Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: fyshious on November 08, 2020, 05:02:53 AM

Title: Laser not cutting on axis
Post by: fyshious on November 08, 2020, 05:02:53 AM

Hi.
My laser has trouble cutting cleanly on the X axis. The Y axis is fine but need to make one or two extra passes for the laser to cut all the way through.
I am using a 7.5W (optical) diode laser with a fixed focus.
I have carefully aligned the laser head in the vertical and have tried some adjustments with focus but no improvement.
Is this caused by the laser dot maybe not being a perfect circle? The laser is Chinese and I can't be sure of the optics in it.
Hoping someone out there might have experienced this before and have a fix.
Thanks

Title: Re: Laser not cutting on axis
Post by: Graham Waterworth on November 08, 2020, 11:22:56 AM

Rotate the laser body 90 degrees and see if the error swaps axis, do not change the focus though so keep it at the same height.

Title: Re: Laser not cutting on axis
Post by: fyshious on November 08, 2020, 03:48:01 PM

Thanks. I will give that a try

Title: Re: Laser not cutting on axis
Post by: fyshious on November 09, 2020, 01:11:41 AM

Yes, the problem moved with the laser head so that means the laser dot must be distorted, a line instead of a circle.
Annoying but I guess there is no way to fix that.
Thanks for your help

Title: Re: Laser not cutting on axis
Post by: ZASto on November 09, 2020, 03:38:08 AM

If you have a line then your laser is out of focus.
Move your laser up/down or move your material accordingly.

Title: Re: Laser not cutting on axis
Post by: fyshious on November 09, 2020, 05:32:48 AM

Tried that. Got a small improvement with a shorter focus but not able to completely eliminate the problem. Given that the problem moved from one axis to another when I rotated the laser head indicates the problem is mostly with the laser head.
However I find keeping the lens clean helps a bit. It gets dirty quickly.
I have heard of compressed air being used on the cut but not sure how to set that up or if it will have any effect.
Does anybody have any ideas?

Title: Re: Laser not cutting on axis
Post by: Graham Waterworth on November 14, 2020, 01:02:57 PM

There are lots of K40 laser videos on youtube about using air to keep the cut clean.

Title: Re: Laser not cutting on axis
Post by: fyshious on November 14, 2020, 05:32:14 PM

Thanks. Checked a couple of of them. Seems to work so I got myself a coolant tube that I'll mount on the laser.
Watch this space.
Cheers