FOM2 3015 cut quality issue 1

[sparky4808]

Hi everyone. I just signed up for the forum, but have been lurking for some time. Lots of good info here.

I am having trouble identifying my issue here. 5/8 mild steel; the bottom half of the material (the whole way around the part) seems to be "washing out". it is a smooth cut but half way through you can see/feel a dip in the cut.

What I have done so far:
New internals and Externals installed and aligned by Amada. Ran leak check = good. Purged fresh laser gas 3 times. I can get the cut quality to worsen by changing conditions but I cant get it to cut any better than what im getting. Cleaned nozzle, replaced nozzle, cleaned focus lens, aligned nozzle centering, recalibrate height sensor.

I've been told it could be a material issue but I can cut good parts at the beginning of shift and then slowly goes bad. I don't believe the focus to be at fault because as I said, good parts do cut but not all day.

Any help is appreciated!

 

[sparky4808]

Another pic of part.

 

[RPosty]

Damn, we would be happy with that at my shop. 5/8" is tough. post your parameters, nozzle type/size, gas settings etc so the experts here can help you better. I am not an expert however, Questions I would ask is:
1. Are you seeing a drop in Power?
2. Is your Chiller maintaining proper temperature?
3. Does your Oxygen Tank have an evaporator to keep the lines from freezing (and more importantly the Valves)?
4. Does the same thing happen regardless of table location? (think Beam Purge)
5. are any of the external optics feeling warm to touch?


Did you get the internals from Amada or II-VI? I ask this because we were having some issues with a knock off Output Coupler from Design Research, rest of their internals were fine, but the output couple caused issues over time at full power (actually at 3800 watts, couldn't get 4000 with it.) Really gave us trouble cutting aluminum at end furthest from resonator. Got a II-IV output coupler, got steady 4K and distance issues ended as well as crappy cut over time.


"I am stuck on Band-Aid brand, 'cause they are stuck on me"

 

[sparky4808]

Thanks for the reply RPosty. I agree that they should be happy with that, but some of the smaller parts are a little more crucial for the fixtures they are welded to. Our plant has a high emphasis on quality parts from the beginning of fab to the final assembly.

1. No power puck so I cant really tell. commanding 4000w @ 65% duty so power output seems comparable.
2. Chiller is good
3. Have never had an issue with lines freezing...one question what is the average regulator pressure coming off the oxygen supply? I believe ours is running 150-175ish?
4. Same thing everywhere our operator has cut, with the exception of a random part here and there. parts 1,2,3 could be bad, 4 good, 5 bad, 6, 7...just randomly. its weird.
5. Everything seems to be cool.

Optics are all from II-VI. We don't have a power puck to measure actual power so I cant give you that info. PWR COEF is 1034...

I will have to get back to the machine and record all the conditions, i'll be back with that info this morning.

 

[Foostrap]

What is wrong with that cut quality? The edge quality looks fine.
By dip in the cut, do you mean it looks like a hourglass shape when looking from the side of the cut? Is that the problem? If so, that is usually material related. What grade mild steel is this?

You could try to cut it at medium speed settings (less power and less speed); see if there is any change.

You mention the parts are good when cut in the morning, but then go bad later on. Can you post a picture of both cut qualities next to each other, so we can see what you get?

 

[sparky4808]

Edge wise it is mostly great, just the defect halfway though. Hour-glassing would be the best description of our problem, except it starts at the middle of the material (thickness). I have suggested that it is material related but no one can seem to wrap their head around that concept. Its hard to pin it on that because of a few good parts coming off the same sheet.

Everything we cut on this laser is 1010 mild steel.

I have not tried dropping the power and slowing it down. If that would have a better outcome what would this tell me?

Unfortunately we have pulled off this part for the time being and are cutting smaller material until we can get it figured out

Thanks for the replies

 

[Foostrap]

If you cut it with less power (and slower) and that issue goes away, it would indicate the material cannot take the heat at full power; and therefore it is material related.
Is the angle of the edge the same in all directions? If not, your beam may not be coming down perpendicular to the plate (even though the alignment might be OK). This can cause some weird angle issues when looking at the side cut.

What's puzzling is that you say it cuts OK on some parts; then this problem shows up. When does that problem come up: after cutting for X amount of time (heat issue or stability issue); or at a certain time of the day (change in environment, paint or other chemical in the air); or in a certain spot of your cutting table?

Any chance there is another brand laser in your area; where you could do a sample cut (with same power)? And see if you get same results.

 

[sparky4808]

we have an older FO3015 we are cutting the same 5/8 material on at full power and it is cutting it perfect.
The "hourglass" is the same all the way around, as is the good edge. it all looks straight.

As far as when the problem shows up, it could be at any time. the air quality is the same all day so that shouldn't be an issue.

 

[JeanFreli]

Go back to your original parameters if they were working before and clean your focal lens again. What size of nozzle are you using?

 

[LaserEngine]

Sparky4808 are you using Wacs when cutting this and what nozzle diameter?
I'm using an Fo M2 myself and i get really smooth cut edges.
So here which i would like to know from you

Speed:
Power:
Freqency:
Duty:
Gas Pressure:
Nozzle diameter:
What kind of nozzle:
AC:

 

[sparky4808]

I was able to deem the issue as low quality material. I performed the 10,000hr beam purge unit service and still had the same result. was able to find some drop material (from a different supplier) and cut the same part, same program back to back on different sheets. 2 completely different cut qualities. hopefully they will find a new supplier from here on out.

Thanks for all of your posts and insight.

 

[Foostrap]

There is a lot of crappy material in the US; especially in the grade 50 mild steel. Way more than there used to be since some mills got bought out and now import their materials.