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  1. I have been looking for retention knobs that are of the quality you need in an aircraft parts manufacturing facility and your High Torque Retention Knobs meet my requirements. We found that the machines are much quieter when roughing titanium and stainless steel. When roughing titanium and stainless steel with your knobs the power meter showed a significant reduction in power consumption and tool life was improved. Also our Fadal machines used to make a loud noise when changing tools and your knobs solved that problem. The retention knobs also eliminated the fretting of the toolholder shank. We have replaced all the retention knobs in the plant with J&M High Torque Retention Knobs and plan on using them on all new toolholders plant wide.

    Daniel Nietzold
    L.H. Thomson Co.

  2. J&M’s Hi-torque knobs really do work. Like most people I was skeptical (that) the change from a standard retention knob to J&M’s new Hi-torque style would have much, if any improvement on our tool holding. And when we received the test knob in plant, it was used on our toughest machining application, high speed surfacing on hardened YXR33 material at 50 Rc. The initial visual look at the part after the cycle, (showed that) nothing really seemed any different. We did not see the real difference the knob made until our operator began to hand polish the part to the required surface finish. This process was taking 28 minutes per part, and after switching to the high torque knob it only took the operator 2 minutes to polish the part into the correct surface finish (8 micro). That was an immediate savings of 26 minutes per part. This reason alone was enough to switch over all of our milling centers to Hi-torque retention knobs.
    Best Regards,

    Justin London
    Briney Tooling Systems

  3. With the advent of high performance machines it is even more critical that the entire machining system be assembled with a higher level of precision than common today with conventional practices. Changing out of worn tool holders and the use of high quality, better designed retention knobs is essential to step up the level of precision needed to get the desired level of performance from the latest machine tools.

    The J&M High-Torque Retention knob design provides added precision by reducing taper distortion in addition to just overall better precision due to its high level of manufacturing tolerance. As a result one can expect improved repeatability in the assembly of tool and spindle compared to conventional retention knobs. This can only serve to improve vibration behavior and result in better predictability and control of vibrations.

    Side Note from J&M Machine
    The following is a short bio on Dr. Delio:
    Dr. Tom Delio is considered one of the nation’s leading authorities on high speed machining and machine tool dynamics. Dr. Delio co-founded, along with renowned machine tool pioneer Dr. Jiri Tlusty, Manufacturing Laboratories Inc. (MLI) and continues to serve as its President. Dr. Delio’s has worked at MLI for the past 13 years performing development work in high-performance machining and commercializing MLI’s resulting products. This work includes high-speed spindle development, design of high-speed and high-precision machine tools, adaptive controls for high-speed machining and dynamics characterization methods of machine tools. Most recently Dr. Delio has led work on MLI’s new product line for measurement and characterization of machine tools for the production shop environment. He has authored several papers in the area of spindle speed control and holds a patent that is utilized in several of MLI’s products. Dr. Delio was selected as one of the six original partners of National Center for Defense Manufacturing and Machining; he is a Registered Professional Engineer; Certified Manufacturing Technologist and was the Recipient of the 2003 Pinckney Award (American Helicopter Society). He holds a BS, MBA and PhD from the University of Florida and a MS from Pennsylvania State University.

  4. On behalf of Hansen Engineering I would like to thank all the people at J&M Machine for bringing us a great new design retention knob (JM31275HT) for our 50 taper v flange tool holders. These knobs were 1st introduced to us at the 2010 Westec show in Los Angeles. They demonstrated the benefits of changing these knobs (and) we knew that we had to try them on a few troubled jobs. We bought 25 pcs. the 1st time and installed them following the torque specs and right away we noticed a 5% spindle load decrease using a 3.0” hi feed insert mill running titanium. We also installed them on a aluminum forging job we are running, that has always had chatter problems. Among the tools that we tested for this job include 1-1/4” knuckle rougher and 2.0 “ finisher. The results were great, the chatter was eliminated and it was the best finish we have ever seen on this parts. Since then we have bought 50 more pcs. and noticed improvements all around the table. These retention knobs have shown us lower spindle loads which is better for the machine; in turn we can increase speeds and feeds that gives us better cycle times. With improved finishes the quality of our parts are better and gives us a piece of mind when running these jobs. I would like to put a word out to the people who are not quite convinced yet, they are worth the small investment. You may not want to jump in with both feet but just try them on a job or two and I am sure that you will notice improvements. In this competitive world we live in today, we can use a product like these retention knobs that is something that we can just screw in our tools to give us a upper hand on our competitors’.

    Curtis Sampson
    Shop Lead-Man
    Hansen Engineering Co.
    24050 Frampton Ave.
    Harbor City, CA 90710

  5. The retention knob samples you sent to my customer had a positive test even though the holder already had a fair amount of distortion (it was very well worn). I will be selling all of your retention knobs in the future.

    Keep up the good work!

    Eddie Connelly
    Linco Tooling

  6. In the parking lot going into a sales call, I could hear a mill screaming in the plant. The piece was 304SS pipe about 1′ long with a 2.5″ dia. welded to a flange. They were milling the face of the flange after it had been welded on the end of the pipe; it was very noisy, acting as a tuning fork. I asked the operator if he would like to try a new HT knob for his machine; it might quiet it down. He said everyone in the shop would be very happy if anything could help.

    We changed the knob to a J&M’s new HT knob. You could hear very little noise from the milling operation after changing the knob to the new High Torque knob.

    Brian Dills
    JIT Industries

  7. I never imagined I would get excited by a retention knob. A pull stud. A commodity item, nothing sexy about it. Never though I’d have a reason, other than price, to want to sell one brand over another! Thank you for enlightening me!

    I’m up much later than I should be, reading over the information you sent. I have sung your praises to Remco’s owners, and they are very excited to have access to such a simple but extremely innovative product.

    Thanks again.

  8. After reading about your new retention knobs it made sense to try them and we are very pleased. We will be using your knobs as we replace the old and worn ones.

  9. I thought the result (using the JM11122HT) was excellent. I noticed that my 2 inch, 3 flute face running 8000 rpms in aluminum ran quieter. Also, my 3 flute, 1/2 inch aluminum end mills had better finishes when taking heavier cuts. I also found that on a job that I regularly run in 1018 steel, I was able to take heavier cuts and got longer tool life.

  10. After reading about your knob problem findings in a trade magazine I checked my holders and found the bulging you described. I ordered two of your knobs and eliminated the problem. I rubbed the holder on my surface plate and could detect the bulge on new holders but after installing your knobs the rubbing left a straight line. My small VMC cuts quieter and acts like a bigger machine.
    Randy Bolt
    River Rock Machine and Tool

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