Small hole processing 20mm thick, Amada X1 (LVplus) 3

[jacobsonse]

Hi.
We are cutting 20mm mildsteel with some small holes size about 9mm and they are right size for about 3/4 deep then they get larger.
Cutting with 10Hz , Current control, speed 100mm/min gas 1bar focus +2,5 nozzle D24 1,5mm standoff 1.5mm

What should i do too improve the cut quality?

 

[laserdog]

I don't know anything about the X1 but if it's like the F1 we have I can show you what we do. Do you blast pierce the hole or use a ramp pierce?

 

[jacobsonse]

The X1 is a Amada branded Mits LVPlus.
Using ramp pierce, 2step

 

[laserdog]

 

[jacobsonse]

Are you cutting small holes at 30 in/min? Is the F1 power rating average or peak value?

 

[laserdog]

The main small hole we cut is .6 on the E3 cut condition at 27 ipm as far as the power rating it would just be a guess. We've been cutting 3/4 non stop for 4 weeks now and out of 145 parts per sheet we may have 2 bad ones.

 

[jacobsonse]

Do you have à picture of the cut on 3/4? How much tapper do you have?
We cut 20mm at 800-850mm/min depending on material.

We cut 12mm at around 1450-1600mm/min, is it close to how fast you cut?

 

[laserdog]

I checked this part and the difference between the top to the bottom is .005.

 

[jacobsonse]

What should i change to decrease tapper at the lowest 1/3-1/4 of the cut?

 

[laserdog]

I need to know a few things, your focus looks like 100, the feed rate looks like 39ipm would this be correct? I have never heard of a D24 nozzle so I don't know what size that is our nozzle is a 4.o WACS nozzle. Is you nozzle gap your standoff? and is it a 4KW laser?

 

[jacobsonse]

IF you look at II-VI catalog for amada nozzle page 19, part 2 goes into part 3.
There you have d24 nozzle.
Standoff is nozzle gap.
Speed is 31,5-33,5 inch/min for 20mm thick.
4Kw power

 

[laserdog]

I have no idea what your experience with cutting is so I will treat it as if you work with me. It looks like you have a few things I would adjust but you will need to do them one at a time so you can see if the changed helped. The first thing I would adjust is the gas pressure, I think you said 1 bar, we run at .5 so try that and see what it does. The focus looks high, you said 2.5 mm (.100) we run around 2mm (.08). This is just a few things you can try but the quality of the material is a major factor. Gr50 cuts so much better that A36 and the scale on the top of the sheet will also kill the cut.

 

[jacobsonse]

Gas pressure at outer contour is 0,9. Material ruukki laser plus 355mc, designed for lasercutting.

When we are cutting 25mm thick we have focus at 2.0 feed 625mm/min nozzle gap 1.0
Gas PR 0,7
So like you recommended lower the pressure and lower the focus as a start.
Getting some tapper with 25mm also.

The X1 use a highspeed powersensor for adjusting average power, so if we set power at 4000w at duty 80% were getting peak power at 5000w. Or 2500w duty 50%= peak 5000w
Is the F1 like this?

 

[jacobsonse]

Tested with lower focus but got problems when piercing and no better cut.
Lower gas pr with a little better cut.
Hole size at pic is 12mm. Not cutting small holes as good as in 15mm thick.

 

[evans1089]

With thicker material, we found that using a larger lead in with a radius gives a better hole.

 

[jacobsonse]

Cut some more today, changed to cutting holes with more standard cutting instead of low hz type cutting. Added more lead in and also added a small joint too get less burning at end. Holes at 12mm are good, but 10mm still have some adjustments.

How much do nozzle distance influence cut quality when using a dubble nozzle?

 

[jacobsonse]

Have cut some more 20mm the last days. Lowerd the nozzle high and reduced gas pr.
Speed 850mm/min gas pr 0,6 focus 2.0
Should i try too increase speed? Or do you think i should be pleased with the cut?

 

[laserdog]

Look at the curve of your cut line if you go faster the bottom may not keep up with the top so with your setup your feed is fine. You have a good quality cut that any customer will be happy with so run with it.

 

[jacobsonse]

Thanks for your answer. We cut a sheet for 4,5 hour today. Total of 180 12mm holes. No fault or stops.

 

[jacobsonse]

8,8 mm holes. Not much tapper. Front vs backside.
No problem make 1/8"G in it.[sub][/sub]