Chinese Laser Slow Speed Cutting Limit?

[Brian Leavitt]

On my Chinese laser (Ruida Controller, RDWorks 8) if I set the speed to 10mm/sec or less the laser will not fire. Is this normal or is there a setting I can adjust to keep this from happening?

[Jerome Stanek]

Try setting the Min laser power to 60% and see if that will work. I had a problem were if I ran at 5mm and the laser Max set to 80% but the Min laser power set to 30% it would not cut at any thing above the 30% . Once I changed both max and and min to 80%it would cut at any setting

[Brian Leavitt]

Thanks, Jerome. I've never messed with the min power because I didn't what it is actually for. It's always been set to zero. I'll try that out tonight.

[Jeff Body]

Try setting the Min laser power to 60% and see if that will work. I had a problem were if I ran at 5mm and the laser Max set to 80% but the Min laser power set to 30% it would not cut at any thing above the 30% . Once I changed both max and and min to 80%it would cut at any setting

Are you talking about on the laser's control panel or in the software?

[Kev Williams]

Just thinking out loud here; why would they set up a laser cutter to not fire the laser below a certain cut speed? Especially considering you can fire the laser with the machine stopped...

Seeing what my Triumph would do trying to cut thru 1-1/8" cherry with a 3" lens, I was down to 1/2mm/second and the laser was firing.

Regarding the minimum power settings:

The speed you enter is a 'straight-line' speed. When running certain curves (depends on the curve and the controller and speed options), the speed will slow down to help preserve high detail. Also, when cutting straight line objects, such as boxes, the laser must slow down before it reaches a corner to change direction, then accelerate back up to full speed after the direction change...

the minimum speed settings are specifically FOR these slow-downs, to prevent overburn in corners or overmelting slow curve engraving.

If you have a mA meter, you can see the min/max power settings in action: run a 3" square with the min and max power both set at 30%, you'll find the meter won't budge as it goes around corners. But change the min power to say 22% and run it, you'll notice the meter needle blip down briefly as it does the corners. Using the meter like this, y can also find which curves the min power setting affects and which it doesn't...

It takes some experimenting to find the right ratio, depends on what you're doing. When thru-cutting the min power isn't all that important, but for say, vector engraving rectangle borders on wood, the min setting is very important in getting the corners to match the rest of the lines. This pic is the first piece of wood I ever engraved on the Triumph. Notice the rectangle border is very overburnt in the corners. This is when I discovered what 'min power' was for. After tweaking, the corners looked like everything else. (but I can't find that pic!)

DSC02801.JPG

[Jerome Stanek]

It was the software that gave me problems. When you set up the cut go into the cut and adjust the min power there

[Brian Leavitt]

It was the software that gave me problems. When you set up the cut go into the cut and adjust the min power there

That was it! Cutting fine, now. Thanks again, Jerome.

[Brian Leavitt]

And Kev - thanks for the explanation. I rarely use the Chinese machine. Typically when I get the urge to make something for my car buddies. I haven't read up very much on the software, and pretty much just wing it when I want to run something. Far cry from the ULS and Epilog drivers I typically use. I have ordered a mA meter for the machine. I've been meaning to for a while. I want to set it up so I can run up to 100% power in the software without overdriving the tube. Just been lazy about it.

[Brett Winston]

On my Chinese laser (Ruida Controller, RDWorks 8) if I set the speed to 10mm/sec or less the laser will not fire. Is this normal or is there a setting I can adjust to keep this from happening?

I had the same problem. The fix is in the 'user' settings in rdworks. There is a minimum speed setting there. You have to then set your speed for 1mm/s over that to get the laser to fire. Sorry, I'm not in front of the software now but can take you through it if you like later.

[Brian Leavitt]

Thanks Brett,
I'll investigate this setting later. It's been working fine since I set the minimum power to match the maximum power. I've been doing a bunch of cutting at 5mm/sec without issue.