CNC Router Accuracy

This is a great topic because everybody wants to know how accurate of a machine that they are buying or building. Here is some helpful information to consider.

• Accuracy in any simple CNC machine boils down to one thing. The accuracy of your lead screw or ball screw. There are of course other factors but in the end this is the big one.
• There is also some softwares that allows you to "map" your ball screw so that you can adjust your machine to be more accurate. This is done by almost all CNC manufacturers out there.
• Servo driven machines are no different because they work with a rotary encoder that trusts the accuracy of the ballscrew.
• The other factors that aafect the accuracy of your machine are heat, moisture, wear, tightness of srive components, and backlash in the drive system.
• Here at Modular CNC we handle backlash using a double nut system and a little preload.

I hope this helps explain accuraccy during your machine build.

Thanks, Andy

Getting Started with CNC Routing

Here is a quick guide to getting started in CNC Routers. These are some of the main items you will need.

• Spindle: Harbor Freight 1/4" Laminate Trim Router (2.5" body diameter)
• Shaft Couplers: To couple the motors to the screw shafts look at I have them available on my website. You can also try http://www.mscdirect.com for shaft couplers. You can also find them on eBay as well.
• Electronics package: http://www.xylotex.com/ and others. The type of electronics package you get will depend on your level of electronics experience and what you want to do. I like Xylotex because you can buy a complete finished controller with motors or you can buy just the board and get the other items you need separately (motors, power supply, fan, enclosure, etc.).
• Software: You should use the software that works best with the electronics kit you choose. They will have recommendations.
• PC: You should use the type of computer that is recommended by the software. Some need an older computer that boots in DOS mode but there are others that can run on XP.
• Work Holding: This can be easily accomplished by using a "spoil board" piece or sacrifice piece. You bolt your work piece to the spoil board and then bolt the spoil board to the table top. This allows to cut through the work piece and into the spoil board without ruining the machine top plate.
• CNC Programs: You will need to generate G & M codes to operate your CNC Machine. This can be done in many ways. You can buy your programs form others on the internet, you can hand write code, you can purchase a CAM program that allows you to draw in there software and generate code from that, or draw in a separate CAD program and import it into you CAM program for CNC code generation.

There is tons of info out there on the web just Google CNC Router and Table Top CNC Router. I hope this helps.

Thanks,

Andy