I’ve searched these forums and haven’t see a definitive answer, or if it is even possible, on how to set and maintain an accurate home position on the D1 Pro using Lightburn.
Here’s my process:
Push the laser head to the top left manually
Turn on the D1 Pro and press HOME
Run the Power (Fire) to have it make a mark where the laser it positioned.
Press the HOME button again
Run the Power (Fire) again and have it re-mark the laser position.
When I press home, the laser moves to the top left corner and is stopped by limit switches. HOWEVER, the laser head does not come to a graceful and accurate stop. Rather, it hits the X and Y limits and then appears to “bounce” slightly off those limits. It is HERE that it appears to have some play in where the head starts a new job. If you are trying to tile a project, or even cut multiple layers one after the other, there is zero accuracy and predictability.
So my question is…is this normal? Is everyone dealing with this? Or is there a workaround that will deliver predictable results? IE, a way to make my D1 Pro go to the EXACT same location every time I want to start a new job?
Is setting the origin the answer? Go to origin before every job, as opposed to pressing HOME?
Any advice would be greatly appreciated. I feel like I’m taking crazy pills…
This shouldn’t be necessary. The homing process itself should account for this.
If I’m reading this correctly the general cycle is correct. Homing is a 2-step process. The first step is to make initial contact, then the machine should back off and then reactuate the switch at a slower speed, then have a final pull-off. This is meant to increase accuracy. It should do the second step of this for both X and Y concurrently.
How much variance are you seeing in the final resting position? Very precise machines will get you spot-on, many will get you within 10ths of a millimeter. Poorly tuned machines will get you within a a couple of millimeters.
Sensor type and external forces can affect how repeatable the homing process can be. I’m not familiar with how precisely a well tuned D1 Pro should be able to home.
However, where people have had noticeable issues it’s generally been due to physical mechanical issues preventing proper homing. Check that cables or other equipment are not hindering the homing process. The machine should be able to move freely through the full range of the bed. There should be no additional strain as the laser head approaches home location. If there is, try to eliminate anything that would impede travel.
This could work if you were to have a repeatable way to set the origin to a known physical location on your bed. You would then be required to use “User origin” exclusively.
The gantry looks like it’s possibly mounted upside down. I’ve never seen the cabling channeled on top of the gantry. I believe it’s meant to be channeled below the gantry.
I suggest you review the assembly guide to make sure nothing was missed.
It only looks backwards because I re-routed the wiring per this video on Youtube. I was having issues with the wiring getting bound up on the right side of the bed.
I altered my setup a little from his, though, by electing not to route the cabling across the back of the gantry. I mounted square zip tie holders and ran my cables across the top. I also used one of the mounts to keep my air assist tubing from getting too unruly when hitting the outer extremes of the laser bed.
As it stands, I can manually push the gantry all the way back to the back rail without it hitting any of the wiring or cables. It still, however, will not stay against the rail. When you push it all the way back, it bounces back forward off the rail.
This is part of the HOME issue, I believe, as it accounts for the laser head not stopping exactly on the X-axis when homing. Of course, that might be due to the limit switches, but the result is that sometime it bounces back 2mm and sometimes it bounces back 4mm.
What I need is a solution to help remove that variance on the laser head when I click HOME. Hope this is making sense.
I suspect that’s exactly the issue. Can you see what it is that’s providing the spring force back? Is it something that pressing being pressed against?
The other possibility is that the left and right sides of the gantry are not square to the frame. Could it be that one side hits the back earlier than the other? If so, you would need to resquare the gantry.
Are you saying beyond removing the physical mechanical component causing the spring back?
Alternatively you could relocate the stop tab so that it’s farther away from the back. That would avoid the spring back issue you’re seeing.
As I mentioned earlier, from the Youtube video I chose to re-route the cables on the top of the gantry. But at some point the cable has to come down the back of the gantry to be plugged in. Again, going back to the setup video, it gets a little fuzzy when explaining where and how that cable comes down.
In this picture, it appears to be in front of the gantry:
So my main issue is that black cable. I believe that is what is causing my bounce back at homing. If I can determine where that is supposed to come down on the gantry that might provide the solution.
I’m not obsessing about this, but I suspect cable management might be an issue for others and there are a number of things going on here that might be problematic. Hope I figure it out, but also hope it helps someone else going forward.
I’ve had zero issues with repeatability. While using the little stick on zip tie holders would be better, I didn’t have any, nor did I feel like ordering any, so I just used the existing holes.
I like how you have routed the cables outside away from the bed. Unfortunately, I have the xTool enclosure, so I don’t have the room to route in that direction. It makes sense, though, as that group of cables protruding out the back of gantry can also cause it to bounce against the back rail.
Still fighting this issue. I’m thinking about routing my cable like yours, but I’d have to move my laser out of my office without the enclosure. Have you tried your solution with the enclosure on yet? I’m curious.
I apologize, but I have not tried it yet. Maybe try moving the side out a little, since it’s a velcro flap, there should be tolerance to let it come out without compromising the enclosure.
