XY home position

I guess I didn’t read into it that placing a max cut dimension rectangle around the exterior of every cut file, then placing what you wanted cut a known distance inside from these edges, would then result in a guarantee that when the SVG placed into the UI (without moving it) would auto locate the SVG’s “actual cut” correctly in a consistent location that would allow for a fixed 0,0 to be placed inside the the Glowforge’s cut area and consistent placement of the item to be cut resulting in the accuracy required.

Engineer, not an English major. Run-on sentences abound.

Exactly…

…and exactly. :slight_smile:

No, tony was just referring to it that way to follow the conversation. The “upper left corner” actually changes with the head speed, as when you’re doing high-speed engraving the physical limits are different than when you’re doing slow cuts.

This is a key point: what is being discussed as “0,0” - that is, the northwest most addressible corner - will change with the speed you use.

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One more very important note: Tony’s request was not for hypothetical machining operations that illustrate your request, but actual use cases that you, personally, are thinking about doing that motivate your request, with the more detail the better. We don’t build features because we want a marketing checklist, but because of real-world problems that you help us understand are common and important to you (like the lightswitch example).

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OK, the camera doesn’t move. Fine.

Does the lid use some magical zero play hinges? They would have to be something special to have no play after lots of use.

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The lid snaps into place and is registered on all sides so it sits repeatably.

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Suppose I want to cut a large acrylic door for a 3D printer with holes for the hinges, door knob and a large engraved name, perhaps a decorative engraved border, perhaps a trench for a sealing strip.

For all but the first and last cut the corners won’t be visible. It will just be two edges and what it has cut already. Perhaps it can engrave fiducials in the waste margins as it goes.

Lots of examples where I have a part not was not created in a laser cutter that I need to add a secondary operation to the part. Creating text on a small ridge or detail inside a small dia circle. Being able to precisely place a part on the bed and perform that operation is highly beneficial in my mind. Again… artists may not care about precision greater than what the camera provides. People placing fine detail in specific locations on parts or designs do care.

Obviously you picked up on the fact that I robbed the picture above from work where the part is a large bore drive stub shaft. I would never obviously use that part in the glowforge. My point in using it is that the picture is irregular in shape with text registered vertically on a thin ridge. Text that is off center would ruin the part. Precisely placing the irregular part in the bed using a guide on the bed and placing the svg text drawing in a precise location in the UI makes this job easy.

.#2 on that list - Argh, it wasn’t a template for cutting out snowflakes, it was a test for them to see if they could accurately produce repeatable cuts.

It’s something I don’t think they’ll be able to do until down the road when edge detection is in place. It’s no easy feat, but if they are able to do it without a jig it might mean their software is accurate enough for me to not need to use a physical alignment tool

This is pretty much the need. Another example could be drawing a perfectly even outline around the apple logo on a laptop/phone.

For me, engraving text or accent lines which are perfectly centered on the ridge of a casted item just pulled from a mold is a need.

Another example I’ve run into is when using 123D make, sometimes the software glitches and doesn’t include the alignment rod holes in the template for the piece you cut. Happens all the time. I know exactly where they need to go in distance from 0,0, so I just put them in one at a time.

However if they are off just a little bit it will screw up the entire alignment of the pieces and I’ll have to do a bunch of rework which could take a while. I learned this the hard way when I didn’t type in the distance to the right number of decimal places and I had a ridge where the two connected. Big letdown.

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Is there a reason @tony or @jamesdhatch that “your” y-axis zero at the north edge? Seems un-intuitive. Does the interface for your machine have you put negative values for Y?

In junior high math the 0,0 point was always lower left… and CAD software follows that approach, though the 0,0 can be moved to any point and values can be negative. (i.e. if my 0,0 is at the top left of the screen, then anything in the middle of the screen will have a positive X value and a negative Y value. Of course, in CAD you can also rotate the display… but it’s pretty bad-practice to do so.

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north edge is because thats generally where lasers home to. its where all the mirrors are closest together and the gantry isnt in the way of the bed

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A simple way to determine home position. Draw a heart on a blank piece of Proofgrade material. The overhead camera captures the image. Home is where the heart is.

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:slight_smile: I really like that. Maybe add some shoes “there’s no place like home”

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Needs to be cut from red sparkle acrylic.

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@dan a very simple and straight forward use case that I think many people will encounter is a little thing I call “the screw up”. If we are not using proofgrade (hey it might happen) and our lines do not cut through the first time, being able to register would save us.

If I get in the habit of placing material up against a set of stops (I am OK making these stops) then if something happens I know I can get the piece back in there and register it to try again. If I pull it out and find a mistake and have to reposition by eye, I have doubts about my chances for success.

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HAHAHA yes. You know… this didnt even come to mind, but it is probably the most common reason on my k40. Especially when cutting through ply.

“Ah… smoke is coming out the bottom, its good to go. Oh crap… no its not, back in the bed”

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Again I think a revolutionary machine with two cameras should be able to just index off a corner and repeat the cut with the work placed anywhere on the bed and only roughly oriented. No harder than pass through, although that looks quite a lot of work to me. Shame it wasn’t already done when first advertised.

  1. Optical Alignment

The dual cameras align the laser head with the frame, with your design, and with your material. Glowforge realigns with every cut and engrave, adjusting timing and position, so every print comes out perfectly.

Note this is superpower 8 but discourse has rendered it as 1.

I have noticed that discourse does allow an out-of-order list number.

Geez. Is Discourse a Microsoft product?! :slight_smile: - Rich