Research: Sizing question

I’m just about ready to start building and I’ve been doing a bunch of research on what size to go with.

I know the recommended size of the 24x24 (exterior) but my plan with this is to only cut wood and I wont care if the tolerances are off as long as it isn’t noticeable. .

I just built a table to hold the CNC and I was planning on having a usable work-space of 24x24 (Interior) with a 35x35"ish size for the exterior. Do you think I’ll have any problems? I heard about the EMT warping but I wasnt sure if I would be experiencing any of that at this scale.

Heres the table I built for it

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36x36" is probably the largest emt build without mid-span supports. An online calculator set the conduit flex at approximately 0.2mm which is fine for wood, as far as I’m concerned. Mid span supports would reduce that to slightly over half.

Okay sweet! Do you think I should just plan for the mid-span supports? I’m still a ways out from finishing the build but I’m trying to figure it all out before I start committing to a size.

Might as well. There’s one that’s designed to use the same size Z legs so you just get twice as many.

My build was a 24 x 24 usable space. I build a 4ft by 4ft table/enclosure. Here is a pic from when I was completing.

I use it for the same purpose as you intend. I have no supports and works okay for me. Here is my project log:

Wow! I’m very impressed!

I’ve basically dug through the forums looking for confirmation on the size and I’m glad its able to work so well for you!

Do you think the enclosure is necessary? I was going to test a few different dust shoes and try to get there without having to seal it up tight.

Let me ask you this first. You plan on operating indoors? By that I mean inside a house/basement, or instead in a shop/garage. Then I can give you a better (much longer) answer.

P.S. I started from scratch on all of this in terms of knowledge. Someone literally told me to goggle “MPCNC” for something to do :slight_smile:

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I set up a corner in the garage for it so I’m not really concerned about the noise mostly the cleanup.

I heard about the MPCNC on YouTube but wasn’t fully aware of how affordable it was until last week and now I’m fully committed!

So here is the best answer I can give. Then I will elaborate.

When all is said and done, I would design my table and work area so you can easily add an enclosure later. Basically that is what I did. Now let me share my experience on noise and dust collection / cleanup.

Disclaimer: Always wear eye/face and hearing protection when using this thing even if it enclosed. That’s what I do.


Short version, it only kinda helps reducing noise. Most importantly, if you use some form of dust collection, the shop vac will probably be outside of the enclosure. So you kinda cannot win on this one.

Dust Collection

Short version is I personally think it really helps. Here is why. When I started testing my MPCNC I did some simple engraving in pine with a 1/8" up-cut bit and dust collection on. In general, that was not messy. I thought, this is great. I don’t need an enclosure.

However, I built one anyway. I was glad I did.

When I started trying other bits and material, it did get messy. Here are two examples:

  • MDF: I actually don’t like cutting this. It creates a fine dust (which is probably 50% glue).
  • 1/4" Up-Cut Bit: So I love this bit. But because it is physically longer, the spindle rides higher (farther away from the material). As such the dust collector works good, but not great. It also can create bigger chips that go farther. The enclosure really helps here.

My point is that you might be able to get away without an enclosure but you may change your mind.


Thanks for the response! These are really helpful!

I’ve heard about hearing protection but I wasn’t sure how important it was. I’ll definitely look into getting some!

But since I don’t really care about noise too much I was thinking of surrounding it in a thin layer of something similar to those plastic picnic table cloths just so the dust doesn’t fly everywhere and I can dismantle it pretty easily.

My build was a 24 x 24 usable space. I build a 4ft by 4ft table/enclosure. Here is a pic from when I was completing.

What was your usable Z-height for your build? The picture looks like you have it pretty low.

I use 4" Z corners, which gives me 2" from the bottom of a 1" cutting edge bit fully seated to the top of a 1/2" spoilboard, if that helps.

Is the 4" Z corner the length of tubing you cut for each corner?

Sorry for all the questions, I’ve heard you want to keep that as low as possible to increase rigidity

Yes, that’s correct. 4" is the conduit length.

Okay perfect!

The hardware and electronics just came in today so all i have left to do is finish the 100hrs of printing!

Do you still need me to check? Mine was indeed pretty low.

I’m sure 4" is more than enough.

I read that a lot of people aim for a 12x12x8" work space and I was thinking at this bigger size 4" would work.

Did you go with the Dewalt 660 for the router?

I’m using a Makita 0701, similar to the dewalt 611. I wanted the built-in speed control with rpm monitoring so I didn’t have to mess around with it too much. I looked at spindles and auto speed control but it gets very complicated and expensive quickly.

Yup, the 660. I did not go and measure the size, but I think I used the default Z height in the cut calculator. Which is usable size of 3" (I think a 2.5" cut for the tubing).

What’s the thickest material you’ve worked with?

I can’t imagine I’d ever work with anything larger than 1" but I also haven’t ever worked with a CNC machine before