I’m Xavier, in professional retraining in woodworking.
I have small knowledge about CNC, have done some small project in fablab, and shared workshop, learning fusion, etc.
I would like to build a first CNC and love your project for a while.
Do you have any ressource regarding the design of some part of CNC ?
I’d love to find a video of Ryan explain why he chose this gantry design over this one, or a post, article, podcast.
Why nema 17 is enough for this kind of stress, where are the pro and cons of this design over this one, etc. How the squarness of the lowrider is obtain ?
I’m was reading the response of Ryan regarding the design of another CNC in this post /t/indymill/20268/2 (oups i cannot post a lilnk in my post) and rhooo i would love to read or watch things about why the design of the lowrider is for 1,5‘‘ cut deep maximum. How to not over constrain things with ball screw or why belt is enough for lowrider cutting aluminum.
Sorry i’m not fluent in writing english but i read it better.
That is not an easy ask. You want me to explain all my design choices? That just is not really feasible.
The design has evolved over the last 9 years. I get feedback from real users, adjust, and redesign. The design goal of this machine is best bang for the buck, with the goal of an experienced user being able to mill out aluminum parts all while keeping the parts easily accessible worldwide. As commodity parts evolve, so does the design.
If you think it might not be enough of a machine have a look at the real users projects, Topics tagged gallery-lowrider-cnc, Topics tagged gallery-mpcnc. What I have to say is not actually very valid, my income depends on these machines I could say anything I wanted to upsell it. I prefer to let others projects show what is possible by an actual user, not the designer of the machine.
Most CNC designs that I’ve seen follow the old-school moving gantry design, which seemed to follow from the manual milling machines. The MPCNC line changed that mold and it seems to me the 3" Z was natural there as a feasable maximum to retain rigidity when doing through cuts. That of course comes from my perspective outside the designer’s point of view.
The LR seemed to imherit that Z span, as is reasonable. In this case, at the top of travel. I have had no problems stemming from increasing that Z travel to the 5" range, but I am also not using the LR3 for particularly hard materials. Also the LR3 design doesn’t penalize the increased maximums the same way that the Primo does. Anything I do that could have been done with the original Z range carries no significant rigidity penalty as it would with the Primo.
I learned a lot about the designs by building and using the CNC machines. I believe that I could design a capable machine after having built and modified these, plus reading the cnczone forums. Pretty sure that I could design one with more expensive parts that could work faster, if I wanted tonspend the money, but “bang for the buck” I wouldn’t be able.to beat V1 machines by much. Any gains I could make would be because of localized availability of things that I can get here, but maybe you can’t get a good deal on. Ryan specs parts almost anyone can get their hands on easily, or can get variants on. (Ie: 23.4" conduit or 25mm tube or 25.4mm tube to accomodate different markets.) The 608 skate bearings, nuts, bolts, and screws are all commonly available world-wide, even the MGN12H linear bearings, TR8 lead screws and nuts are all commodity parts available everywhere.
Many thanks for you reply.
I wasn’t expecting one from the founder, i’m honor, thank you for you project and for your time.
I’ll build a LR3, just a tiny one for my small flat (hope the neighbour will accept the noise).
I’ve also noted cnczone forum in my research, i will dig in it for my quest for informations.
It’s not that i want to make a new build or something, i just want to understand more about the mechanical chalenges. I was thinking that maybe i miss a ressource, where someone talk about all those aspect with price in the game: torc/speed of different nema 17/23, why you trasnfer the force with belt, lead screw, ball scew, rack and pinion, why you chose wheel, linear rail, cost/benefit implied, fixed gantry vs moving one like you mention, etc.
But you reply for a part, thank you, have a nice day/night
I enjoy building the machines myself as a hobby. Which also means I mod my machines as I see interesting ideas. I’ve now built an MPCNC, LR3, and a couple of 3D printers.
In every case, the designer’s choices became a little clearer. I also go through a period where I watch the machine work and that is also helpful. I didn’t truly understand the LR3 until I had watched my MPCNC struggle with my projects.
Which brings me to my point. I think each person’s workflow is an intersection of their projects/work and their machine. You may not completely understand your own preferences until you throw your workpieces onto a machine and get a chance to try it. A 2x4 LR3 is an awesome place to start. It’s a journey.
If I now chose to go buy a CNC machine, I now feel like I understand what I’m looking for. However, I also enjoy the feeling that I’m confident my LR3 is meeting my current needs (as a hobbyist, speed is a luxury.)
One last comment. I have wondered about the things you mention from time to time. But spindle size, weight and capability is now something I research. If I were starting a new machine of my own design (I’m not ), I’d ask what bits I need for my projects, and what spindle will drive them. Then I’d work backward out to the motion system, which is really enlightening. (One of the observations I’ve made on my equipment is that my old MPCNC (dismantled for space purposes) was probably a little bit better motion platform for my diode laser, Whereas my LR3 is a much better motion system for sheet good cutting with a router (the bulk of my use.))
), I’d ask what bits I need for my projects, and what spindle will drive them. Then I’d work backward out to the motion system, which is really enlightening. (One of the observations I’ve made on my equipment is that my old MPCNC (dismantled for space purposes) was probably a little bit better motion platform for my diode laser, Whereas my LR3 is a much better motion system for sheet good cutting with a router (the bulk of my use.))
