Cut depth doesn't match settings

New Shapeoko 3 XXL user here… Trying to create a threaded waste board with a file from Myers Woodshop and even though the max depth is set to 0.08 (which is confirmed in the g code), my cuts are coming out at about .158.

I’ve checked the tension of the Z belt, I’ve reset zero at the top of my stock 4 different times… What am I missing or doing wrong? I can’t find any help in a search.


Hi welcome, Mitch!

How thick is your stock? When you’re zero’ing are you using the paper method, BitZero, or some other strategy? Your cuts are off by a consistent .150” each time?

Thanks for having me.

My stock is 3/4" MDF. I’m using the paper method to zero. At first my cuts were even deeper, at .22ish, but I’m pretty sure that was a zeroing error because I jogged the Z lower than it needed to be and didn’t catch that I was lowering by .1.

Figured this out on my own. I have the Z plus, which means I have to double up my wasteboard -_-

The MDF being sandiched between the base plate and the top piece was raised in the back, not being fully held flat against the base. This caused cuts towards the rear of the board to be much deeper while cuts at the front were either perfect or too shallow.


With the Z-Plus, you need to double up your wasteboard? This isn’t something I realized. Why is that?

Thanks for the reference…but I use a 3/4" wasteboard with my stock Z…the comment that caught my eye was DOUBLING the wasteboard. Does this mean that the Z-Plus will not reach 3/4" over the stock baseboard with a bit of say 1"?

I believe that those with a Z-Plus have settled on 1-1/4" (3/4" + 1/2") of wasteboard to allow all tools to reach.

OK thanks. Just another consideration in the decision of if/what to upgrade.

I wish it posted the whole post as is, but if you expand the quote from Edward that I posted, he included a DIY easy tram plate that would bring you back to belt driven Z depth if you preferred that route. There are options.

1 Like

Yeah, as someone with only 3 operations under my belt I’d rather just double up the wasteboard because it’s easier than messing around with machining aluminum for now. I think at some point I will jump in and do that, but this is a good temporary solution. I don’t need that extra depth on cuts or anything, so as long as both boards are flat I figure I’m okay (especially after a surfacing pass).

I just got mine put together and had one side barely touch the original wasteboard through the 3/4" I was drilling to place on top, when it did the other side it went over an inch down. I can get another one to double up but that doesn’t seem like it would fix the problem of one side being so much different. Everything is level on the machine, haven’t checked the spindle level yet but that wouldn’t cause this either. Any thoughts? I have the XL and used a file from Carbide but i could not get it to be the size I needed so i just did the same file twice. I zero’d the same both times just on different parts of the board.

Hello Dawn,

Welcome to the community! So you’ve just put together your S03 XL…
A couple of things to clarify:

  • Do you have the Z-Plus z-axis?
  • It sounds like you’re in the process of milling a supplementary wasteboard, correct?
  • Are you just using one bit?
  • Which cut occurred first, the one that went 3/4" or the one that went an inch down (sounds like it went into the baseboard 1/4"?)?
  • Could you share the file from Carbide that you’re referencing?
  • Pictures of your setup/current situation would help.

It sounds like potential belt slip/missed steps, but if you have the Z-Plus or other non-belted Z then that wouldn’t be it; and I don’t believe the Z-Plus can reach the baseboard with the #201 end mill. Anyways if you could confirm/provide more information, we can cross things off.


Hi Brian,
I do have the z-plus. i haven’t actually milled the wasteboard yet, i just drilled the holes and will mill it tomorrow when i’m off work. I have the bit at home so can’t tell you what it is right now but will when i’m at home, tonight or tomorrow.

This is where I got the file I used. And it barely touched the original waste board on the left side but when i ran the same file for the right side it went through the new one and pretty deep into the original. I have pictures of both sides if you want to see them, but not my setup. I imagine it was an error on my part when running the second time but I’m pretty sure I ran them exactly the same way.

hmm… brought up something other than what i was trying to post on where i got the file. let’s try this again.

The Z-Plus doesn’t go down as far so you need to add some height to your waste board. Mine would reach the stock waste board and I had to add three sheets of 1/2 in. MDF.

1 Like

This topic was automatically closed 30 days after the last reply. New replies are no longer allowed.