Hand deburring and manual polishing are the bane of many machine shop’s and machining department’s existence.  What can be done to minimize the need for these tedious, time-consuming, labor-intensive production bottlenecks?  In many cases, the need for hand-deburring operations can be reduced greatly with high-energy and high-intensity isotropic finishing operations.  See below several examples below where laborious deburring procedures have been reduced or eliminated.

For additional information, technical assistance or help in arranging for free sample processing of your parts contact:
Dave Davidson | dryfinish@gmail.com | 509.230.6821 | http://dryfinish.wordpress.com
titanium knee
Titanium Surgical Implant parts are processed with Centrifugal Isotropic Finishing to replace hand polishing and finishing


Hands-free deburring and finishing. Before and after surface condition with on titanium test specimens.  The upper part in the photo fly cutter milling machine marks and stepovers.  Bottom part shows machining marks removed and replaced with isotropic surface from centrifugal isotropic finishing


Precision Isotropic
Stainless steel castings often require substantial amounts of hand grinding work to smooth and polish surfaces.  In this case, all of the hand-work was eliminated by processing the parts with centrifugal isotropic finishing.



BV crown and pinion B4 2-17
High-Performance Race engine parts prior to Isotropic Micro-Finishing [Photo by Mark Riley, BV Products]
BV gear and pinion after 2-17
After Isotropic Micro-Finishing parts exhibit low micro-inch surface profiles.  The ultra-smooth surfaces improve bearing load, reduce friction, improve lubrication distribution, reduce operating temperatures and extend the service life of components. This type of processing is used extensively throughout the motorsports racing industry [Photo: Mark Ripley, BV Products]

brass coupling
Centrifugal Isotropic Finishing is used to smooth and polish these brass coupling components obviating the need for hand polishing operations.
Centrifugal Isotropic Finishing has been used to minimize hand smoothing and polishing for AM and 3D printed part applications.
Prior to the adoption of centrifugal isotropic finishing techniques small parts such as this required considerable hand-deburring or hand polishing to meet customer requirements.
Prior to using centrifugal isotropic finishing the machine shop making these parts had to handle each one individually through a series of hand deburring and hand-smoothing steps to eliminate machining marks on these medical parts that are used as a medical device inside body cavities
DENTALpart polished-cbf machine
Dental devices such as this one often required many hours of hand-work to make surfaces acceptable for patient use.  Much of that has been automated with the used of centrifugal isotropic polishing techniques.
316 ss casting
Prior to adopting centrifugal isotropic polishing techniques these stainless steel cast ornamental parts required substantial hand grinding and polishing

Prior to adopting high-intensity isotropic finishing methods parts such as these would be edge-finished, smoothed and polished by hand or manual procedures

architectural brass rails
Brass ornamental parts such as these were commonly hand-finished before isotropic micro-finishing processes permitted automation or mechanization of the smoothing and polishing requirements.
Prior to utilizing a fixtured isotropic micro-finishing process these types of musical instrument parts required substantial buffing operations.
milled pocket-001
Smoothing the machining/milling marks and step-overs in the pockets of this veterinary pharmaceutical molding plate posed several challenges.  When the machine shop used hand-smoothing methods to do this the surface tolerances were taken out of spec and parts were rejected.  A hands-free isotropic finishing method was devised that removed machining marks and left completely uniform smooth surfaces.

Parts with intricate geometries often require substantial handwork to access fine features and details, high-intensity isotropic micro-finishing makes it possible to use very finely divided abrasive and polishing materials for accessing intricate details.

Again, high-intensity micro-finishing permits fine edge and surface finish work to be developed for parts that might otherwise require manual methods for finishing.

Aerospace rotating hardware such as these parts can require enormous amounts of hand deburring operations which can be alleviated with high intensity dry isotropic spindle finishing methods.

Non-metallic parts such as these are often hand-finished and hand-polished unless isotropic finishing methods are adopted to automate the processing

These titanium orthodontic wire-forms are polished in special dry process media to produce highly refined and polished surfaces to go against the tender tissues to be found in the mouth.

Much hand-work has been replaced on the final surfacing of these acrylic and alloy dental components with centrifugal isotropic finishing
small titanium parts finishing

SS castings spoons
Isotropic micro-finishing was used to produce ultra-smooth polished surfaces on these stainless steel castings with a minimum of hand-work

Rough ground and sharp edged rotating components such as this can be deburred and finished with high-intensity dry spindle finish processing eliminating hand work that can produce significant reject and rework problems

Cast and Machined Alloy Steel Handgun Slides

Centrifugal isotropic finishing makes it possible to produce refined ultra-smooth surfaces in a hands-free environment.  An added plus is that these processes can produce surfaces that are particularly useful as substrates for a wide variety of coatings.


High-speed and high-intensity isotropic micro-finishing equipment makes it possible to add value to many manufactured components by producing high-quality surfaces often in entirely hands-free automated operations.

For additional information, technical assistance or help in arranging for free sample processing of your parts contact:
Dave Davidson | dryfinish@gmail.com | 509.230.6821 | http://dryfinish.wordpress.com


Mass Finishing technology for deburring, finishing and polishing of machined and manufactured parts and components

Centrifugal isotropic Finishing

Centrifugal Isotropic Finishing (CIF) is a high-energy finishing method, which has come into widespread acceptance in the last few years. Although not nearly as universal in application as vibratory finishing, a long list of important CBF applications have been developed in the last few decades.

Similar in some respects to barrel finishing, in that a drum-type container is partially filled with media and set in motion to create a sliding action of the contents, CBF is different from other finishing methods in some significant ways. Among these are the high pressures developed in terms of media contact with parts, the unique sliding action induced by rotational and centrifugal forces, and accelerated abrading or finishing action. As is true with other high energy processes, because time cycles are much abbreviated, surface finishes can be developed in minutes, which might tie up conventional equipment for many hours.

