Messages

161

Mach4 General Discussion / Re: Erratic Feedrate When Cutting Spline Lines

« on: September 27, 2017, 07:37:44 AM »

Chaoticone,
Your wizard Simulated with the Road Runner runs very well in inches.
I too use Metric mm and it is a bit time consuming to set up and test in metric, so I look forward to seeing it in Metric version.
When I engrave in Brass with a .05mm Radius Tapered cutter I do not want to exceed my G-Code settings of 400mm/sec this way my cutter can do multiple 12 hours cuts with no cutter damage.
So in your Wizard can you add a Maximum Velocity speed so when it writes the data to machine.ini it will replace all the higher numbers with this G-Code maximum?
It also appears from your explanation that the Angle is measured from the Back plane and not the Front.
So the 179 degree is actually a sharp point movement and a 1 degree is 1 degree less then a straight line.
On our 3D medallion which we carved recently I used 100mm/min on all angles on all 3 axis with the normal straight cut running at 400mm/min and they came out reasonably well viewed under a microscope.
Your method would reduce the cutting time and still obtain a good result and on top of that be able to increase accuracy with your tolerance option.
Looking forward to seeing the update in Metric with hopefully the G-Code Maximum Velocity inclusion else cutters will be broken.
Regards,
Mauri.

162

Mach4 General Discussion / Re: Erratic Feedrate When Cutting Spline Lines

« on: September 26, 2017, 08:54:49 PM »

Chaoticone,
I have made a quick test and have a few questions.
I have included a DOC file that has the data and graph.
Question why does the CV Feedrate exceed the Mach4 Motor settings?
Is angle 0 a straight line?
Why are the Feedrates higher on small angles and zero on the large?
Are the Feedrate the wrong way around?
Regards,
Mauri

163

Mach4 General Discussion / Re: Erratic Feedrate When Cutting Spline Lines

« on: September 26, 2017, 03:52:09 PM »

Chaoticone,
Yes that would be of interest to many of us.
Regards,
Mauri.

164

Mach4 General Discussion / Re: Erratic Feedrate When Cutting Spline Lines

« on: September 25, 2017, 07:13:47 PM »

dq828,
Directional change in CNC machining is a complex physics and mathematical issue.
If you had a machine with magnetic slides then directional movement would not be an issue as the table is held in a magnetic field suspension.
We do not have $500K plus.
As most of us have linear ball slides on Router Tables or V's with Gibbs on Mills we have to contend with a lot more issues.
The better the machine is constructed the faster you will be able to run it.
When a force (Y/Z gantry platform or X/Y table) is being sent in one direction like CV Angle 0 and then you want it to return back you have to stop that table smoothly or come to a complete stop before you change direction back.
The X/Y platform wants to lift off the table making the balls hit the rail guide and shake the machine.
A roller guide connected to the Y gantry and rolling on the bottom edge of the X table on both side would reduce this (hence a better design) or have linear ball rails on the bottom as well the side.
On the Mill the issue on the X and Y are the Gibbs on the V slide, too tight premature wear and tear on the slide and motor or the motor may not be able to move the table at all.
Too loose and the table ants to kick up.
Below are some Physics and Maths on CNC angle movement.
So you need to have the CV on the Angle 0 as this is the maximum shake angle.
Regards,
Mauri.

165

Mach4 General Discussion / Re: Erratic Feedrate When Cutting Spline Lines

« on: September 25, 2017, 04:04:50 PM »

dq828,
I change all angles 0 to 179.
We do fine engraving in Brass with the finish cuts being with .05mm Radius Tapered Cutter.
This means that we do not know all the angles, as it could basically cover all of them and braking cutter tips is not an option.
Performing a Simulation on the 3D image shows us when we have a good enough CV settings (i.e.) cut follows closely to the original G-Code.
If you know you angles you can modify the CV speed to suit.
Yes you can copy and paste pre edited or programmed settings in your machine.ini over the existing settings and save the file.
You can program in Lua on the Screen yourself a suitable program or modify the exiting CV wizard.

