Jet Spindle Application Insights: Engraving

During the month of March, Colibri Spindle is focusing on the most common jet spindle speeder applications and giving our partner insights into the best practices for optimizing success.

This article looks at two case studies as well as our Partners’ recommended cutting tools for engraving.

Engraving is an ideal application for jet spindles and process time savings of 6-12X can be achieved, which is the equivalent of saving 50-80% saving in machining time! For engraving and other applications where small, pointed tools are used, higher speeds are required for a quality finish and productive feed rates.

Depth of cut (Ap) is usually less than 0.5 mm and width of cut (Ae) is very narrow as well, usually less than 1 mm. Cutting Edge Angle varies between 45 to 60 Degree. The letters and numbers are integrated to engrave and so what we are looking for are accuracy, speed, and minimal power. Ideal machining requirements for Jet Spindles.

Because the effective Depth of Cut (Dcap), i.e. cutting diameter at cutting depth ap, is much narrower at the cutting point than the diameter of the tool which allows you to use large tools.

Engraving Case Study 1

Data Colibri G-JET Steel 250HB
PRESSURE	25 BAR
FLOW RATE	18 l/min
RPM	30.000 r/min
Cutting Diameter	2mm
Cutting Tool	Spherical cutter with 2 cutting edges
Data:	N= 30.000 RPM/min f= 0,03 mm/turn
Data:	Vf= 1.000 mm/min ap= 0,3 mm ae= 0,5 mm

Engraving Case Study 2

Data Colibri HPC JET Brass
PRESSURE	70 BAR
FLOW RATE	24 l/min
RPM	45.000 r/min
Cutting Diameter	5mm
Cutting Tool	Single Flute Solid Carbide 60°
Data:	N= 37.000 RPM/min f= 0,015 mm/turn
Data:	Vf= 700 mm/min ap= 0,4 mm ae= 0,4 mm

ROI Analysis

Details	Machine Spindle	HPC Jet Spindle
Cutting Speed (m/min)	113	700
Spindle Speed (min-1)	5,995	37,136
Table Feed (mm/min)	90	557
Metal Removal Rate (cm3/min)	0.01	0.09
Cutting Time/Part (sec)	234	38
Total machining cost per part(€)	11.18	4.66