CNC engraving machines work great for when you want to engrave into metals with cuts more than a few thousandths deep. This is opposed to the process of burnishing or dragging on metals. Using CNC engraving machines to engrave into metal presents end users with a variety of options to consider prior to production.

When using CNC engraving machines to engrave into metal, first think about how you are going to hold the material. Engraving into metal will most often exceed the strength capacity of tape or holding mats. Ideally, you want the holding device to completely keep the material from moving as well as be easy to use. You need to be able to set and move the material as efficiently as you can without sacrificing your hold or damaging the material.

Custom Jigs

If you’re using CNC engraving machines for highly competitive work, you really should design a custom jig that’s specific to that job. A good jig will allow you to quickly, easily and accurately place the material for multiple engravings of the same job. It’s worth spending some extra time and money creating a jig that makes it easy to hold and remove the material.

Cutters, Cutting Fluids and Spindles

Engraving into metal quickly eats up cutters. You really should use standard engraving cutters that are designed for engraving metals. Double ended, double fluted end mills work best. You’ll find end mills deliver a much superior quality and are easy to use. No matter which style of cutter you use, keep many duplicates on hand for replacement of broken cutters and re-sharpening. If this is a big part of your business, do yourself a favor and purchase your own cutter sharpener.

Definitely use a cutting fluid. Using a cutting fluid to lubricate the cutting surface will help to cool and protect your cutters. This also helps produce a smoother finish to the cut. Mystic Metal is a great cutting fluid that’s available through most suppliers.

Arming your CNC engraving machines with a collet spindle is essential for this type of engraving. You’ll notice that standard top load spindles don’t have the support necessary at the bottom of the spindle, causing the cutter to chatter under large engraving loads. This severely limits your engraving quality as well as damages the machine.

Z-Axis Speed

It is a good idea to use a slower Z-axis speed when engraving stainless materials. This gives the cutter time to fully penetrate the material to the desired depth before moving laterally. You can always adjust the speed of the Z-axis during production for the CNC engraving machine as needed.

Challenges and Considerations

Rotary engraving on stainless steel is a challenging application with CNC engraving machines. Yet stainless steel is a frequently requested material due to its low maintenance, heat resistance and inert properties.

It’s critical that those using CNC engraving machines understand that planning the production of the job is very important. Using the proper tools and fastening devices can make a project run efficiently and effectively.

Joe Marziano is Vice President of Vision Engraving and Routing Systems – the largest manufacturer of engraving machines in the United States. For more information about CNC engraving machines and more, please visit our site.