Amada FO3015 cutting .12 aluminum

[LaserLogan]

Hi,

I'm new to cutting with a laser and I am having problems cutting .12 aluminum with pvc coating, I am trying to to do a pre etch to burn the pvc away so i can cut it, but seems like the height sensor is not responding and the nose digs into the metal and does not burn the pvc in areas, I cut some 3/8 stainless steel earlier today and had no problem and the height sensor seemed to work fine with that. if anybody has some suggestions to check or try that would be great

We have an Amada F0-3015NT 4,000 watt laser

etch condition
feed rate 100
power 200
freq 35
duty 10
gas pressure .04
gas kind 1 (oxy)
nozzle gap .1

cut condition
feed rate 137.8
power 3500
freq 2000
duty 100
gas pressure .80
gas kind 4 (oxy)
nozzle gap .118

 

[JeanFreli]

Hi LaserLogan,

I'm new too but try to help you anyhow. The first thing I'll would try is to cut the 11ga(.125) without pvc so you can see if the problem is still there. If it is still doing it you might have to calibrate the sensing. It does that after they change the head of my machine. And if it doesn't do it you may have to revised your conditions for the pvc cutting.
In my opinion just like that you should be faster burning the pvc than cutting the real materiel. I start working next week and I'll come back with conditions cutting. I have a good idea but want to be sure. Maybe by the time some other guy(or girl) will give you good advice.

 

[b20vtechb]

I don't really see why you would need to pre-cut the pvc, it should cut just fine with it there.

I would suggest cutting the aluminum with shop air "gas kind 5" make sure you change all your piercing and edge conditions to match.
your nozzle gap looks really high for cutting i would change it to .025" or so.
If you are having issues with the pvc bubbling up on a pierce increase the nozzle gap in the pierce condition page to between .1 .15 and lower the pierce gas pressure to around .1 also.

also what lens and nozzle are you using? i use the 5.0 lens with a 2.0 nozzle for that material and thickness.

 

[tstc]

although im not familiar with Amada, i would suggest you need 'evaporate/burn' parameter more so than 'etch'
to evaporate the pvc, i would be using a standoff of about 5mm, run a negative focal, use N2 gas, and go pretty quick.

so maybe try....
feed rate 40000mm/min
power 400watt
gas pressure 3bar
gas kind N2
nozzle gap 5mm
focal position -3mm
laser mode CW (duty 100 / freq 0 <= is this CW for Amada??)

this should evaporate about 5mm of the PVC (2.5mm each side of the intended cut line)

just try to stand off high(nozzle gap) and go fast!!
this should keep the nozzle/ceramics/cutting head clean of burnt pvc.

 

[JeanFreli]

Hi LaserLogan,

I said I'll come back with somes parameters trying to help. Well here I am. I forgot to check for the film burning but like tstc said it should be very close. By memory it is about that. Just for frequence and duty I don't know what it is but soon or later I will discover.
I'll give you stuff for cutting but I don't know if the fiberlaser can be close of CO2. So it goes like that;
Power 2000 (You have more power available so probabely the luxury to speed up)
Cut height .0394 (1 mm)
Feed rate cut1-2-3 90-100-125 If you have only one speed use 125 in,min
Gaz N2
Pressure 18 bar try lower a bit if you want. That's the only pressure I kept from the Turkish guy because it work good
Lense 125 mm
Lead in cut 1-2-3 78-88-108 in,min
Nozzle 2
focal -4.5
Don't forget all aluminium cut need a little work after. If I have time I pass the dynafile or I send it like that to the guy and are happy anyhow. It is already better than plasma. I'm still working on all my cut just for experiment. But don't worry these worked great for me. Even the .250 is amazing. I passed too many years on plasma....love the laser.
Give me some news if you can.

 

[LaserLogan]

Thank you for the suggestions

I did not have much time to mess with the settings so I peeled the protective coating off and it seemed to cut good with good edge quality and looked like the height sensor was working. in my first post I had a typo on the nozzle height for the cut condition its actually .0118

I cut some 3/16 stainless after I finished cutting the aluminum and it had no problem cutting through the same protective film and the metal at the same time. It seems like the stainless stayed cooler while cutting which may have helped the pvc stick to the metal

I will have to try your settings for the pre burn to see if it will help, I don't know of any preburn parameters on the laser, if anybody knows what it is called or where to find it on an Amada 3015nt fanuc controlled laser

 

[LASERNINJA]

The last column on the right of the pierce page is where you input this information. There are three different routines to deal with vinyl coated material.
133
134
135
On the bottom of the screen there is a button. It says laser set or somthing like that. Press that and you should see where you can set the height for the pre burn. Closer to the material, hotter narrower.

 

[Chally72]

Isn't 0.0118" nozzle standoff extremely small? Also gives the machine less time to react to changes in sheet height.