View Full Version : need help: slanted engraving / cut lines. Need settings for Shenhui SH350

Nils Fromm
05-07-2014, 11:21 AM
Hi everyone,

I have a Shenhui SH350 50W CO2 laser.

Can someone please send me a save-file of the vendor settings, or screenshots of the x and y axis settings (as in my attached pictures), so I can set the correct parameters?

Info on my machine:
Shenhui SH350
50 W laser
300 x 500 mm work area

Motherboard: RDC6442G (EC) (white color enclosure)
Motherboard Software versions (as displayed on built in screen when booting):

Stepper Motor controllers: 2M542-06 (black boxes)

PC-Software: RDCAM V6.0.37 and RDCAM V8 (makes no difference which one is being used). PC's used with Win 7 Pro, Win 7 Home, Win XP, no difference

the challenge is that the engraving (scanning) runs sideways, the higher the laser power setting is. At 12% power, it runs straight down, at 15%, there is an offset of about 1.5mm over a length of 15 cm, at 60% power, this offset is massive, and so on.
Attached a picture with 15% power setting on the engraving (the clean one), and tests with higher settings (the one that is engraved all over), so you see what my problem is.

I had the suggestion to activate the "PWM rising edge valid" option in the vendor settings on both x and y axis. This initially resulted in the slanting to go right to left instead of the typical left to right. Once this was changed again (only 1 axis is affected), then there was either no change or the laser head engraved the same line over and over.

In general, I believe the vendor settings are all messed up, or the controller box is broken.

Also, sometimes while cutting (vector based), the cut lines do not overlap on side-by-side boxes, even though they should. One line is offset by about 2mm comparred to the other. I spent about 3 hours yesterday with the belts to get this (more or less) right. a LOT of trial and error.
I now have it at the point where most lines overlap, and a small circle of about 2mm looks like a circle and not a flattened egg.

something else i realized on curves / triangles not being closed right was that the head moves from one spot to the next before cutting again, and that was where the error started. So i drastically reduced the idle speeds, acceleration speeds, max settings and so on. now the head moves very slowly, but it helps on the positioning.
If I have these speeds set to normal values (or as they were), the machine shudders quite a bit when moving the head around, which i believe is the reason for this.
So I can kind of work at the moment, but extermely slowly.

So if someone happens to have a machine with the same motherboard (and version), etc., it could solve my problems, if yours is working properly.

thanks for your support,

best regards from Germany288887288888288889288890288891288892

Martin James
05-07-2014, 12:43 PM
Hi Nils. I am not very versed at the settings, but in the first picture the minimum power setting is set to 2%. If I understand correctly how a glass tube operates, It might need more power to fire than 2% I think mine came set at 15% for the minimum.

Cheers marty

Clark Pace
05-07-2014, 5:20 PM
Hi. I just got mine, and it does not seem to have the problems you are having. i will see if I can view the vendor setttings.

Nils Fromm
05-08-2014, 8:05 AM
@Martin: thanks for the tip, you are right. Mine starts firing at 12% power. But this setting is just the minimum anyway, doesn't change my issues.
@Clark: I would greatly appreciate it! At the moment, I actually think it might be that one of the stepper motor controlers is half-broken :(