…The Premier Timp Clutch Mechanism

Every timpanist should know…
…How the Premier Timpani Clutch Mechanism Works.

The Premier clutch mechanism has three elements that work in conjunction with each other: The pedal, the fork pressing linkage, and the clutch block. It must be noted that they are not operated in isolation, they are part of the whole pedal assembly which in turn is part of the whole instrument. However the system can be simplified to the above three elements to empower a timpanist to be able to overcome most problems.

The pedal rocks back and forth around a fulcrum point, just like a see saw. Immediately below the fulcrum point is the barrel nut which holds the connecting rod to the fork pressing.
With the heel down the pedal moves the barrel nut forward.
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It can be seen that the pedal is pushing the connecting rod forward, thus pushing the top of the fork pressing forward. The fork pressing also rotates around a fulcrum point, so it can be seen that as the top is pushed forward the fork prongs are pushed down.
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This downward movement of the fork prongs enables the sleeves in the clutch mechanism to be pushed downward by their respective springs (not in the drawing for clarity). The bottom sleeve has a spring that is visible which pushes against the bottom of the clutch block. The spring around the top sleeve pushes against the chrome cap that is fitted on the top of the clutch block (not in the drawing for clarity).
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The top sleeve has an angled face that pushes the ball bearings down and outwards away from the grip rod. However the inside of the clutch block is conical. As the sleeve pushes the ball bearings down, there is less and less room for them to go out, so they are in actuality forced down between the clutch block and grip rod. This wedging of the ball bearings is what holds the pedal arm in the desired position.
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To release the clutch, the toe is pushed down on the foot plate, which rotates the barrel nut backwards (toward the player).
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This movement pulls the connecting rod and the top of the fork pressing. The fork pressing rotates lifting the prongs upwards.
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The fork prongs push the clutch sleeves upwards, compressing their springs.
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As the bottom sleeve lifts the balls, they become unwedged as they move up the conical shape of the clutch block. The angled face of the top sleeve can now push the ball bearings outwards away from the grip rod.
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Because the ball bearing are being pushed away from the grip rod it is no longer held, therefore the tension on the head can be released lowering the pitch. Once the pitch is achieved, the pedal is rocked backwards by pushing the heel down. This action, as we now know, enables the spring on the top sleeve to wedge the ball bearings again, with the spring on the bottom sleeve pushing the sleeve down out of the way. Below is a photo of the complete assembly.
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Now the system is understood, we can move onto the adjustment which is simplicity itself. The connecting rod between the fork pressing and the pedal is threaded so that its length can be adjusted. Making it shorter will therefore push on the balls and release a stuck pedal, making it longer will enable the balls to go down further thus preventing a slipping clutch.

There is a supplementary post to this one that explains how to release a jammed pedal which includes a video of me demonstrating how to do it.

7 comments on “…The Premier Timp Clutch Mechanism

  1. David Campion

    Hi Paul
    I have another question pending on another post but thought I’d ask here as this is another timpani issue I need to deal with. The clutch mechanism on my 40 year old Premier timps feels “tired”. I need to ‘help’ the pedal to return from it’s position at the top of the range by pulling up underneath the heel of the pedal. Are the internal springs worn out and are these parts replaceable (slightly more problematic as I live in Canada)?
    Thanks
    Dave

    Reply
    • pauljefferies

      Hi Dave,

      There is no way you should be needing to help the pedal back up to get the pitch back down. The next development with your timps will be that the pedal has jammed solid. This is the reason why I wrote this article. Follow the instructions and watch the video, it should have all you need to know. However if you do have any problems or questions, come back to me.
      Paul

      Reply
  2. Keith B Cosby

    The lower Spring on the clutch mechanism has become distorted and when pedal is pressed fine but will not return do you supply spares if so what is the cost

    Reply
    • pauljefferies

      Hi Keith

      I keep lots of spare parts in stock, obviously I do so for my use, but I do sell them to individuals. However I think that there is more wrong than the lower spring being distorted. That spring is very weak and is almost only there to prevent to prevent rattles. Your problem could be down to many things including lubrication, sleeve wear, clutch wear or grip rod wear, ordered from best to worst case scenario and therefore increasing in price. Email me directly to get prices, or telephone to discuss further because I don’t want to sell you parts and then spend hours trying to sort out why they don’t work via email when I advise that in reality it sounds like you need to service your drums.

      Paul

      Reply
  3. Guy

    Hello, I service and repair a number of different types of timpani including Premier – can you please help me with information about the thread size/type of screws which hold the bracket in place on the inside of the fulcrum? There are four, two on each side, one above the other on both sides. Also, I think the type of screw has changed over the years? Is there now one used which does not have a tapered thread?
    Thanks,
    Guy.

    Reply
    • pauljefferies

      Hi Guy

      Your question raises several issues:

      The very reason that I have a website is to demonstrate to potential new customers that I know this stuff, whereas my competitors don’t. My website is my shop front, a window into my workshop enticing people in and to spend their money in exchange for my knowledge, skill and expertise. Therefore my the content of my site is a demonstration of my proficiency, attitude and approach towards my job. Whilst I accept that people use my site as a reference tool and even as inspiration to undertake repairs themselves, I continually show that most people should not be working on these instruments because they do not understand what they are doing.

      For instance, your screws – If I didn’t have the information then I would be able to find out either by measuring the screws in question or speaking directly to Premier. In extremis I could adapt the holes to accept a known screw size.

      Paul

      Reply

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