Messages

2621

General Mach Discussion / Re: Newbie Help Please to a Stupid Question about Feedrates

« on: June 09, 2012, 08:11:09 AM »

There are some canned cycles that can be found in Members Docs.
RICH

2622

General Mach Discussion / Re: Newbie Help Please with Tool Offsets

« on: June 09, 2012, 08:07:46 AM »

Why the Hell do they say it's FREE

Most software allows the user to try t out and see if it's right for them. There are usualy some kind of restrictions though and one should read the info to see what they are. Cost's time and money to develop software. Nothing these days seems to be free other than the individual
donated time of outstanding folks helping others on this site......

For LazyCam there is a manual and has all the info you need on using it for milling. Just draw your desired profile in CAD, offset the profile to suite your cutter diameter in CAD, export as a version 12 dxf, import to LC, clean the file, select the profile, define the depth of cut,
post code to Mach or save as a file, don't do things like trying to cut a arc with a cutter bigger than the arc, ect, .....read the manual,
have fun.

There are numerous CAM programs out there, each is different and costs vary, once you pick what you want you pay the price.

RICH

2623

General Mach Discussion / Re: z axis moving up

« on: June 07, 2012, 11:02:21 PM »

dray,
- I wanted to eliminate the power supply as the culprit by only only using it's power to run a single axis. So no power is being used by
the other drives.

- To eliminate the mechanical influences we are looking at pulses. Since you can't electronicaly count the pulses we are doing it
indirectly via a marker. It is not absolute as if you were using a counter. How well you can interpret the number of pulses is dependant on
the visual indication. I already explained the intent and you can measure form a simple disc.

- As said only move in one direction. NOT NOT back and forth  or  up and down.  I am isolating the influence of different rotor positioning
and want the movement as simple as possible. Changing direction can require additional pulses or even skipping which you cannot account for.

Once you have a base to relate to, by that I mean, the measured results of just moving in one direction and a comparison to moving in the the other direction. Then you can change some things, only one at time,....... to see if something makes a difference.
- swap drives, pulse duration, active settings, etc.
All of this imust done in a very disciplined way.

RICH

2624

General Mach Discussion / Re: z axis moving up

« on: June 07, 2012, 07:07:44 AM »

 dray,

I only test 1 axis at a time.

Please disconnect  the cables from the x &y  or diasble the drives when running the test as you only want power going to the Z axis.
You are cycling back and forth, dray. That is not what i want you to do. Only move the axis in one direction and before you do that, you make a move in the z to position the rotor for the direction you are going to move,then zero the Z and have the marks alligned.

 
RICH

2625

General Mach Discussion / Re: z axis moving up

« on: June 06, 2012, 06:59:42 PM »

dray,
Only one axis running, namely the Z for the testing. Later you can swap the axis by using the X and or Y drive in place of the Z.
The X & Y should not be run while doing the test because of the inadequate power supply you have.  We are trying to isolate the problem from other influences. You don't do a loop back and forth / up and down, but should first see how the number of pulses / indication in one direction is as compared to the number of pulses in the opposite direction.

Pulses .....one pulse sent to the drive is equal to the resolution in terms of linear movement. So 1/25600=.000040" of "possible" linear movement. Each move per pulse can and will vary some from each other  and it can take more than one pulse to change the rotor position, etc. The rotor of the motor requires 200x 8= 2000 pulses to turn it one revolution. So 1/2000 x 360 deg=0.18 degrees =10.8 min which
is the approx equivilant of .0094" of circumferential movement on a 3" disc. So if the scribe line / mark was .005" wide ( a razor blade cut) you
would see the rotor rotate  by one mark.

RICH

2626

General Mach Discussion / Re: z axis moving up

« on: June 06, 2012, 12:03:26 PM »

dray,

I have it run a 50 cycle test to move up .0625"

So you moved down and then up some distance just to remove any backlash, and then,  you did 50 consecutive movements of .0625"  for a total up movement of 3.125" up?
And the result was that in the total movement you were off by 0.004"? 

RICh

2627

General Mach Discussion / Re: Need Encoder for threading

« on: June 04, 2012, 06:45:36 AM »

Jim,
I also would not recommend a stepper motor to be used on the spindle for threading.
The single slotted disc works fine. I use Halls affect for the index. It will be more expensive than a OPB but it suited my needs better
for mounting.

RICH

2628

General Mach Discussion / Re: CamBam export g code into Mach3

« on: June 03, 2012, 08:09:10 AM »

Right click in the Cambam graphics area>Machining  >Generate Toolpaths and then the same but select Produce Gcode to save the file.
Open the saved file in Mach.
RICH

2629

General Mach Discussion / Re: z axis moving up

« on: May 31, 2012, 04:16:10 PM »

Have you got a citation for this RICH?

Ian,
Nope. Just a ball park number to make a point.
RICH

2630

Show"N"Tell ( What you have made with your CNC machine.) / Re: Constructing a Low Profile Tool Height Setter.

« on: May 31, 2012, 06:44:15 AM »

(but the accuracy of micro steps are a long standing point of discussion).

My testing has indicated that it can be influenced greatly by the motor. All depends how the Earth and Moon
align given a place in orbit.

So you may want to try a number of locations along the rotation and take an average.

FWIW,
RICH