Carbide Coated Drill Jig Bushings

Carbide coated drill bushings are steel bushings with a .0003 thick tungsten carbide coating on the inside diameter of the bushing. This produces a wear resistant surface that greatly extends the life of the tool. I.D. tolerances of .0003 can be maintained.
Carbide coated bushings may be the ideal solution to many of your machining problems. When coated bushings replace standard steel bushings tool life can be increased up to 10 times, depending on the application. By maintaining tight tolerance and surface finish specifications, your tooling usage will not increase. Performance approaches and sometimes exceeds that of solid carbide bushings.
The very best application is when the bushing is drilling at an angle. Carbide coated bushings will outperform solid carbide in this situation. When a solid carbide bushing is ground at an angle, at the exit end, a sharp edge is created. This edge can chip or break resulting in excessive drill margin wear. Carbide coated steel bushings do not fail in this manner.
A good performance example comes from a major auto manufacturer.  They were using solid carbide bushings to drill oil holes at 45 degrees, in a crankshaft. Bushings were changed daily. Upon switching to carbide coated steel bushings the usage dropped. Bushings then only needed to be changed every 10 days. The cost savings was significant. Another advantage of carbide coated bushings is cost and delivery. Price is generally 60% that of solid carbide. Delivery is 3-4 weeks compared to 5-8 weeks of solid carbide. Rush deliveries are available.
Carbide Surface Company owns and operates Colonial Bushings Inc. Colonial Bushings has been producing high quality drill jig bushings since 1929.