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Calibration for the vertical axis

Hi guys, I have been trying to setup Maslow and ran into the following issue: cuts on the vertical (Y) axis are off by 1/8 inch. More specifically, I have been trying to cut a square with size of 1.5 inches and I am getting a 1.375 inch side on the vertical (Y) axis.

I had the same problem with the horizontal (X) axis. However, I blindly adjusted the “distance between motors” value until I got needed horizontal side length.

Do you know what parameters I need to adjust to scale the vertical axis? It looks like changing the “motor offset Y” does not help with scaling the vertical axis. Am I wrong?

Any help will be greatly appreciated!

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it’s not a matter of changing one item to scale the Y and a different item to
scale the X, when you changed the distance between motors, you changed both the
X and Y location

see List of sources of error for a detailed
discussion of the problem

basically you need to carefully do the calibration (try a more accurate tape
measure possibly) or try the holey calibration method that’s available with
webcontrol (although you may want to wait a day, it seems a bug snuck in,
probably going to be fixed this weekend)

David Lang

I have a similar issue. No matter how I try to calibrate, My Metal Maslow cuts about 10% larger than the design I draw in cad. I thought it was a conversion error by Etsl Cam, so I always scale my designs to .89% before exporting to the Cam Software. This provides good precision, but still not accurate enough to cut box joints or other scaled cuts. I see with M2 you can scale the x and y with expected and actual cut distances. Is there anyway to get this feature with Groundcontrol, or Webcontrol (I recently got around to switching over). I understand the mechanics of the chain sag and distances between the motors, I just need a fix :wink:

My understanding is that the M2 can’t actually do that. They try to, but in practice it doesn’t really work as well as you might hope because it is different in different parts of the board. Right now the WebControl calibration process is the most accurate I believe.

Thank you for the reply. I’m a bit of an island here, so I don’t know what’s normal, and what’s not. Is this a common issue, and I’m thinking that its only me?

Issues with calibration are by far the most common issues. You are not even remotely alone here.

I have to tell ya, If I can’t draw a part 350mm by 350mm in Sketchup, and generate the G-code with Estle-cam, and have it cut to cut accurately, I’ll have to go to a different platform. This whole time I’ve been thinking it was translation error between the Cad and Cam software. My Maslow is eerily consistent, just not accurate to my drawings. Is there a different combination of Cad/Cam that can help?

Yeah, the consistency is really good and when you get the calibration dialed in it can be quite good too, but it does take a bit of fiddling which can be quite frustrating.

This holey calibration from webcontrol was added to makerverse 1.1.2 as precision calibration where the holes are drilled and measured from the edge of the work surface.

@Andy_Boles in estlcam, how far off are you? Are you cutting on the line or on the inside or the outside of it with your correctly sized bit?

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I’ve done the Holey calibration that is standard with web control 3 times consecutively. I’m using a quarter inch bit (inputted as 6.35mm). The cut pieces are uniformly and very nearly 10% over sized. If I scale my drawing in sketchup to .9025 before sending to Estlcam, I get into reasonable tolerances for most things, like cutouts for receptacle boxes or sinks. The accuracy is just not there to get box joints or dados that need to be precisely the with of the sheet stock I’m using. There’s just too much slop.

For parts, I cut to the outside of the line, and holes I cut to the inside. Whether 20mm or 2000mm the calibration error translates to about 10% growth.

The holey calibration looked good and uniform between all the like measurements. No variation over .25mm which is about what I expect holding/reading a tape. I think 688 horizontally and 1200 on diagonals. Verticals were all uniform too, though I can’t recall the exact measurement. The holes weren’t out of square. The Maslow thinks it’s tuned up. The calibration error correction went from 14 to 4 to n/a during the consecutive calibration runs.

So I think it might be the cad or cam. …Or the Maslow, lol. Same problem with ground control as webcontrol.