Aluminum Cutting? 3

[vladz21]

hi, now my LC2415 A# NT laser is fully operational thanks to the help of @laserninja and @foostrap, I already start cutting mild steel and stainless.

quick question, why I cannot cut in aluminum 1mm thick, and I even can't pierce it! I use different method already, ( changing the focal lens, change the nozzle I even use double nozzle, then the different cutting condition, I even reach full power, and wont even etch?)

did I missing something? or problem with parameter? I been working on this for the past 3 days and it really hard to understand why?.

thanks, any input might help, and appreciated.

 

[ausman]

Check your focus, you will probably never actually etch 1mm Ali on that machine, you will burn the optics & bellows from beam reflections.
Use the shortest focus lens you have.
the beam will bounce straight off the sheet if the focus is out too far.
Pierce the sheet at pressure 0.2mpa & cut at 0.8mpa, 2mm Nozzle

 

[vladz21]

hi, ausman,
thanks, can I ask what do you mean buy the shortest focus lens, if I understand right? you mean the 5" and 7.5" focus lens right? right now here's my cutting condition. and I'm using 5" focal Lens 2mm nozzle.

 

[ausman]

Correct, we use 3.75" for most our thin material, but 5" works well too.
Try pierce Pwr 3600, Freq 50, Duty 80, pressure 0.2,

 

[vladz21]

hi, ausman
thanks I will try it now,

 

[vladz21]

hi again,
It didn't work, it did not pierce the aluminum, no matter how i played the condition,

 

[ausman]

Need more information, what's the background on the problem?
Is the problem new, has the machine just been put in, are you a new operator?
can you cut MS & SS ok?
What can you tell me.
Ta

 

[vladz21]

sure ausman, the problem is just that i cant cut to aluminum, and yes i can cut SS and MS cleanly, actually im not new at laser amada, i begin operating since 2002 til 2006 then continue at 2008 until now, i have a few minor knowledge in troubleshooting, last month i just change my IF Board, replace my sensor power and PSU,and i du also the alignment of the bend mirror only, i also change the oil for VPump and Turbo Blower, some minor staff, this problem is new for me, but when i came here at this company, i able to cut aluminum way back 2008, but since we don't usually do aluminum, only now due to a project came in, i make sample 50x50mm square sample for getting the right condition for ss and MS. only this aluminum that i cant understand sir,

 

[ausman]

Check your focus again, on your other post the B Axis travel when you run your focus program seems too large.
If your focus program only did 10 cuts and you start at B5.0 & ended at B15.0 that's incrementing
1mm per slit. It really needs to be 0.2mm per slit.(you might be a couple of mm out)
not sure if it makes a difference on your machine, did you check that the aluminium setting is on in the cutting data page?

 

[SGAFFNEY]

In the cut conditions you posted it shows an initial frequency for piercing of zero. Zero is not a valid value for frequency so I don't know exactly what that will do, but that needs to be corrected to start with. Since the duty cycle it set to 100% the frequency is not that important, but does need to be set to a valid value. If I remember correctly valid values are between 5 and 2000. Try 1500 and see how it works. Regarding Ausman's comment on focus, it may need to be tweaked, but if you can cut both SS and mild steel well it should not be off far enough to prevent you from piercing this thin alum although proper calibration of focus position is absolutly critical to getting to and maintaining proper cutting results. The numbers for cutting look a little off to me as well, but lets get it to pierce and see what happens. What wattage is your resonator (?3000?) and is your cutting feed rate inches per minute or millimeters per minute?

 

[jjl1210]

If you really want to test it change the M102 line to stainless so act as if you cutting stainless because they are so close to the same setup it should at least pierce. If you can get the Aluminum to cut under stainless condition you have something setup wrong in the aluminum cut condition.

 

[Foostrap]

What is gas selection 3 on your machine? Oxygen, Nitrogen, Air?
Normally 1mm alu will pierce with no problem with nitrogen. But since you have trouble, maybe try to pierce with oxygen. Oxygen will give you added energy to pierce through.
Also, what is the unit of the gas pressure in your parameters?
If the speed is 500 inches/min, that is probably too fast at 2000W. Try full power.
If the speed is 500mm/min, that is way too slow. It should at least cut through, even if you didn't have a good piercing.
Using a stainless cut conditions as suggested by jjl1210 is a good idea. That'll narrow it down a bit.

 

[vladz21]

hi everyone thanks for the input,

hi ausman,
my focus did 21 cuts that start at B5.0 then B5.5, B6.0 and so on, end at B21.0, and yes i did check the cutting data in amada.

hi SGAFFNEY,
yes i did make it zero and i also try 2500, 2000, 1500, 1000, 500, 200, 100 and down to zero, i already played it but seem its not working at all, my resonator is C3000D and my feed rate is mm/m. and i absolutely agree that if i can cut at MS and SS it should be easy to a thin alum, right?

hi, jjl1210
i did try cutting the alum in Stainless cut condition, it did nothing, its the same it did not pierce at all, i try in 1mm, 1.5mm and 2mm cut condition for stainless.

hi, Foostrap
i already try the 4 for nitrogen, 1,2,3, for oxygen and 5 for air, the unit of gas pressure at piercing is 0.2Mpa and 0.80 Mpa for cutting, and i did intentionally reduce the speed to 500 mm/m so that i can see if it will penetrate i also try making the Pwr at 3000, but seem I'm out of luck

 

[ausman]

When you used the SS settings did you test cut an SS part then immediately try the same on a piece of aluminium without changing anything?

 

[vladz21]

yes, i did cut the stainless without changing anything, and the cut for stainless does not change,

 

[ausman]

Strange, I will ask a bunch more questions

Did you see any evidence that the beam is actually coming our of the head and bouncing off the surface?
Silly question, is your lens upside down?
Are you using a single point nozzle?
Can you please test again with a nozzle gap of 2.0mm
Are you getting a burr free edge on SS?

 

[vladz21]

i know right? yes, i can see the beam coming out, and if I'm not mistaken the focal lens with the curve like humps was on the top inside the lens holder, this is what you mean upside down right? and yes, I'm using single point 2mm nozzle, I'm getting a burr like it can be remove by touch and it just need a little adjustment since in MS there is no trace of any burr or dross, when i cut it,

and heres new progress, i able to pierce it and cut a little, maybe around 10mm, then the beam bounce back again, and i try it 5 times it has the same result.

heres the condition:

 

[ausman]

Correct convex come at the top.
with the sot burr adjust your focus up 0.3mm then test cut, if it improves adjust it another 0.3mm & keep doing so until either it gets works or the cut is acceptable.
If you still have the reflection problem then try & watch your power meter & see if the power is dropping off when cutting.

Are you able to cut SS all day without issues?

 

[jjl1210]

I see a few things I don't like first of all I pierce and cut with the same gas kind because if you don't purge the line between the two you will have issues. The nozzle gap on the pierce is way low it should be close to 1.5 so you don't wreck the lens.

 

[vladz21]

yes, I have no problem cutting ss and MS everyday, and I will try what you suggest, hope it works, thanks ill up you after the test.