CNC System Diagram

Updated 10/26/2009

This post will be a sticky post since I expect this diagram to change as I learn more about what I am doing.

CAD/CAM Workstation

I will be using an existing PC to create 2D and 3D geometry using CAD and other applications. This system will also host any CAM applications used to program tool paths and to generate the G-Code files. The resulting files will be transfered to the CNC Controller by sneaker-net or using our wireless network.

CNC Controller

I am most uncertain about this portion of the system. As best I can tell the "CNC Controller" will consist of a PC running CNC Controller software, such as Mach 3, and a hardware controller box that has a Power Supply, a break-out-board and stepper motor drivers. I have more to learn about the function of the break out board but it includes isolating the PC from the high current and voltage being sent from the drivers to the stepper motors.

The Controller PC and Controller Box are connected through a parallel interface. I am planning to dredge out a decommissioned mother board and CPU from the closet and build up a PC dedicated to this CNC Controller function. I have a spare NEC LCD monitor for this system. These will live in the garage/shop with the controller box and router.

Stepper Motors

The stepper motors are connected by cables to the controller box drivers. Depending on the router design there will be either 3 or 4 stepper motors. The Y axis can be driven by dual motors or a single motor.

Machine Tool

The stepper motors are attached to the machine tool and its lead screws. The rotation of the lead screws move the gantry and carriages which hold the router spindle along their axis.

Alibre Design Deal - To Good to Pass Up

I need to confess - I began investigating things regarding this project before I started this blog. Sorry, for the time being I am a few weeks ahead of my readers. The good news is that for now I have few, if any, readers - so no harm done. I figure I am pretty much writing posts to myself at this point. Nonetheless the deal described below expired about a week ago.

While grousing around the Internet for all things CNC I came across a reference to a 3D Parametric CAD product called Alibre Design. I googled 'Alibre' and found alibre.com. As is typical for CAD software they offer several levels of their product, each package having additional features at a higher price point. Alibre Design is their basic system, which regularly sells for $999, plus any ups and extras you might want to add. Alibre seems to be positioned as the value player against competitors like Solidworks.

I guess the recession has not been good for CAD vendors. Alibre management apparently decided to shake the market up and make a play for market share prior to the release of version 12 of the product. For about a month they offered Alibre Design 11.2 for $99. Basically they knocked a 9 off their regular price.

I investigated the feature set and gave it a few minutes of sober thought. OK, enough of that - I whipped out the credit card and down loaded Alibre Design 11.2 and in doing so incurred my first project expense ($99). Thus, I put the first piece of my mini-CNC manufacturing enterprise in place. Ordinarily I would not have chosen to have my first purchase for this project be a 3D feature-based CAD system , but I figure you need to take advantage of an opportunity when it presents itself. Alibre's marketing tactic certainly worked on me, probably to the eventual disadvantage of Rhino 3D.

I have been going through some of the tutorials and other things to get acquainted with my new Alibre software. So far I have been favorably impressed with both the power AND usability of the product, which is saying quite a bit since CAD systems are infamous for having a steep learning curve.

I will post more about my experience using Alibre Design when I start to define 3D geometry for the CNC router to chew on, maybe a guitar neck contour or a plantation shutter project.