Hallo Jerome !
hallo Boardmembers !

I studied now for a while your very interesting blog as well as the forum and learned
a lot regarding the form-cutting programme built by you. Congratulation, it's great !!
Now I started building my own cutting machine using your programme modified to my
homebrewed cutting circuit. It works but unfortunately not as satisfactory as I expected.

My basics:
- Windows-PC running Win98SE at 100 MHz (an ancient device - I know -but
suitable for doing some experiments)
- Jedicut Programme 2.3.2 (newer versions do not run properly on Win98SE)
- Communication-Modus: CncNet98.dll activated (others do not work properly)
- external timer ( I tried several cycles e.g. 2000, 3000, etc.)
- homebrewed cutting circuit with AVR-microcontroller doing step
preparation - bi-polar stepper motors

My ajdustments:
Options / Machine:
Nb mm/pas 0,026 (1,25mm/48 full steps)
Vitesse de Découpe: 50
ca. (mm/s) 1,00
Vitesse de Découpe: 20 (rapid, fast)
ca. (mm/s) 2,36
external timer 2000 cyc

My results:
"manual engine control":
slow: measured elapsed time 1,00 mm/s >> (corresponds exactly with Options/Machine)
fast: measured elapsed time 2,36 mm/s >> (corresponds exactly with Options/Machine)

But in a "circle of cut" (very simple example) there appear unexpected deviations in measured elapsed time !!
Step 1: 100 mm horizontal movement ("Horizontale") - SnapShot_3.jpg - fast
Step 2: "Extrado" of profile (depth 100 mm) - SnapShot_2.jpg - slow
Step 3: "Intrado" - " - - SnapShot12.jpg - slow
Step 4: 100 mm horizontal backward movement ("Horizontale" - RAZ Compteur) - SnapShot.jpg - fast
( For reference see enclosed sreenshots taken from running program).
Measured elapsed time:
Step 1: ca. 2,36 mm/s >> (corresponds exactly with Options/Machine)
Step 2: ca. 0,72 mm/s ???????? >> 1,0 mm/s expected ????????
Step 3: ca. 0,72 mm/s ???????? >> 1,0 mm/s expected ??????????
Step 4: ca. 1,70 mm/s ???????? >> 2,36 mm/s expected ??????????

Please advice how to overcome and solve this problem

regards / Hans-Peter

Hello !

Thanks for you feedback. I don't know that Jedicut release after 2.3.2 don't work on Windows 98 SE. I will take a look at this.

I think the phenomenon you describe is normal.

In Jedicut's settings, the frequency of timer is only used to estimate maximum speed for each stepper. But when you are doing a cut, you can't have these maximum speeds.
When your a doing a move, you can check "smooth" checkbox. If you check it, and if you want to do a movement of 10mm, your steppers will turn like this : 1 step on X1, 1 step on X2, 1 step on X1... Speed is divided by 2.
When you are cutting profiles, "smooth" option is mandatory for successful cutting, and you can't uncheck it. At this moment speed can be divided by 4 or less...

Do you understand ? It's difficult to explain this phenomenon in french, so it's very hard for me in english

Hello Jerome !

Many thks for your prompt reply and your detailed explanation.
I'll do some further investigation in order to fully understand the basics of "move", "cut" and "smooth" and their relationship.
Then I'll contact you and the forum again.

Have a nice day / Hans Peter