Confirm how to get started with CNC

Driveslayer45

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Good good morning everyone I hope this post is not redundant I've done a lot of reading and believe I understand what I need to get started.

I currently have a p.m. 727v I'm installing stepper motors on the x & y axis for power feed. If I understand correctly I can get started with CNC by ordering a $30 CNC 5-axis controller off Amazon and downloading fusion 360 for hobbyist. While upgrading to ball screws would be best it's not required.

What what am I missing?
 
Not sure which 5 axis controller you are looking at but I think you will also need Mach3/4 or equivalent. You will also be very limited if you don't implement a z-axis. But your basic premise that moving from Power Feed to CNC is not a big step is right on.
 
I have a $20 controller https://www.amazon.com/gp/product/B0093Y897A/ref=ppx_yo_dt_b_asin_title_o04_s02?ie=UTF8&psc=1 I'm using with LinuxCNC http://linuxcnc.org/. In addition to the installing the steppers, which I assume you are powering with some sort of stepper driver like https://www.amazon.com/gp/product/B06XSBB45M/ref=ppx_yo_dt_b_asin_title_o04_s01?ie=UTF8&psc=1 you will need a computer with a parallel port, CNC software such as Mach3/4 or LinuxCNC and the design software (Fusion 360, FreeCad https://www.freecadweb.org/ , etc.), a power supply, and cables to connect everything. There are also many other g-Code rendering programs, not to mention the backlash issues you may encounter using acme leadscrews.

I'm far from an expert on this as my machine is still in the build stages but if you're asking "can I make this machine CNC without spending a ton more money?" then the answer is probably yes. Getting the results you desire may be more involved but there are plenty of folks on this and other forums that have been down this path and will be willing to help.

For me it's more about the learning experience than anything else, you will have to decide if it's worth it for you. You can always just control the stepper motors manually with something like this https://www.amazon.com/gp/product/B07HNSVMVH/ref=ppx_yo_dt_b_asin_title_o01_s01?ie=UTF8&psc=1 if all you need is a power feed system.

Cheers,

John
 
You are going to need some CNC software to run the system. Mach3 is popular and well supported by the user community, but it is obsolete. The $30, 5 axis ''controller'' does not by any stretch control anything, it is simply a device that allows the CNC software to interface with the stepper drives and in many cases with the spindle motor.

Not installing ball screws will seriously hinder the accuracy of the system, but it will work.

Maybe a parts list (with internet links) would allow us to better help you with your choices of hardware.
 
I am a user of Mach 4 (CNC control program running on PC) + Ethernet Smoothstepper (Motion controller talking to Mach 4 and producing motor commands) + Basic Breakout Boards (CNC4PC) + Servo Drives (more complicated but not really different from steppers). I'm happy to comment on the various aspects of this system if you are interested. Fusion360 is a great option for CAD (design) and CAM (machine programming) in one package. It is not the only option (I use Inventor and Mastercam).

You should decide what you hope to do with this. If all you want is a fancy power feed then keeping the ACME screws is fine. If you want a full featured CNC that is accurate, then you should plan on converting all three axes to ballscrews.
 
Ok, i think i confused myself, I thought fusion 360 was for design and running the mill, but fusion 360 designs and makes the gcode that I then put through mach(x) or linuxcnc or something like that to actually control the steppers and make the cuts?

I'm currently running the steppers with a https://www.amazon.com/gp/aw/d/B07QB1MFN4?ref=ppx_pt2_mob_b_prod_image and https://www.amazon.com/gp/aw/d/B07B9ZQF5D?ref=ppx_pt2_mob_b_prod_image

On the z axis, is that the quill or the whole head?
What is I don't have a parallel port, do they have a USB option?
 
That sounds more correct :)

Head vs. Quill is up to you. The quill is very limited in travel so most people do the head. I have locked my quill in place and removed all the gearing.

You can run those drives directly from a motion controller that produces step/dir outputs. Most systems DO NOT use a parallel port these days. Motion controllers can operate from USB or Ethernet (with Ethernet being preferred in most cases for bandwidth and noise immunity).
 
Ok, i think i confused myself, I thought fusion 360 was for design and running the mill, but fusion 360 designs and makes the gcode that I then put through mach(x) or linuxcnc or something like that to actually control the steppers and make the cuts?

That is correct.

What is I don't have a parallel port, do they have a USB option?

Yes
 
Also, if you decide to go with Mach 3/4, I would strongly recommend to pay the little extra and get Mach 4. I am very pleased with how much better it is compared to Mach 3
 
The parallel port is ideal for a synchronous connection between the PC and the CNC, and is the traditional interface. USB/serial requires a microcontroller (smoothstepper) to time the asynchronous connection to the CNC, and that is not a trivial task. A third option, also a smoothstepper based controller, is to use Ethernet. Personally, I am averse to USB for CNC because there is too much to go wrong from PC to CNC. The platform was designed for synchronous data. Timeouts, driver glitches, Windows hiccups, software compatibility, USB TTL voltage differences- all issues with USB. USB requires a driver (and driver support, good luck), where Ethernet and parallel do not. You can install a parallel port to any desktop PC using a $20 PCIe x1 card, or use your existing Ethernet with a smoothstepper, or tackle the headaches of USB if you really want to.

Edit: Don't even think about using laptop USB unless you can deal with driver-level power management and a 3.3v signal when smoothstepper expects to see 5v...
 
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