Keep losing nozzle center

[sparky4808]

Amada FOM2 3015NT keeps losing its nozzle center. We are going through 2-3 nozzles a day. New internal optics and external alignment is dead on. Beautiful mode shot and great power puck reading. My operators claim to have it centered then after time it gets off. any ideas?

 

[LASERNINJA]

Are there any signs of dragging on the nozzle? Is it possible the gantry is loose? Or, the cutting head. Post a picture of a toasted nozzle?

 

[RPosty]

I would watch them to see if you get any clues. we have a guy who likes to let the shuttle standoffs droop, slug comes up and head wacks it.

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

 

[b20vtechb]

Have you tried checking the tape shot in more then 1 spot on the table? Sounds a bit like an external alignment issue to me. but i guess something could be broken/loose as well

 

[laserdog]

You can have what looks like a perfect shot but it’s bouncing off the side of the nozzle. Put in a 4.0 nozzle and align it before you go to a 1.2 or 1.4 that way you know it’s perfect. Also make sure when they do the alignment to take as much of the tension of the set screws before they do the final shot. One of my operators would crank on the set screws so in time the alignment would get pushed off by the set screw with the most tension. So it’s real important that the set screws be tightened but only after the alignment is dead on.

 

[sparky4808]

Did a 4 corner cross hair burn and it came out good, so I know the external alignment is dead on.
I did pull the cone and check all the gas/air lines and it felt like one of the quick connect fittings may have been loose. I pulled them all off and re-seated them just to be sure. it has cut pretty good for a week now so will keep my fingers crossed.

Now that you mention the screws for the alignment they do feel kind of tight. I was having trouble getting the nozzle centered because my Heenie (the red bullseye when shutter off) was never coming out right. I re-aligned it and all was good. but then the screws were getting tight. I might back them off and do another tape shot with a 4.0 and then with the 1.4 as suggested.

thanks for the replies everyone, this is a great forum.

 

[LaserEngine]

Are you getting slits inside your nozzle?
In that case check if the nozzle is colliding during cutting with any parts standing up.

 

[RPosty]

if the screws are getting tight because they are maxed out maybe the spring loaded beam delivery is not seated all the way back true. if it is not perfectly straight and 90° from the gantry, when mode is centered through it, you will have a hard time centering the nozzle because beam is other than perpendicular to the work surface.

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

 

[laserdog]

If you had a hard collision with a part the bracket itself may be bent or something may have fallen behind the bracket. You can check this a few ways but the easiest way is after you do a nozzle alignment. Remove the plate that holds the cone down and look at the gap between all 4 set screws and the cone. If the cone is pushed to one side you have a problem so you might want to check the Z axis with a dial indicator.