I’m getting some odd behavior. I’m running a K40 with a smoothie board. It does the job fine, but then I get alarm lock errors in the console:
Starting stream
Layer C01
Layer C01
error:Alarm lock
On or near line 0:
error:Alarm lock
On or near line 0:
error:Alarm lock
On or near line 0:
Job halted
Stream completed in 0:00
error:Alarm lock
error:Alarm lock
error:Alarm lock
error:Alarm lock
error:Alarm lock
error:Alarm lock
error:Alarm lock
error:Alarm lock
error:Alarm lock
error:Alarm lock
error:Alarm lock
error:Alarm lock
error:Alarm lock
[Caution: Unlocked]
ok
ok
Caution unlocked is when I hit the Home button, and then I can continue working.
Ah, I see it now. The config has alpha and beta maxed at 300x200, but I have LB at 320x220. The actual bed size is 330x358, but obviously the laser can’t reach the border areas (though there is no vent duct in the way).
Is there a simple process to determine the actual max laserable area?
You could try start at the extremes of 300x200 and then literally just increment a mm at a time to see when you hit the limit, then back off a little to provide some insurance. Do that for each axis.
You mean from the Move box in LB? How would I start at the extreme in that case? Pressing Home doesn’t bring me to the true 0x0, it can travel about an additional inch on x/y.
You wouldn’t necessarily need to be at the extremes. Just looking to save time. But for X-axis… just see how far beyond 300 you can get. And same for Y beyond 200. Record those values and set for config.txt and LB Device Settings.
See if you can get negative numbers in this case going away from home to get total dimensions. Or if that doesn’t work, set the bed size well larger than actual and work backward until you bottom out. Take the difference to get you the usable size.
With the bed size set in LB and the config at 320x220, Home isn’t in the extreme corner. From Home, I can move Y up 19mm, and X over 9mm before either alarm hits.
So do I set to 319 x 209, or what? This setup is odd…and doesn’t represent the full workable area. Does that mean some coordinate is set wrong?
I don’t know the actual answer to that question. Before swapping out the m2 nano board, Home was top left. So that’s how I set it with the new board in LB. When I open other people’s files, I have to flip them horizontally. If I set the origin in a way that does not require me to flip the image, then it burns reverse.
Using my own files, origin/home set to back left, I can import and burn and everything looks as expected.
I’ve had a strange drop in performance, so I think I might need to clean my laser lens maybe after 1 day of slightly heavier use…either that or I somehow screwed up the laser alignment when I took out the stock bed to measure it.
Home and machine origin are not necessarily the same thing. Not sure about Smoothieboard but for C3D they actually call this out: Device Setup in LightBurn - Cohesion3D
However, if you’re saying that a different origin results in a mirrored burn then might be fine.
So I think I’m oriented now. So you’re saying home is 0,0.
In that case then yes, I think you could probably set 319x209 as work size.
But… what do you mean by it not representing the full workable area? I had previously thought you were hitting a limit switch when this error came up. That’s almost certainly true for the Hard limit -Y error. But if the other errors are soft-limits then you may be able to temporarily extend the bed size in config,txt to see if you can eke out even more space.
Well, it’s odd. Those limits happen near the home position because that’s where the only hardware limits are, and that’s where I’ve been putting the material to engrave.
If I measure opposite corner from that, I believe there is more travel than those dimensions. The duct that I removed took nearly 2 inches of real estate from the back/home side of the bed. Now that it’s gone, I would think that space should be available. I guess I need to start from home and move outward/positive until it stops.
That’s what I’m saying- the Y limit switch is nearly 2 inches BEHIND where the vent used to be. If I left it in, I could have engraved it.
When I click Home in LB, it’s 19 (Y) and 9mm (X) away from the limit switches in the back left corner (without engaging the switches). 309mm from Home to the X far right physical limit. 216mm from Home to the front rail without getting tooooooo close to the rail.
Got you. I thought the vent had been impeding travel.
I must not understand how your homing works. Normally the homing switches are engaged in order to determine home. Not sure why you’d be so far away from the switches.
I’m not super familiar with Smoothieware. Does homing hit the switches quickly, back-off, come back toward the switches more slowly, hit, and then back-off a small amount? If so, its it backing off by the 9 and 19 mm for X and Y respectively?
Not the way it is now. It would be the 309,216 mm. We’d need to sort out how to reclaim those extra 9,19 mm.
Do you have something that looks like this in your config.txt?
alpha_homing_retract_mm 5 # distance in mm
beta_homing_retract_mm 5 # "
gamma_homing_retract_mm 5 # "
If so, what are the values? Hopefully 9, and 19 for alpha and beta. Haha.
I think I figured out the stupid issue. And it was stupid. Device Settings had “Return to Finish Position” set at 0,0, which is what I believe was actually causing the errors. I changed it to 5,5 and ran a couple jobs without the error.
It’s customary to return to 0,0. I’m curious why it would be triggering the switches especially if they’re 10,20 away from the switches… What is the position of the laser immediately after homing? I’m guessing that it’s 10,20 or something greater than 0,0 at least.
You could probably recover a few more of those millimeters. Just pick a comfortable pull-off value and then add those to the overall bed dimensions.
It’s exactly 10,20 from the point of triggering the stops. I changed the retracts to 5mm. I’ll see if that makes any difference.
I did a quick test. I moved the laser head to the 4 corners at the most extreme points it’s still usable, and I got 325x235mm measuring between the laser marks. I’ll see how that goes now that the settings are updated.
If I’m setting the Home retracts to 5,5, should I be subtracting that from the 325x235? If yes, why? The laser has no problem going back to the starting point beyond home if laid out that way in LB.
I guess Home and Origin being at the same corner is slightly confusing, but changing origin to a different corner makes it weird.
If I’m keeping up with all this then I think the answer is no. In fact, I think you should be adding 5,5 to each of those so that it’s 330x240. The way I’m thinking of it is if the new post position is 5,5 and you can get a full 325x235mm from that point that means your true bed size is 330x240. Otherwise you wouldn’t be able to address the area beyond 325x235mm.
I guess this means that you’d have to avoid using the areas less than 5,5 mm though. I’m wondering if there’s a way you could offset the origin position to account for that.
It’s fairly conventional for a lot of diode lasers. Just different than “standard” K40 but not any worse. It may be possible to move the origin position. Don’t know if this would require a custom build for Smoothieware to do so.