Cutting a circle with a lead in perpendicular.

[stivemaster]

Cutting a circle with a lead in perpendicular. The strange thing is that this leads to the execution of only the lead in and skipping the circle code !!!
This is a huge bug. Because there are cases where no other type of lead can be used in - it is plasma cutting of holes in material over 6mm thick and gas flame cutting of holes in any material.
When can this annoying bug be removed as soon as possible?

[cncdrive]

Full circle?
no, that is not a bug, it is a matchematical problem. Was discussed in details on the forum earlier...

[stivemaster]

Mathematical Problem !?!!?! Problem in what math is that? How is it not a math problem in other math systems, but is it a math problem that you use? I have read some time ago in your forum "your search engine is not working properly" but I can not find the topic again where the problem was commented on as being insignificant.
Imagine, however, that you pay to use a product, and he can not do the job he is told to do !!! Then what does your client do?

[cncdrive]

There is only one math system in this world as far as I know.

The problem is when there is a full arc or a very close to null arc and then there is a syncronisation of the coordinates between the controller and the computer which syncronisation is required for example if a macro is exacuted.
Then due to numbers mathematical representation on computers the arc starting point may differ, it might be just 0.0000001 or even smaller difference, but mathematically as how arcs are programmed on CNCs that can change if it means a full circle or a null circle. So, this is a math and number representation issue, not a specific UCCNC problem or bug, it exists on other control systems also...
The solution is to possibly not call anything between arc startpoint and arc code or to not use full circles, but ask the CAM program to do half or quadrate arcs. Most CAM programs have this option exactly to avoid this type of problem on the control side...

[beefy]

Stivemaster,

to get around this problem, in Sheetcam put a negative overcut value of -0.01

Then the circle is not complete and will have a definite starting and ending point. For plasma cutting you won't even notice 1/100 mm

I just tested it in Sheetcam and generated the gcode. The circle started at 150.00 and ended at 149.99

[stivemaster]

Hello beefy, "overcut value" you mean lead out?

Nothing logically exists in what you write CNCDRIVE . This problem does not exist in either Mach3, LinuxCNC or even the GRBL. This is a bug of your interpreter who does not follow the definitions of RS274 and does not execute motion when not for given donated X and Y only I and J.

[ger21]

Why does this only seem to happen with plasma users?

[cncdrive]

It does not happen with plasma only, it is a general problem, but can be seen with plasma users mostly, because they are who switching things (THC on/off, arc on/off, THC delay on/off etc. macros) before full circles and so the syncronisation of coordinates happens right before the arc start and that causes the issue.

[beefy]

Stivemaster,

when you are in a Jet Cutting operations pop up box in Sheetcam, you'll see an entry box called "Overcut". If you entered 3mm in that box, the torch would travel past the original start point by 3mm. In your case it would be 3mm past the start of the circle before leading out (if you have a leadout).

Gerry,

it hasn't happened to me (yet ). I'm 100% plasma with a little bit of using my plasma table to drill circuit boards.

[stivemaster]

This is not true, I explained in my previous post what the problem is. I have to upload a file code to see this. The inclusion of THC does not happen when the circle starts and when the speed is appropriate - or over 90% !
Additionally, you can not blame the use of the codes you have allowed for the performance of your interpreter!
What you have never thought about is that plasma cutting - obviously, a large number of customers need you and other than synchro-acting codes that you started to create for everybody.
There should be only M10 and M11 that are quite sufficient.
Pay attention to the next sentence!
Just change the plasma profile so that the interpreter will trigger the M10Q255 only if the speed is over 90% of the last set !!!
This will eliminate the problems that currently exist, even those that are created by CAM programs like SHEETCAM, for example.
If you do something like this, you will overtake all developers of plasma controllers in your price class. On the other hand, our company has launched our THC controller, which works extremely quickly and precisely, and does not need any attention at work. After the initial PID settings on the Z motor, you may forget that it exists!
Without any commercial interest, I'm ready to work together on what I wrote to you if it is of interest to you.