.  Should I use a current limiting resistor?
4. What should mach3 resolution be set at for this driver?

I have not blown the unit, and I want to be sure I get a better feel for these drives.
thanks
tony

2

General Mach Discussion / cannot run Mach from mid point

« on: March 30, 2013, 12:49:22 PM »

Why is it that if try to start Mach 3 from "run from here", the machine goes way off its coordinates?  I've done it  hundreds of times with different code and it always worked fine.  This is a new project, with new code, and it runs fine if I start from the beginning.  If, on the other hand, I bring the machine home, and then set a point in the code other than the beginning, the machine forgets its coordinates.  Why am I missing?
tony

3

General Mach Discussion / Great mystery.......

« on: March 28, 2013, 11:18:27 AM »

I was getting some slippage when I went from balsa to mdf. So I decided to change the accel velocity for my k2cnc 2514.  I set the new velocity to 70 ipm and the acceleration to 80 in order to make the x and y axis slip.  For this machine, 110 ipm is the maximum speed. To my amazement, neither axis, even when I place a load on it, slips.
I reduced the acceleration to 30 out of fear, but I am still puzzled by the fact that I cannot make the motors slip at such a high acceleration number.  A long time ago, I place damping wheels on all three motors to reduce resonance. I remember that this helped a lot in reducing slippage.
Any ideas? My steppers put out some 280oz/in and my drivers are set at a half a step. My power supply is a healthy 80volts.
I had not trouble running the machine faster with Balsa, but with MDF I assumed that it had to run much, much slower  due to the fact that the parts were not cutting precisely.

Another thing I noticed is that when I set the pulse rate to a number other than 0, Mach 3 brings it back to 0. Is this normal?
thanks
tony

4

General Mach Discussion / need simple procedure for autozero script using multiple tools

« on: March 10, 2013, 08:43:41 AM »

Can someone point me to a 1-2-3 procedure for working with multiple tool changes( manually) in one program when using an autozero tool offset script.  My few attempts have broken into my autozero touch plate, which fortunately sits on a plastic project box rather than steel. It saved me a tool, but it has ruined two touch plates so far. I need to know the procedure for, let's say, Tool 0 or 1 as the datum tool, and then subsequent tools, all using the autozero script.  Again, not to repeat myself, I have no trouble when I am working with only one tool. As soon as I start working with multiple tool lengths, I am totally confused regarding the sequence of steps and this is when I break parts. With an advance thanks.
tc






It's

5

General Mach Discussion / Still one more question on tool wear

« on: March 03, 2013, 08:41:59 AM »

As the code illustrates, the program is set up for tool wear compensation.  My understanding of how Mach 3 works is that only the diameter of the tool in the tool table is recognized for "wear". This is fine , except that if I enter a tool diameter that's smaller or larger than the actual tool diameter set in the program code, nothing happens.
If, however, I enter only the "offset" that I am looking for, then Mach 3 makes the change. For example, if I have a hole cut at .375 with a .125 diameter tool, entering .120 or .130 in the tool table does nothing.  If I enter +.005 or -.005 in the table, in the tool diameter column, then Mach 3 will open or close the hole by that amount.  Is this the way Mach 3 tool comp works? Or is there something missing in Mach 3 configuration? thanks tc
(POST DEV  - NovaLab)
(NWDTOOL N" 1/8 FLAT ENDMILL" T1 D0. F.375 L2.25 CD2. CL1. SD2. C0)
(NWDSTOCK X5. Y12. Z.375 OTC OX-2.5 OY-6. OZ0.)
N100 G00 G17 G20 G40 G49 G80 G90
N110 T1 M06 ( 1/8 FLAT ENDMILL)
N120 (MAX - Z.25)
N130 (MIN - Z-.25)
N140 G00 Z.25
N150 G00 X1.388 Y1.2101 S2000 M03
N160 Z.2
N170 G01 Z-.125 F36.16
N180 G03 X1.513 Y1.0851 I.125 J0. F26.16
N190 X1.638 Y1.2101 I0. J.125
N200 X1.513 Y1.3351 I-.125 J0.
N210 M00 (WARNING-CUTTER COMP APPLIED ON ARC MOVE)
N220 G41 D1 X1.388 Y1.2101 I0. J-.125
N230 G01 Z-.25 F36.16
N240 G03 X1.513 Y1.0851 I.125 J0. F26.16
N250 X1.638 Y1.2101 I0. J.125
N260 X1.513 Y1.3351 I-.125 J0.
N270 X1.388 Y1.2101 I0. J-.125
N280 G00 Z.25
N290 G40 M05
N300 G90
N310 M30
%

6

General Mach Discussion / Tolerance puzzle.....