Machine shake:
Reduce F Speed
Reduce CV speed
Fix Machine to prevent kick.
Or use Exact Stop

Regards,
Mauri.

166

Mach4 General Discussion / Re: Erratic Feedrate When Cutting Spline Lines

« on: September 24, 2017, 02:02:42 AM »

dq828,
It looks like you are using a Router Table and probably have single one direction rails.
If you had rails also in the other direction it would stop any kicking "jerkiness".
So on some angles it probably depends on the direction of movement more X then Y making it Jerk more on the X axis than the Y axis.
You can slow down the F speed to compensate or reduce the CV settings.
Or if you can affix a Roller under the Router Table to stop the X axis kicking that would eliminate your problem.

Two was of setting CV on all axis.
If you do not change the Mach 4 Settings you could make a set of machine.ini with different CV settings.
You can manually edit the machine.ini in notepad make a Set 100 then save it as machine100.ini.
Then make a CV 75 and CV 50 and save it as machine75.ini and machine50.ini etc.
When you want to use a specific one your copy one into another directory and rename it to machine.ini and put it back inti Mach4 directory replacing the existing one (make sure you copy it back and rename it back to machine*********.ini.
When you make the changes in notepad do a search for say = 75 if only the CV angles are 75 and you want 50 then do a replace all.
Hope this helps.
Regards,
Mauri.

The other method is if you know Lua you could code it up on a Mach4 Screen to do it on the fly automatically.
Regards,
Mauri.

167

Mach4 General Discussion / Re: Erratic Feedrate When Cutting Spline Lines

« on: September 24, 2017, 12:25:36 AM »

dq828,
Yes, you are correct you have CV running, I did not fully read all your notes until now.
The slow down is the angles and the CV in action.
As you do not show us the exact full F speed I cannot confirm weather the CV is set correctly.
Please advise the F speed and the CV setting, the cutter type and size and the material type being machined.
With this info, I may be able to provide a more optimal set of settings to perform your job.
Using Exact Stop will do the task correctly however will take longer.
Jerkiness is also caused by going too fast and your machine is not built to handle these speeds and directional movements.
Regards,
Mauri.

168

Mach4 General Discussion / Re: Erratic Feedrate When Cutting Spline Lines

« on: September 23, 2017, 03:29:13 PM »

dq838,
You must use CV to reduce machine shake.
Selecting the correct CV will produce outcomes very close to your profile.
If your machining at between 400mm to 1000mm per min, set all the CV 180 angles from 0 to 100.
Regards,
Mauri.

169

Mach4 General Discussion / Re: Mach4 Axis Calibration...

« on: September 06, 2017, 10:10:03 PM »

gorf23,
This is my version of Ball Screw Calibration for Mach4.
Regards,
Mauri.

170

Mach4 General Discussion / Re: Mach4 V3468 cannot get it to shows Controller Plugins?

« on: September 06, 2017, 07:26:46 PM »

Igors Belajevs,
Inputs and Outputs in Mach4 Configuration work in conjunction with your Controller and are mapped to your controller card connection inputs and outputs.
Each Controller card manufacture I am sure has provided manuals showing the connections and in some case also provided a Profile.
Send an email to your card manufacture or look at what they have on there website for examples and documentation.
Also read the Mach4 Documentation.

If you are trying to connect Buttons that are on your Controller equipment to act the same as the ones in Mach4 Screen, then these apart from Mach4 Input/Output also require Signal Scripts to make them work.
If this is the case then you must read and understand Mach4 documentation on how to program in Lua and write the code in the Signal Script of the Mach4 Screen.
An example is provided in the documentation.

Always disconnect motors from controller when program testing.
 
Normally all those 5 items you have listed is controlled by the Mach4 Screen and should not require any action on your part.

Regards,
Mauri.