This type of retention knob is fit for the CAT40 CNC machine of Fadal,Hurco,Mazak,Okuma

The retention knob is a key ingredient not only to the overall performance of the tool holder and cutting tool life,

but also to maintain a safety standard on any machine shop floor. We choose SNCM420 (SAE 4320) alloy steel,

with high nickel alloy content, for its high tensile strength to withstand strong centrifugal force, high load force,

high feed rate, and difficult-to-machine material in the era of current CNC machining environment. The ultimate

tensile strength of SNCM420 alloy steel is 980 MPa and our material is made in Japan by a very reputable steel

manufacturer.

To maintain the tight tolerance of key dimension on a retention knob, we integrate the Marposs Unimar S

measurement head which has a repeatability within 0.1 micron into our grinding process. To further maximize

production output, we utilize robotic arms to load and unload a retention knob bar stock into a CNC grinder.

Additionally, our retention knobs are roll threaded which provides higher strength and excellent thread quality,

compared to others which are cut threaded.

Concentricity

Concentricity is inspected with a Mahr Millimess 1003 Dial Comparator which has a 1 micron (um) graduation

and 0.5 micron (um) repeatability to ensure each batch production of the retention knob is true to the spindle

center line. 

Optical Measurement

A critical dimension on every retention knob is the height of the loading contact point and the height of un-loading

contact point. When this two dimensions are not within tolerance, there could lead to improper engagement with

main spindle and even cause severe damage to the retention knob's rigidity. This two dimensions are inspected on

an optical tool presetter that is made in Italy by a world-renowned manufacture and measurement are monitored in

micron (um).