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Based on the given information about the requirements and constraints I cannot advise anything and cannot tell wether it will be successful, clever or foolish.

My search terms would be: (without deeper knowlede)

lookup table
kinematics

Digging through the hal component list and look if I could convert the linear movement to an angle in the hal.
linuxcnc.org/docs/stable/html/hal/components.html

Greetings.

high resolution rotary encoders tend to be more expensive than a linear scale, so for a sine bar like arrangement I was thinking if a linear to angle system would benefit from. High torque, and high accuracy. At the cost of a very limited angular range.
 

Using MDI with python there's a 20ms delay between sending the command and the robot starting the move. There is also a 20ms delay between each MDI command i can send. So if i want to send 10 points to the robot it'll take 200ms to just send the commands.

This is far from ideal for a realtime application. Is there a parameter I can tune to speed up MDI?

Rod has a point about making sure you are using the right Mode. Assuming you are using Mode 1, it’s really odd to me that the power source is sending an arc ok signal when there is not even an attempt at a pilot arc. I know my powermax 65 (xp) will stop the post cool down flow and fire up the pilot arc. But also it won’t provide an arc ok signal until the arc is actually … OK.

It’s odd that it requires two torch on pulses to fire up after the cool down phase.

Are you sure it’s not in some other mode, like gouging or cutting expanded metal?

Also, I feel like this is vaguely familiar from an issue someone else had here. You might do some searching (if you haven’t already) of the forum, even though the search mechanism can be …limited…

Good morning friend, I know some shortcut keys for LinuxCNC, one day I will see if there is the possibility of creating a custom shortcut key and then I will post it here.



Keystroke Action Mode

F1

Toggle Emergency Stop

Any

F2

Power On/Off Machine

Any

`, 1..9, 0

Set Feed Override from 0% to 100%

Varies

X, `

Enable First Axis

Manual

S, 1

Enable Second Axis

Manual

Z, 2

Enable Third Axis

Manual

A, 3

Enable Fourth Axis

Manual

L

Select Jog Increment

Manual

C

Continuous Jog

Manual

Control-Home

Execute Home Sequence

Manual

End

Touch Off: Set G5x Offset for Active Axis

Manual

Left Right

Jog First Axis

Manual

Up Down

Jog Second axis

Manual

Pg Up, Pg Dn

Jog third axis

Manual

[,]

Jog fourth axis

Manual

O

Open file

Manual

Control-R

Reload file

Manual

R

Play file

Manual

P

Pause execution

Auto

S

Resume execution

Auto

ESC

Stop execution

Auto

Control-K

Clear background graph

Auto/Manual

V

Switch between preset views

Auto/Manual

Shift-Left, Right

Fast X axis

Manual

Shift up, down

Fast Y axis

Manual

Shift-PgUp, PgDn

Fast Z axis

Manual

@

Toggle real/commanded

Any

#

Toggle relative/machine

Any

Hi all,  im nearing the end of my retrofit build. I am wanting to use some keyboard shortcuts. Not for jogging! 

I want to be able to select individual axis for mpg jogging using a keyboard shortcut. Also select things like mpg reaolution. Is this possible? 

Thanks in advance 

LinuxCNC has two forms of safety. The first is to limit the maximum distance that the axis can travel, but this option only works if the home is started in the initial position, otherwise it will collide. The second form of safety is to have sensors for the start and end of the stroke and the initial position, with these three sensors it is ideal to guarantee safety. A third option is to configure the drives, some equipment has parameters to limit the current and thus not exceed the mechanical limits of the machine.

A simple (simplistic?) way would be to use the lincurve component to compensate for the non-linear rotational distance.  Your model also needs to incorporate a pivot at the ballscrew mount since the screw will swing as the B-axis travels.

I would also install a high resolution encoder directly on the B-axis so LCNC can use a PID to adjust for screw mapping and lincurve errors.

But yea, I'd also abandon this idea and use a direct drive motor or a roller cam gear - or even a harmonic with a brake.  Even more simple - a big gear with two pinions and two servos.  One of the servos is in position mode and the other is programmed in torque mode to oppose the position servo to take up backlash.

Now you have a THCAD 2 you can do more tests.
But normally, you would set the THCAD to use 1/32 frequency. This would alter your offsets etc accordingly. Make that change
Assuming a 10 volt range, apply a 9 volt battery to the THCAD  HV input. The flashing light should change frequency. Does it?
the voltage should be about  90% of your full volt range. Is it?
What are the calibration frequencies for your THCAD on the sticker?
Read the encoder velocity at 0 volt at rest and at 9 volts.
What are these readings?

Just a question ? Do you have those softwares at hand?
You might end up with five axis requirements and then looking at a hefty monthly suscription

Just get a new detector and use it, for what it was for . But... did it come with some sort of x-ray light source?
mmmh. Any lead west in the box?

How about a 3d scanner? Woud at least be more close to original function.

I see your point. I thought to use Autodesk CAM (Inventor or Fusion).

Also something like this was used by Centroid for their cylinder head porting and polishing machines. Except they used to turn the work piece rather than the spindle. In their newer design they claim that the b-axis is controlled by a ballscrew but it is not visible

I'll make some more tests with MDI and see how feasible it is.
Motion blending is a must have for us.

Hi

I am new to CNC and specifically LInuxCNC. I am trying to build something like this for my B axis except I use the ball screw to turn the spindle rather than turning the workpiece. So it is possible to write a math function to relate the linear motion to the angle of the axis. It is similar to the formula used to find the crankshaft angle when the piston has travelled x distance. Like this

But how do I enter this into LinuxCNC? I am ok with the math I need help on the implementation into LinuxCNC

If you read the QTplasmac docs, there is a link to a calculator to determine your settings.

I'm using the calculator from the PNCconf. 

SOS UPDATE:
Changed the THC to THCAD2 and change for a divided arc
Put the THCAD2 outside the plasma source in a plastic box.
Shielded only on THCAD2, in new cables. 

Made the changes that you recommend:
   

Results:
This worked a week, but it happens again. The arc voltage is on -45.

I can take more pictures, make video. If anyone can help.