An Investigation Has Been Carried Out To Study The Feasibility Of The Use Of Closed-Field Unbalanced Magnetron Sputtering (Cfubms) Technology For Reactive Sputtering Of Tin Coating On Both Hss And Cemented Carbide Tool Substrates. In The Preliminary Investigation, The Dependence Of The Substrate Ion Current Density On Substrate Bias Voltage And Process Pressure Was Determined. Also, The Results Of Preliminary Investigation Clearly Exhibited The Potential Of Tin Coating Produced In-House In Enhancing Both The Anti-Welding And Anti-Wear Properties Of The Cutting Tool. During The Study Of Effect Of Process Parameters, Some Interesting Facts Were Revealed. While The Growth Rate, Grain Size, Lattice Parameter, Density Of The Coating, Compressive Residual Stress, And Microhardness Were Found To Increase With Cathode Current, There Appeared To Be An Optimum Value For The Same For Maximization Of The Coating-Substrate Adhesion. Within The Working Range Of The Present Cfubms System, Variation Of Substrate Temperature From 250 Oc To 450 Oc Did Not Cause Noticeably Wide Variation In The Coating Characteristics Except The Grain Size Which Showed Progressive Increase With The Increase In Substrate Temperature. The Most Noticeable Effect Of Substrate Bias Voltage Was The Reduction In Coating Thickness After A Particular Value Of Bias Voltage. Microhardness And Coating Adhesion Have Been Found To Improve With Increase In Negative Bias Voltage. However, After A Particular Value Of Bias Voltage, Further Increase Was Counterproductive For Both Microhardness And Adhesion Of The Coating. The Adhesion Strength Of The Coating Deposited On Carbide Inserts Has Been Found To Be Affected By Coating Thickness. This Was Also Reflected In The Machining Performance Which Indicated An Optimum Coating Thickness For Better Resistance To Wear. One Of The Most Important Observations Of The Present Investigation Is The Remarkable Improvement In The Resistance To Wear Of Uncoated K-Type Carbide Insert In Steel Machining When It Was Coated Just With A 4 Μm Thick Tin Film. Also, It Was Found That Chemical Pretreatment Of The Substrate Was Beneficial For Resisting The Growth Of Crater Wear But Detrimental To The Flank Wear Behaviour Of The Coated Tool. The Present Investigation Clearly Indicates That By Proper Optimization Of Process Parameters Including Those For Substrate Surface Preparation, There Is Ample Scope For The Improvement In The Physical, Mechanical, And Functional Characteristics Of The Coating Produced In-House To A Level Which Is Comparable With A Proven Tin Coating Technology.