Protocase Resources

The information below is intended to be helpful for customers who wish to learn more about enclosure design. Also, please use our online support if you have questions for our expert design staff.

 

Frequently Asked Questions

CNC Milling

What is CNC Milling?

CNC Milling is the removal of metal with a rotary cutter or other rotating cutting tool. Our 3-axis milling feature a 30,000 RPM spindle which allows us to cut at high speed with smaller cutters, and features an automatic tool changer which decreases total time to cut a part.

How large of a part or panel can be CNC machined?

The maximum size sheet metal parts we are able to mill in a single setup is 4' x 8'. The maximum size bar stock that we are able to mill in a single setup is 26" x 16" x 12".

What is the smallest part or panel that can be CNC machined?

The minimum sheet metal part that can be vacuum-chucked without clamps is 5" x 5". Vices can be used for smaller parts. Please email info@protocase.com for more details.

What materials can be CNC machined?

The minimum sheet metal part that can be vacuum-chucked without clamps is 5" x 5". Vices can be used for smaller parts. Please email info@protocase.com for more details.

What materials can be CNC machined?

CNC milling is most commonly performed on aluminum (3/8" Alum 6061-T651 48.5"x96.5" and 1/2" Alum 6061-T651 48.5"x 96.5") and copper. Steel and stainless steel may also be milled, but cycles are longer due to the inherent cutting characteristics of these metals.

What is the tolerance of your CNC machining?

We offer a range of tolerances between +-0.001" and +-0.005" on standard jobs, however this can vary for certain designs. For more information, email info@protocase.com.

Can I use self-clinching fasteners in my CNC machined design?

Yes. Machined parts are generally used with concealed head PEMSŪ (whereas sheet metal is generally used with through-hole PEMSŪ). Inserting PEMSŪ into blind holes has the extra benefit of a smooth finish on the opposite sides of sheet metal after the fastener is installed.

These PEMSŪ can be used in sheet metal as thin as 0.075". View our CNC Milling page for a full list of stocked self-clinching fasteners for blind milled holes.

What kind of a finish does CNC machining leave?

Due to the spinning motion produced by the CNC milling machine’s cutter, the surface finish of CNC machined parts will have visible toolmarks. If you require a smooth, unblemished finish to your part, we recommend choosing a secondary finish: grained finish (can only be applied to the outside of machined enclosures due to geometry) or powdercoat.

Can CNC machined parts be powdercoated?

Yes. All of our stock powdercoat colors are available for powdercoating CNC machined parts as well (non-stock powdercoat colors are available with additional cost and lead time). Powdercoat paints with texture (Sandtex Polyester and Textured Polyester) will cover toolmarks with no additional finishing operation. Non-textured paints (Smooth Polyester, Smooth Epoxy and Smooth Polyester-Epoxy Blend Hybrid) will not cover toolmarks, therefore an additional finishing operation such as grained finish will need to be performed before powdercoat painting.