Setting list for cutting materials?!?

[Matt Chivers]

Hi guys, We picked up our machine on Friday and we are very impressed with it, we are very excited about what we can do with it. I have read on this forum that there is a settings list for speed and power of cutting/engraving?!? any chance some one could email this to me please???

Many thanks,
Matt.

[Matt Chivers]

Hiya Dave,

It would be great if you could post them. We just need a starting point for us to go from on our ls3020 Pro.

[Spooky]

Board blew up, I just had to re-register

Will get the list up asap Matt

best wishes

Dave

[HPCLaser]

Hi Ls3020 pro....
3mm Px speed 6-8 depending on cast or xt
5mm Px speed 3-4
8mm px speed 2
1.5 mm laser ply 10-12
3mm laser ply 4-6
3mm MDF 4-6 depending on brand/density
Card 10-20 depending on thickness.

Engraving on this model max speed 200 scan gap 0.075 is good
Power to suit as this model is on rheostat power control (Knob)
Regards Chris

[johnb80]

How do you arrive at the correct speed / power combination? Presumably as speed goes up so does power? why would you want to reduce speed and power? does slower and lower power give a better finish? Why would you want to use anything less than full power when cutting?

Regards - John

[Spooky]

Hi John,

If I use 60 watts on a piece of paper im going to have a very hot machine very quickly and the wife running round to find the fire extinguisher

Joking aside, It's about dwell time and material deformation / immolation.

Laser ply (3mm) will cut cleanly and leave a less noticable burnt edge at a lower power and lower speed.If I pumped 60 watts into a piece of 3mm ply the actual cutting point will become carbonised very quickly continuing the cut into or through that carbonised layer takes more power hence more dwell time at the infinite point of contact between laser and substrate.

If you can picture whats happening at the cutting point in 3d.

The beam strikes the surface of your material and vapourises it then continues into the surface to "cut" through, as the cut depth continues beam scatter is going to mean you are still aplying radiation to that first surface so causing burnround or scorching while the beam penetrates. Even though the beam is travelling at a theorectical 186,282 miles per second it is not actually penetrating at that speed so scorching of the first surface has to be a consideration (on wood).There is an optimal point of time/power where increasing the power actually reduces the efficiency of the cut (Newtons law of deminishing returns)

The best way is to use the most effective beam contact time taking as many factors into consideration as possible.

Tube Life,
Heating of the cooling system,
Material damage,
Expunged radiation (hell it all has to go somewhere)
Input energy requirements,
Material flashpoints / burn temperatures (that's an expensive bit of kit to set on fire)
Machine wear (why go at 100% power and 100% feed all the time? those slideways do wear eventually)

Short version I guess is when I light our open fire at home I don't use a thermic lance, I tend to opt for a box of matches

best wishes

Dave

[johnb80]

So in general, if time is unimportant use the lowest power possible to get through the material cleanly at a medium to slow speed?

J

[Spooky]

Yup that just about covers it John,

rgrds

Dave

[silverstreamdesigns]

I agree! Where possible i got through thicker material in several cuts. Providing there is no tendency for the material to move or curl (has happened with some thin plastics!!!) this generally gives a good result!

I try not to let time be an issue - I keep a few other tasks to hand when i can!

[RebeccaCowley]

So if the power for the LS3020 is operated manually by adjusting the ampmeter dial, do you still need to enter a percentage in the box on newly draw or is that irrelevant?
What is the ideal power and speed to cut through 3mm Perspex and to preserve the machine?
If this is drastically out do I need to adjust the alinement of the laser to get better cutting results?
Also how do you improve the quality of the edges so they are not bumpy?

A lot of questions, I know, but I just don't want to damage the machine!

Rebecca