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George M. Perzel
05-02-2012, 7:22 AM
Hi Gang;
What is the fastest you have been able to scan (engrave) with the Shenhui and still get good results? My top is currently set at 500 mm/sec.
Best Regards,
George
Laserarts

Mike Null
05-02-2012, 8:04 AM
One inch equals 25.4 mm or mm = .03937".

In this case 19.7" per sec.

Scott Shepherd
05-02-2012, 8:12 AM
George, how are you actually measuring that? I'm just curious. I've seen it mentioned before and always wondered how people measured it accurately.

George M. Perzel
05-02-2012, 8:35 AM
Scott;
I am going by the speed settings in the software-"vendor settings" determine speeds which can be changed. Machine comes with max limit set at 400mm/sec. I have measured it with a stop watch-30 passes back and forth over 11 inches yields 430mm/sec including decel and accel.
Best Regards,
George
Laserarts

Rodne Gold
05-02-2012, 10:08 AM
I have been able to get mine to 800mm/sec as a setting, tried 1000 but the steppers started protesting , at 800 it was actually SLOWER than 500mm on small engravings , didnt try on long passes tho , even 500mm/s is slower than lower speeds on small stuff - got to do with ramp up I suspect , high speed the head actually travels a lot more distance per scan pass on small stuff. I'm sure yours with twin heads has a lower speed limit due to inertia etc than a single head , but in the final analysis , yours is 2x faster anyway (2 jobs in one pass) :)

john banks
05-02-2012, 3:03 PM
We set our max to 800mm/s, but as above for smaller stuff the acceleration and deceleration make it slower for most of our engravings.

The problem with my 100W RECI is that I tend to use more power to suit the faster speed and if I go over 20% power the laser doesn't turn off neatly and splutters with a small after-fire which on some materials leaves a mark and nasty feathered edge.

If I can keep the power low and the engraving is wide then 800mm/s can be useful, but I hardly ever get this combination.

We're more interested in vectoring, and for that 50mm/s is our limit with a one third reduction in the acceleration speeds from standard which increases the time to do a job by about 25% but gives much less wobble on tight details, so eagle's claws look sharp, and the bars on fonts look straight rather having a sinusoidal wobble. These effects didn't disappear to our satisfaction until we reduced to about 15mm/s, so to be able to run at 50mm/s with effectively the performance of 40mm/s is a great compromise.