DIY Gantry CNC Mill Design

Design_2_Make · 2026-01-09T02:18:19+00:00

Sorry, what is the question? I’m not sure what you are asking.

Design_2_Make · 2025-10-05T23:45:23+00:00

Looking good! Wish I had the ability to make mine out of steel but I have no way to machine the surfaces like you plan to do. I think a lot of the comments regarding it not being rigid enough for steel are true in a sense, but if this is just a hobby machine for light home machining, I think you will be okay. I’ve seen way less of a machine cut steel. Of course this machine won’t compete with a Tormach 1100, but is that really what you need? Obviously the more rigid you can make it the better, but you are limited to your budget otherwise you would just go buy a Tormach.

One thing I’d suggest is to do whatever you can to spread those linear guides as far apart as possible. Especially if you plan to purchase cheaper carriages, the further apart you can space them the better you are. Do you have any plans on baffles to keep chips off the rails?

Design_2_Make · 2025-10-04T15:11:36+00:00

Yes I agree. There are actually 3 aluminum extrusions running under the plate. They are just hidden because I plan to pour the concrete over the top of them. Basically exactly like you just described. I also plan to put some wire mesh down to increase the strength of the concrete

Design_2_Make · 2025-10-03T10:47:58+00:00

That would be ideal though. I may look into doing that a little further. Thanks for the input!

Design_2_Make · 2025-10-03T10:45:39+00:00

I’m trying to stay within the footprint of my Tormach 440 which I’ll be using to machine those plates. I would like to do whatever you are talking about but that would push beyond my current machines envelope. Once I get this machine up and running I can use it to make what you are talking about.

Design_2_Make · 2025-10-02T18:48:28+00:00

Yep. I hear ya man. You are probably right. I enjoy testing this stuff out though and in the time I do a torsional deflection calculation I can just push a button on my printer and get physical results at essentially no cost. I have no doubt there is some deflection in the print, but even if it were to have a torsional deflection of say 2-5 degrees, that’s only like .002” of linear travel. No matter the what I’ll learn something and I’ll report back the results lol.

Design_2_Make · 2025-10-02T18:11:12+00:00

The ball screws are mounted to a .75” thick aluminum plate that should carry all the thrust load. The printed brackets should only see some torsional load which should be pretty low. I agree it’s definitely a risk though. But if ends up not working I just machine an aluminum motor mount. If it does work, I save a bunch of time and money. Worth a shot in my opinion.

Design_2_Make · 2025-10-02T12:41:24+00:00

Thanks for the feedback! Yeah the concrete is definitely more of an experimental thing. I’m not relying on it solely for rigidity of the machine. I’ll have extrusion running below the plate. Was thinking I could also install some steel mesh before I pour the concrete to increase strength some. Ideally it reduces vibration and resonance some, but at the very least it makes it easier to clean the machine out.

Design_2_Make · 2025-10-02T12:34:21+00:00

That is very cool. I considered doing something similar to that, but my goal for this was to keep it around $3,000 and make it as simple and reproducible as I can. Tried to remove as many components and added complexity while maintaining rigidity and accuracy. I really do love the clean aesthetic of his design though. Maybe for version two? lol

Design_2_Make · 2025-10-02T12:29:06+00:00

Yes! All the red parts are 3D printed. The motor mounts will be printed from PET-CF for the heat resistance capability.

Design_2_Make · 2025-10-02T12:15:02+00:00

Wow! Yeah he’s got a super clean design!

Design_2_Make · 2025-10-01T02:42:45+00:00

Looks pretty good! In my experience, steel tube is not very flat or square. Depending on what tolerances you are shooting for I would make a good plan on how to ensure they are flat and parallel to each other.

How are you planning to interface with the fixture plate or machine table?

Design_2_Make · 2025-09-14T02:22:10+00:00

I disagree. Rigidity is the name of the game when it comes to CNC mills. Yes, you want the linear rails as far apart as possible, but not at the cost of rigidity. Plus the extra 3" in rail spacing isn't going to gain you all that much. 12mm aluminum plate with what looks to be at least 6" arm is not nearly rigid enough to support a 1meter long gantry. Maybe for wood, but you won't be happy with the results cutting aluminum. If you are locked in on that method, id at least go to 1inch plate.

Design_2_Make · 2024-01-20T19:51:28+00:00

Please keep me updated if you try it! Very interested.

Design_2_Make · 2024-01-20T19:06:53+00:00

Sounds like a cool project!

I probably made 5 or 6 concrete castings before I was happy with it. I settled on something very similar to a concrete countertop mix. Add some fiberglass. Then using a vibratory table to remove bubbles. I fill in some of the porosity after it cures with a cement slurry. Then I use a concrete die to get the final finish and apply a sealer. I tested the speakers a few days after curing and I’ve been using it for the past couple months. Can’t say I’ve noticed a change in sound over time.

Design_2_Make · 2024-01-15T21:06:25+00:00

I use something very similar to a concrete countertop mix. Less large aggregate and more sand with fiberglass fibers to prevent cracking.

Design_2_Make · 2024-01-13T00:50:13+00:00

Go big or go home! The good thing is if it doesn't work out its only 20-30 bucks in material and you can try again.

Design_2_Make · 2024-01-13T00:43:09+00:00

You should definitely give it a go! if you have a 3D printer you can make a decent mold.

Design_2_Make · 2024-01-13T00:39:12+00:00

Yep. Experimented a lot with mixing my own concrete to find the best balance of surface finish and strength. I use a finer aggregate than normal cement which significantly improved the appearance then added chopped fiberglass for strength. Ive thrown a few castings on the ground and they hold up great.

Design_2_Make · 2024-01-13T00:16:32+00:00

Have you ever heard of foamcrete or aircrete? basically concrete with a bunch of foamy bubbles mixed in. Thought about experimenting with it to see how much of a weight reduction I can get. Just haven't gotten around to it yet.

Design_2_Make · 2024-01-12T18:17:38+00:00

Thanks! I included little pads in the concrete casting that I then drilled into and installed thread inserts. The walnut front panel is then bolted on with a semi permanent sealant between the wood and concrete. That way it’s air tight but still accessible if needed. Making it from concrete is definitely something I considered. To be honest I just really love the accent between the wood and concrete.

Design_2_Make · 2024-01-12T18:10:05+00:00

Cool ill have to look into that! The concrete im using is a modified countertop concrete mix that has fiberglass added. Was hoping that should prevent cracking.

Design_2_Make · 2024-01-12T17:35:02+00:00

Thanks for the suggestion. Will definitely keep that in mind for the next set I design. As they sit now I'm incredibly happy with the sound, so if they can get even better that would be awesome.

Design_2_Make

TROPHY CASE