Centrifugal Barrel Finishing principles – high-intensity finishing is performed with barrels mounted on the periphery of a turret. The turret rotates providing the bulk of the centrifugal action, the barrels counter-rotate to provide the sliding abrasive action on parts.

The principle behind CBF is relatively straightforward. Opposing barrels or drums are positioned circumferentially on a turret. (Most systems have either two or four barrels mounted on the turret; some manufacturers favor a vertical and others a horizontal orientation for the turret.) As the turret rotates at high speed, the barrels are counter-rotated, creating very high G-forces or pressures, as well as considerable media sliding action within the drums. Pressures as high as 50 Gs have been claimed for some equipment. The more standard equipment types range in size from 1 ft3 (30 L) to 10 ft3, although much larger equipment has been built for some applications.

Media used in these types of processes tend to be a great deal smaller than the common sizes chosen for the barrel and vibratory processes. The smaller media, in such a high-pressure environment, are capable of performing much more work than would be the case in lower energy equipment. They also enhance access to all areas of the part and contribute to the ability of the equipment to develop very fine finishes. In addition to the ability to produce meaningful surface finish effects rapidly, and to produce fine finishes, CBF has the ability to impart compressive stress into critical parts that require extended metal fatigue resistance. Small and more delicate parts can also be processed with confidence, as the unique sliding action of the process seems to hold parts in position relative to each other, and there is generally little difficulty experienced with part impingement. Dry process media can be used in certain types of equipment and is useful for light deburring, polishing, and producing very refined isotropic super-finishes.

Below are some process video footage demonstrations of high-speed centrifugal isotropic finishing.  These automated edge and surface finishing methods are capable of producing very refined low micro-inch surfaces that can improve functional part performance and service life.


Further reading:  Internet resources

(1)  “Isotropic Mass Finishing for Surface Integrity and Part Performance”,  Article From: Products Finishing, Jack Clark, from Surface Analytics, LLC and David Davidson, from SME Deburr/Finish Technical Group, Posted on: 1/1/2015, [Barrel, vibratory, centrifugal and spindle finish can improve part performance and service life.]  http://www.pfonline.com/articles/isotropic-mass-finishing-for-surface-integrity-and-part-performance

(2)  “Turbo-Charged Abrasive Machining Offers Uniformity, Consistency”  Article From: Products Finishing, by: Dr. Michael Massarsky, President from Turbo-Finish Corporation, and David A. Davidson, from SME Deburr/Finish Technical Group.  Posted on: 6/1/2012.  [Method can deburr, produce edge contour effects rapidly]  http://www.pfonline.com/articles/turbo-charged-abrasive-machining-offers-uniformity-consistency

(3)  “Turbo-Abrasive Machining and Finishing”. MANUFACTURING ENGINEERING – Aerospace Supplement, by: Dr. Michael Massarsky, President from Turbo-Finish Corporation, and David A. Davidson, from SME Deburr/Finish Technical Group. [Method first developed for the aerospace industry can improve surface integrity and part performance]  http://www.slideshare.net/dryfinish/turboabrasive-machining-me-aerospace-supplement-reprint

(4)  “The Role of Surface Finish in Improving Part Performnce”, MANUFACTURING ENGINEERING, by Jack Clark, Surface Analytics.com and David A. Davidson, from SME Deburr/Finish Technical Group.

(5)  “Free Abrasives Flow for Automated Finishing”, MANUFACTURING ENGINEERING, , by: Dr. Michael Massarsky, President from Turbo-Finish Corporation, and David A. Davidson, from SME Deburr/Finish Technical Group. [Exciting new methods of surface finishing that go beyond deburring to specific isotropic surface finishes that can increase service life]  http://www.slideshare.net/dryfinish/october-2013-f2-deburring-1

(6) Turbo-Abrasive Machining Demonstration Video:  https://www.youtube.com/watch?v=jYxqCxMIHNo

(7) SME Spokane, WA Factory Floor video, Centrifugal Finishing in the Precision Machine Shop: Demonstration)  https://www.youtube.com/watch?v=dUdKjaysTYM

Dave Davidson: Contributing Editor | dryfinish@gmail.com | 509.230.6821
https://about.me/dave.davidson |  https://dryfinish.wordpress.com 

CONTRIBUTING EDITOR BIOGRAPHY –  David A. Davidson, [dryfinish@gmail.com]

Mr. Davidson is a deburring/surface finishing specialist and consultant.  He has contributed technical articles to Metal Finishing and other technical and trade publications and is the author of the Mass Finishing section in the current Metal Finishing Guidebook and Directory.  He has also written and lectured extensively for the Society of Manufacturing Engineers, Society of Plastics Engineers, American Electroplaters and Surface Finishers Association and the Mass Finishing Job Shops Association.  Mr. Davidson’s specialty is finishing process and finishing product development.

More about Dave Davidson…

davidson-pic3 (2)I am a deburring and surface finishing specialist, consultant and advisor to SME’s [Society of Manufacturing Engineers] Technical Community Network. The focus of my activity is assisting manufacturers and machine shops with reducing their dependence on hand or manual deburring and finishing methods, and helping them to upgrade the edge and surface finish quality of their parts. I currently work from Colville, WA but I assist clients nation-wide. I can arrange for free sample processing and process development for your challenging deburring and finishing needs and can provide you with either contract finishing services or the in-house capability to produce improved hands-free finishes on precision parts. I can be contacted at 509.230.6821 or dryfinish@gmail.com. Let me know if I can be helpful.




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