David Orlo Centered XYZ 3D Mockups

These are the original 3D mockups illustrating the key differences between Rev.1, Rev.2, and Rev.3 of the Centered-Z Mod, also known as the X-Symmetry Project by David Orlo.

What is 'Centered XYZ' ?

• Arguably the most important thing to get perfect in FDM 3D printing is?
• Your first layer, and everything that supports a perfect first layer. Otherwise, the print will fail or just look like crap unless the infill is sparse enough to 'fudge it' and make it work.
• The 'Centered' idea came to me when trying to find a better solution for the cartesian style printers to handle Z movement.
• Both single and dual Z-Lead have their drawbacks. I realized a single 'driver' was important,
• You could have Dual-Z leads, with a good design and a single stepper driving them, and I'd imagine it would be pretty solid if dialed in correctly
• Or you can use my design and files and about 1/8 of the parts over a dual-z, and less setup, less constant tweaking / upkeep, less times pulling your hair out because 'it all just sucks'

Why 3 Revisions instead of just one?

• I took the time to create 3 distinct versions from the very beginning, in an attempt to appeal to the largest number of users possible, while sticking to standard cartesian style printer with a lead screw (or two)
• The first version allows you to use nearly all of your standard printer parts that came with the printer along with a few purchased parts and/or a few printed. This stage is reversable easily over a weekend (slow down, do shit right!)
• The second version moves closer to the final vision with the through-hole stepper motor (cheap but sometimes hard to find exact lead screw specs local in the US, under $20 on Ali Express) THEY DONT NEED TO BE POWERFUL.
• FYI: They could prob be the same rating as your current Z stepper AND still carry twice the load while using a different Z lead AND still run cooler AND move twice as fast.
• Yes, seriously. I'm even low-balling
• The third version is the final concept (I think.... linear-rail centered-z anyone?). This is what I envisioned when I started out, staring at my printer and screaming WHYYYYY in my head. I think I know the 'WHY's' I had at the time, keep reading.
• The third version includes a bunch of 3D models to fit a wide range of printers and reduce issues finding the right parts, brackets, etc.

Which version should I start with?

• This is a tough question because I don't know what you're starting with and what your desired end result goals and budget is
• The whole point of the first revision is to let people see firsthand how great it can be while only requiring a few screws, a couple pieces of printed plastic and the ability to reverse the changes
• Rev 1. will help fix leveling / tramming issues and overall increase the reliability, repeatability, speed, etc.... all the good stuff. While mostly costing only time to perform the mod and adjust your printer config (need to reverse Z step direction)
• Rev 2 is great if you started with Rev 1 and aren't ready to upgrade to linear rails (if you don't have them currently), or you are still undecided but want to see what the mod is like with intended through-hole Z-Stepper.
• Rev 3 is the recommended version and this goes doubly so if you already own linear rails.

How is this possible?

Why hasn't it been done before?

Why am I/you just now hearing about it?

• First, I'd like to address what I think is the biggest factor in the aforementioned questions, which in short is China, but not in the way Trump says it. It's really not that serious, here are the details and why I came to this conclusion.
• The TLDR on it is, lack of incentive to innovate and redesign from the ground up. Thinking so far outside the box, that the box is now a spaceship, hop on, we all sit outside it now.
• Seriously though, and I mean no offense by this, but China products have a track record of being cheap, lacking innovation, cloning, betting on 'Safe' market strategies and so on.
• About the only time you see something new come out of one of these big Chinese 3D-Printer companies is when they are copying someone else, and that's only as a survival strategy for their business.
• Don't take my word for it, just go look at the code that runs on any of them, or take a look at all the corners cut, just to save .01 or two cents. And that's regardless of the headaches and inconveniences the money pinching causes in the process.
• After thinking it through, I'm far less surprised I came up with this now, so many years after 3D printers have been on the market and changed through those years.
• The other big reason is standardization and component procurement.
• When 3D printers for hobbies were first made, they used common supplies you could purchase from a hardware store, and that still shows today in many 3D Printers, even some of the biggest brands.
• This is cool and all, I mean to just get it done, but there is no replacement to a bespoke application of sorts.
• I had the desire to follow standardizations and commonly available hardware whenever possible, while attempting to reduce part count without compromising the design or inflating costs.
• This also meant eliminating custom parts that couldn't be printed while giving users the ability to purchase the parts in a different material (using the same 3D files)
• The motor brackets generally have a 'print or purchase' option, however the purchased metal brackets and plates will be a general / universal design that's meant to cover many use cases so it may be 'more' than needed to get the job done.

Additional Resources:

• View my other designs for complete printed part downloads.
• For more details, instructions, and the Wiki, check out the project on GitHub:

GitHub: X-Symmetry Project - Centered-Z Mod

This object was created using Tinkercad.
Edit it online: Tinkercad - David Orlo Centered Z Mod