4x4 CNC Mill

The 4x4 CNC Mill is a CNC router/mill in the Wood Shop. It has a 4' x 4' (1.2 x 1.2 m) cutting area and about 5" (130mm) vertical range. FamiLAB members built it based on Joe’s 4x4 Hybrid CNC Router with considerable customization.

Process Overview

• On the computer, create a 2D or 3D geometry.
• On the computer, run Vcarve, pull in the geometry file, create the toolpath from the geometry, then write the G-code file.
• On the router, set up the workpiece and install the router bit. Start the router equipment.
• On the computer, run the Mach4 software, pull in the G-code, set up the toolpath and machine settings.
• Turn on the router spindle and dust collection.
• On the computer in Mach4, run the G-code program.
• Remove your workpiece. Remove the bit & clean the collet. Clean up the table, floor, etc.

Stats

• 4x8' cutting area (slightly larger, to reach the edges of the board).
• 20,000 RPM router.
• Collets for 1/8", 1/4", 3/8", and 1/2" shank tooling.
• HFS8 hold-down slotting.
• 300 in/min (125 mm/s) top speed.
• Mach4 software control, with servo-driven axis.

Rules

The CNC is expensive and FamiLAB members have put a lot of work into it. We need to keep the machine running in the best condition so everyone can enjoy it. These rules are strict for a reason - to encourage careful, responsible usage of a large piece of equipment.

• Do not run the machine unattended. The machine has the capability to quickly destroy itself, bits, clamps, drive systems, etc. Stay near the machine at all times it is running a program and be ready to E-stop if an issue arises
• If something is broken, TELL SOMEONE. If you broke it, if someone else broke it, if you SAW someone else break it, make it known in the #woodshop-cnc channel on Slack. Breaking it and leaving it without telling anyone will result in you not being able to use the machine anymore.
• If you ruin something, replace it. If you damage a clamp, if you ruin the spoilboard, if you break a lab bit, if you damage a collet, you are expected to fix or replace it. If you are not able to do so, ask other members in the #woodshop-cnc channel for options. We keep some spares on hand but these are not consumable items. If items keep becoming damaged, they will no longer be available and you will have to provide your own.
• If you do not know 100% how to do something, ASK. If you are not sure how to set up a job, how to run the machine, etc. then ASK. If you negligently damage the machine, it is expected that you assist with repairs (financially or otherwise).
• If something does not look right, STOP. Be ready to halt the machine if something does not sound right, smoke appears, bad noises are heard, movement is not correct, etc. Run a simulation on every cut. Keep feed rates very slow when starting a new (unproven) program to make sure you have time to hit a stop button if something goes awry.
• CLEAN UP AFTER YOURSELF. The CNC is not to be run without the dust collector on and the dust shoe in place. If for some reason you need to run a test cut without dust collection, you are required to vacuum the entire machine afterward. Cleaning up includes removing dust from your cuttings and the table. Do not leave the table a mess. A flexible hose connected to the dust collector is available. USE IT. Do not leave cuttings and swarf on the table or leaning against anything. The CNC is not a storage bin.
• Put all tools back when you are done. Keep all bits in their holders as they are very sharp and dangerous. Put all tools back in their proper place. Remove collets and put them back in storage.

Usage

• Darkmoonsinger's excellent writeup
• Additional notes in this forum thread
• "CNC 101" class presentation. NPolansky created in Jul 2016. Covers 4x4 CNC Mill, Haas VF-1 CNC Mill, Vcarve software, Fusion 360 software, CNC operation, etc.

References & Experts

CNC Experts: Nick Polansky; chorca; circuit.
G-code Experts: Dave Smith.