« on: February 20, 2013, 08:43:43 AM »

I don't get to do pocketing often, but when I do I am puzzled to see that the difference between my drawing dimensions and actual pocketed dimensions can vary by as much as .020". I use Mastercam and compensate for tool wear; there's no noticeable backlash that I can see. Have I forgotten something in Mach3?
In my case, I simply have a rectangle measuring .406 wide, and the actual cut pocket width measures .393". I am using a .125 end mill compensated for .002 wear.
thanks
tc

7

G-Code, CAD, and CAM discussions / procedure for reworking a work piece

« on: November 28, 2012, 12:25:15 PM »

 I've already cut a piece which has two holes that I would like to move to another location on the same piece. Naturally, I no longer have the x-y coordinates on the machine. Is there a procedure that would allow me to precisely place and drill new holes on the piece?  I was thinking of using the two existing holes on my piece and use this as a datum points for establishing new xy coordinates on mach3, but this requires a lot of trial and error, I think.
tc

8

General Mach Discussion / How to make z tool cut deeper on the fly.....

« on: September 28, 2012, 11:01:45 AM »

I am cutting wood products, so there's little concern for tool breakage.  I set my Z to touch the work stock before I start cutting.  However, at times due to mild warping, the toolsdoes not fully cut through the work.
Other than changing the length in G code to a longer depth,  is there an easy way to do it with Mach on a temporary basis?  I know I can "fake" the z number before regenerating the toolpath, but then I cannot ever use the "go to zero" because the tool would dig into the surface.
Thanks in advance.
tc

9

G-Code, CAD, and CAM discussions / Multiple work offsets and Z clearance

« on: April 28, 2012, 09:52:39 AM »

With only G54, on repetitive operations my Z axis clears the work piece .5" and then goes up  when it returns home, providing plenty of clearance between the tool and the workpiece.
I've duplicated this code in order to run the same operations on G55 and G56.
The problem I am having is that when the Z axis is done with G54 operations, it drops down to the work piece zero point and then returns home before moving to G55.
This obviously provides no clearance when the tool is moving. I need the tool to go up and get out of the way when it completes the operations on one workoffset before moving to the other.

Here the code snipped between one work offset and the next one. What should I remove or change.
thanks.

tc

N4280 G1 X2.4652 Y.4739 Z-.2216
N4290 X2.4891 Y.4973 Z-.1881
N4300 X2.5125 Y.5212 Z-.2216
N4310 X2.5353 Y.5457 Z-.255
N4320 G3 X2.8941 Y1.475 R1.3827
N4330 G0 Z.5
N4340 M5
N4350 G49 G0 Z0.
N4360 X0. Y0.
N4370 A0.
(--- G55 Work Offset Was Added ---)
G55
%

N100 G20
N110 G0 G17 G40 G49 G80 G90
( DRILL )
N120 G49 T1 M6
N130 G0 G90 G55 X1.8102 Y1.0638 A0. S5704 M3
N140 G43 H1 Z.5
N150 Z.2

10

General Mach Discussion / multiple tools offset question

« on: April 25, 2012, 11:23:40 AM »

Despite setting and saving a tool off set( it's a shorter tool than tool zero), when Mach 3 goes from a drilling operation to a contouring, with a different tool,
the offset does not take. Essentially, the new tool falls short of its zero point on the workpiece.  I don't get it. 
For perspective sake, tool 0 is set at 0 in the offset table, and the tools preceding the countouring operation appear to work fine, since they all have the same length.  When I change the tool to do the contouring, with an offset of -.500( half inch shorter than tool 0) in the tool table, the program does not recognize it.
Mach 3 does know when it's a tool change.
Any help is greatly appreciated.
tc