JL1 laser - from the sale in 2022

[orob]

Summary

It homes, then drives into the Y axis for a while, but it will run gcode ok and it thinks X0 is on the right. That move doesn’t appear to be damaging anything, but it is annoying and I’d like to fix it.

Background

Back a couple years ago, I picked up the JL1 laser off amazon for like $75. It sat for a year. My friend borrowed it last Thanksgiving and made some Christmas gifts with it. Before he took it, we flashed the board with GRBL and he used lasergrbl to run it. It worked fine. I bought a lightburn license for it. I just got it back last week and I’m trying to use it today… and it has a homing “issue.” All the commands are from the lightburn console, so the usb and communication is all working. Below are the machine details.

when powered on it reports:

Grbl 1.1f [‘$’ for help]
JL3_GRBL_v1.0

$$ output:

$0=6
$1=255
$2=0
$3=3
$4=1
$5=1
$6=0
$10=1
$11=0.010
$12=0.002
$13=0
$20=0
$21=0
$22=1
$23=3
$24=400.000
$25=3000.000
$26=250
$27=10.000
$30=1000
$31=0
$32=1
$100=80.000
$101=80.000
$102=80.000
$110=9000.000
$111=9000.000
$112=9000.000
$120=1000.000
$121=1000.000
$122=1000.000
$130=220.000
$131=280.000
$132=1.000

there was an early issue with not being able to home, so I sent $22=1 and the lightburn home button works now.

$# output:

[G54:0.000,0.000,0.000]
[G55:0.000,0.000,0.000]
[G56:0.000,0.000,0.000]
[G57:0.000,0.000,0.000]
[G58:0.000,0.000,0.000]
[G59:0.000,0.000,0.000]
[G28:0.000,0.000,0.000]
[G30:0.000,0.000,0.000]
[G92:0.000,-360.000,0.000]
[TLO:0.000]
[PRB:0.000,0.000,0.000:0]

The Issue

In the $# reply, G92 reported 0, -360, 0 <<<------ how do we fix the -360 and where did that come from?
If this is put in the console after the homing “event” occurs:
G90 X0 Y0 Z0

then $# reports everything as 0

Somehow the home operation is doing something more than just finding zero. Anyone know how to fix that. I tried to look in the obvious places and I’m not sure what to look at from here. Any help is appreciated.

[dkj4linux]

I’m afraid I can’t address “fixing” your issues but can point you to the fairly lengthy “$79 laser engraver on Amazon… any good?” thread – that you participated in – and might help you remember some details about this little machine.

$79 laser engraver on Amazon... any good?

This machine is designed to home to front-right… that’s where the limit switches are located. Personally I don’t use homing… I prefer to use a “user/job” origin for each job. In your Device settings, you can turn off auto-homing if desired. I think @cmenard’s Grbl settings are supposed to handle homing and limits properly… and @RockinRiley has confirmed. Until you get the Grbl settings straightened out, however, the machine will often get “lost” (think it’s out of bounds) and lock up (refuse t…

IIRC the Grbl firmware we loaded onto that machine was actually for a similar but different JL3 machine… that I think was a larger version using the same controller. Maybe that’s where the Y -360 coordinate can from?

As I shared in the post above, the JL1 machine runs quite nicely IMO in “current position” or “user/job” coordinates… without the need to “home” it. I find the machine is so small and it’s easy enough to simply manually place the laser where you want the job origin to be and then power it up. I’ve still got this little machine and found it really handy for small jobs like ceramic and/or slate tiles…

– David

[orob]

Thanks for taking time to respond. I remember the conversation because that was why I bought the laser, however, I missed that subtle detail of the JL1 vs JL3 size and so that makes a lot of sense for the offset. There has to be a way to change that offset. I’ll keep looking, but that won’t stop me from using the laser.

I’m trying to laser some leather keychain fobs and they are all small and alignment is everything to get the image on the fob. In my mind, it makes sense to home and then offset some known amount to be able to consistently mark them, but in that thread, I see you simply placed a square for the tiles to get a repeatable position or used a laser marked square for the location.

Do you recall the focal length of your JL1 laser?

[dkj4linux]

With all my laser modules with screw-in lenses, I usually just preset the module to focus at 50mm (or some convenient value) and then cut/printed a gauge block (material surface to bottom of module housing) to allow quickly setting the focus for a job. That, of course, requires an adjustable Z-axis mechanism(s)… several of which I developed later in the thread.

When I set up for a “run” of ceramic tiles, I always used “center origin” and a tile with diagonal markings to lightly fire the laser at… to locate where the laser should start for a job. I also set the finish position to return to the start position and be ready to do the next tile. If you never manually move the module and/or jig relative to one another, you can power down and back on again and still be properly located for the same job type. If you need to move the laser away to load in new material, simply jog – using the arrow buttons – to move out of the way by some set amount and then jog back by
that same amount to be in position for the next tile.

[RockinRiley (Riley)]

I justused mine 2 days ago. I am not able to get out there now, but my settings are the same as above. Copied right from our forums. It seems like you have to home to lower right on lightburn. I am very surprised your friend could use lasergrbl. It was very upset with the homing and you had to flip your drawing, so j immediately bought lightburn. If you cannot get it, let me know. I may have time to get to the shop and see. 2 things come to mind a) the size may not be correct in grbl b) the homing corner is wrong

[orob]

I think for lasergrbl to work I had to reverse the axis with $3=2 or something like that and then it worked, but that was over a year ago and I was thinking that extra home grinding was from something I did from that, but maybe not. The hope was that in exposing all the data, it would be very easy to find, but that doesn’t seem to be the case. In the end I think David’s comments above should allow it to work as long as I put it back in the same home spot between uses. ($22=0 means no homing). I’m out of time to solve

[RockinRiley (Riley)]

Compare to these

$79 laser engraver on Amazon... any good?

I picked one of these up as well. Thanks for posting the GRBL update. Here’s the settings I ended up on to get all the soft limits and homing working properly. GRBL 1.1f Settings $0=6 $1=255 $2=0 $3=3 $4=1 $5=1 $6=0 $10=1 $11=0.010 $12=0.002 $13=0 $20=1 $21=0 $22=1 $23=3 $24=600.000 $25=3000.000 $26=250 $27=1.000 $30=1000 $31=0 $32=1 $100=80.000 $101=80.000 $102=80.000 $110=9000.000 $111=9000.000 $112=9000.000 $120=1000.000 $121=1000.000 $122=1000.000 $130=220.000 $131=280.000 $132=1.000

[orob]

It works with $3=2 or the x axis goes backwards. If i home it manually front left then it runs the same every time if i use absolute coordinates.

I turned off auto home in lightburn and set $22=0

(Thought the kerf would be wider, so i had double outline, but wont do that anymore)
Seems to be fine.

[RockinRiley (Riley)]

Well i have one more christmas item to do. Hopefully i can get you my settings very soon. It is michigan and freezing right now. Shop is in the garage.

[orob]

I’m in minnesota. No worries on it. I’ll ask again next year. Once i finish this run of fobs, it may or may not get incorporated into the lr4 or just mothball… Tis the season.

[RockinRiley (Riley)]

Merry christmas!

[dkj4linux]

Merry Christmas to y’all, too!