Alignment off more than ever expected

makes perfect sense… but “coaster” was a “easy to explain” setup…
but it was more of something to “etch on” like a slate tile. i didnt want to get too specific, because i didnt want to get into a new topic on non-pro-grade materials…
i just want to hit a targeted area.

thanks… screencap time/date are in the file name i believe… and im in saint louis, mo (CST.)

that makes perfect sense. and a definite work-around… sacrificing a piece of cardboard to see where it lines up then setting the “good” material in it’s “center”

thanks… lid WAS totally closed… and proofgrade material with correct thickness was in the bed.
the only thing i notice in the screencaptures are that the code on the material and the image is a bit “blurry” - maybe the lid camera needs a screenwipe?

If you click the link, the explanation was for setting up an engrave with irregularly shaped slate coasters. I just threw down the quick and dirty, its much more detailed.

I also did a similar technique with a (full bed-sized) cheese board using a single edge to align it. Jigging is a really useful skill in GF-world. You can see my alignment material on the left in the second picture.

I have to set a weight on the right side lid of my glow forge when I close it to get a more accurate location. Looks closed but adding 5-10 lbs to the right side makes mine go from being off over 1 inch to being within 1/4 inch.

I always use a jig when trying to engrave anything that needs precision. Works very well.

1 Like

Thanks! - will try that tonight… was yours off to the right or the left?
(trying to figure out which side to place the weight on)
also wonder if there’s a fingerprint on the lens? (i havent touched anything since setup) but DID notice after 3 small jobs - lots of streaks in the glass showing up (im sure the soot/smoke makes things like oil and fingerprints stand out quite well)
would something like that really cause alignment, though?

i thought the laser had its own focus-able head that determined “depth” but not left-to-right alignment…

and STILL… having to weight the lid… and being 3/4 - 1" off… doesnt sound right.

but thanks! will try and let you all know

The laser does have its own camera which is used to focus the laser but it has absolutely nothing to do with the placement of the design on the material, nor is it used to measure the thickness of the material to determine placement. Because the lid camera lens is a fisheye it is greatly distorted. The software needs to know the accurate thickness of the material - a little bit makes a major difference. You can experiment and change your settings to manual and set a manual thickness and see where it says it will cut. Then change that thickness very slightly and see how much it will move where it thinks it will cut. Its amazing how much it will move it with a very little change in thickness. Since the camera is on the lid any change in height (by the lid not closing to the same position) will also effect where it thinks the cutting will be.
I just happened to stumble on my lid thing by accident. I was multi-tasking. Setting up a job to engrave on the glowforge and setting up a job to cut on my cnc router. I had a box of clamps that I got out to hold the piece on the router that I set down on the glowforge. I left it there when I set up the engraving job and found that the engraved location was a lot closer to where it said it was supposed to be than normal. Without the box it would cut further to the left than it would show it would.

that’s perfect… thanks!
makes sense… i was probably just too impatient, expecting it to work like a 3D printer

Make sure your crumb tray is seated in the little divits underneath, and that there is no debris underneath it.

As I’ve struggled with things aligning, I’ve made “jigs” with paper at 1000/12, but just for one off pieces. If i make a jig of cardboard or plywood, and I want to take it out, do something else and put it back in, will the registration be maintained? I guess I would first have to use my paper test score, and the coasters would have to be in a group that doesn’t falter from the original positioning to each other.

Hmm, I didn’t think of this “fix.” I had to remove the pass through guard from the front to get the door to seat fully, because it was being help up a little by the crumb tray. It improved after I did that.

5-10 lbs of what?

No guarantee because each time the machine homes it lines the head up with the lid camera, not the crumb tray or the case. If the lid closes consistently in the same place and the neural net looking at the camera is consistent and you manage to line your jig up with the casing then you might get lucky.

I put a small box on the lid to weigh down the right side. Box weighs 5-10 lbs depending on how much stuff I have in the box at the time. It has helped my alignment - shouldn’t have to do this but I do and its easy enough to do.

1 Like

Shrug. My jigs line up over and over and over regardless of machine on/off cycles, cutting 4 or 5 different ones and then putting them back in to run the jobs, etc. The only caveat to that would be removing the crumbtray and putting it back in.

In practice. Not theory.

1 Like

thanks… double checked… and it was (and still is) definitely in there without anything below -but good to look for in the future - appreciate it

Thanks for all the helpful troubleshooting questions.

@chris.mouser, can you confirm that your wire ribbon is arranged in the laser arm like it is in this photo?

image

If not, remove the printer head and gently rearrange the wire ribbon so that it matches the photo. Then reattach the printer head.

After your wire ribbon arrangement matches the photo, print the Gift of Good Measure on the piece of Draftboard we provided in your starter materials for troubleshooting. Be sure to place the print on the left edge of the bed.

Let us know how it goes!

For those who have trouble with the lid closing properly, try lifting up the front corner(s) of the machine and see if that affects the lid position. I found that the first desk I used for my Glowforge was not flat or sturdy enough, because it made a significant difference in the lid position to shim up the front right corner of the machine. On its current table, it doesn’t have this problem. It’s fairly sensitive as the case easily flexes.

3 Likes

I second what @chris1 said. I was using a weight on the left edge of the pre-release until I moved the machine to another surface so I could get to the fan grill in back. Sitting on the other surface I noticed that the lid had a rub where there hadn’t been one before.
When I moved the machine back to its home not only was the rub gone, but the lid shut completely. Looking at before and after pictures of the placement, it had been repositioned about 2 inches from where it had been.

The lesson is that few of the surfaces we put our lasers on is dead flat like the stone slab they calibrate it on at the factory, and the lid fit can be affected by the flatness of the surface the glowforge sits on.
Shimming under the machine can correct it, the only problem is figuring out where to place it/them.