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CNC Routers

(February 2017) posted on Wed Feb 08, 2017

Be a cut above your competition


By Chris and Kathi Morrison

click an image below to view slideshow

Fabricating dimensional letters, POP cut-outs, intricate sign boards, dimensional logos, unique carvings or tearoom-type signs can differentiate your shop from its competition. Such pieces can be created with a jigsaw or bandsaw, or by a skilled craftsman working with carving tools. But what if you don’t have trained staff or the hours required to learn such skills? In reality, producing such work can be stress-free, because a professional-grade, digital/CNC router will cut such work automatically and repeat the process as often as you like. While many CNC router manufacturers offer signmaking machines, there are several things to consider before making a selection.

The router table is the first area to contemplate. Obviously, the table must accommodate the largest material you intend to work with, but also be heavy and solidly built. Next, consider how the material will be held in place during the cutting process. Most tables use a T-slot and clamp method, but many users prefer vacuum system hold-downs, which are effective but add to the machine cost.

CNC routers drive a gantry and its mounted spindle in an X, Y and sometimes Z (up, down) pattern, and because speed, force and accuracy are important, we recommend servo-motor drive systems. You may encounter the term “servomotors” also, which is used to describe servo-motor drives that comprise a closed-loop, position feedback system that corrects departures from the computer-provided cutting path, thus effectively eliminating machine-caused cutting errors.

Most machines use a rack-and-pinion drive for the X and Y axes and a lead-bearing screw drive for the Z axis. Maximum cutting (spindle) speeds vary, depending upon how much you’re willing to spend. Higher spindle speeds (with proper bits) provide faster and cleaner cuts and more media diversity. The router manufacturer should provide a chart that recommends cutting speeds and bit-depths for machine-endorsed materials, and also gives you pre-purchase decision points so you can be sure the router will process the materials you intend to use.

We like automatic bit and tool changers because they speed production. In addition, we believe a dust collection system is worth the extra cost. Cutting wood, HDU and other porous sign materials creates dust that can create both health and fire hazards, as well as a mess to clean up. The elephant in the room is how to translate the design into a final piece. The good news is that most signmaking packages will export 2-D designs that will cut just fine, but relief cutting requires a 3-D sign package. Further, many machines are equipped with handheld controllers for setting the machine’s starting point and may even cut preset objects with line circles, rectangles and more. However, to produce unique signs, your design software must be compatible with the router’s CNC drive system.

Finally, if you want cut sign boards or dimensional letters and your shop volume isn’t overwhelming, a lower-cost router should do the job. If you plan to produce many pieces and want to combine cutting, engraving and intricate 3-D relief work, then research the more sophisticated machines. Whichever you chose, a CNC router will be a great addition to your shop.

Routers pictured at the beginning of this post:

Maestro by Delta
by AdamsTech
channelbender.com

APEXZ3R
by MultiCam
multicam.com

100 Series 6x12
by CLN of South Florida
clnofsfl.com

Accu-Cut
by Computerized Cutters
computerizedcutters.com

Pacer 4008 ATC
by AXYZ Intl.
axyz.com

Gerber Sabre
by Gerber Technology
gspinc.com


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