Offset cutting and consideration after X and Z-Axis stiffening mod and Eccentrinc nut mod


today I had the time to make a test cust after the simply mod to the eccentric nut and X/Z stiffening mod.

You can find them here if you want to check:

Anyway, today I did a test cut of a guitar template, really simply design on MDF (a Telecaster to be more specific) and in some point the cut, after the first pass, is a bit offset (of a 1mm pretty much). But only in some point.

So I checked all the eccentric nut and they where ok. Not loose and not too tight. The wiring was ok. No short or whatever. To be honest I noticed (after the cut) that a screw of the right stepper pulley were missing so I’m going to replace it tomorrow. Belt tension seems ok to me, but I haven’t setted it with a method, just tightened until they appeared ok. All the axis move nice with just a little effort (with hand).

The X-Axis have little to nothing chatter, the Z-Axis the same. Y-Axis could be a little bit more rigid so I’m planning an upgrade in the future.

I also planned to make the stepper calibration (not the pot current, I have made it) when I find a solid method to make it.

But, for the moment, I can’t make a decent cut, even after everything seems correctly assembled. Any thought?



I need to put Loctite ALSO into the pulley screws!?

I tried today to see how much accurate the machine is, just by clamping a rule and move the machine first with short move, later with long move. On short move seem to be precise, but in the long I noticed a ‘offset’ (don’t know how to call) of little less than a millimeter.

I’m just wondering if is possible that the machine is not square…

Ok so I need to do that. I wanted to avoid it if was possibile but seem that I have no choice.

Anyway, do you have some tips on how to check if the machine is square?

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Mmm reading this I put my bid on the machine not square

Ahaha pretty much. I took a week to assemble it, but I’m honest: When I was near the end, I rushed just a little!


Mmm I guess you’re right, I need to think a little about it tomorrow.

Thought I was planning to disassemble the whole machine later this year, but since I can’t make a decent cut since when I had it, I guess is better the check everything again.

EDIT: I wanted to disassemble it just to make a better wiring, nothing more.

Did you have any luck finding the culprit for the offset cut?


honestly I haven’t had the time to make a new setup, maybe today.

What I believe pretty much is that I have mounted the machine on the wasteboard/extrusion and let it ‘flex’.

If you pay attention to the 2 Y rails, when you screw them to the wastboard, they tend to ‘flex/bend’, I guess this is the cause of my offset cut in the upper position of the machine. Or at least I REALLY hope is this becasuse I have the machine by 2 month and never cutted something good. Apart some small things.


Mmm I don’t remember how I have assembled my waste board but for sure I can say “in the bad way” because I was missing some parts (as some screw, some t-slot nut etc), so I really hope that re-doing the waste board assembly will solve my issue

I just unscrewed the 8 screw on the Y plate and to me seem that the machine have ‘found’ its own allignment. Could be possibile? Or is better to re-assemble the waste board anyway?

You’re right, better to check everything and be sure than just to try and see how it go.

I’ll disassemble the waste board tomorrow

Ok, I don’t want to burn myself but seem that a change of bit have solved my problem…

New bit made in ‘widia’, and this is the result. Perfect by a fraction of mm. (for reference a pocket should be 80,66mm and is 80.67/68, I guess really ok)

Sure! I’ll make more test tomorrow, but as is work fine for me. For sure I can make some calibration after some other work I really have to do