No announcement yet.

Royal 5c lever collet closer-how to locate link pivot to be able to latch closer asm?

  • Filter
  • Time
  • Show
Clear All
new posts

  • Royal 5c lever collet closer-how to locate link pivot to be able to latch closer asm?

    I have only used a lever 5c collet closer on a Hardinge HLV-H. That was 5 yrs ago and probably my total time on the machine using the collet closer might total 2 or 3 hrs and I did not pay attention to the link geometry or what made the lever stay latched.

    I bought some loose Royal 5c lever collet closer parts - enough to make one complete asm and a few spare parts at an auction back in Dec. There were at least 3 or 4 lathes w/ Royal collet closers in the auction and this dummy did not think of operating the levers or of taking images of the closer installations. I am assuming (sometimes a dangerous thing) that the pivot point opposite the handle needs to go overcenter to latch the lever asm. So looking at the Royal diagram: I am presuming that pivot (at 7) has to travel overcenter with respect to the pivot at (2) and the pivot at the end of link (26). Correct? If not, how does the asm stay latched when the drawtube is under tension from a collet & stock at the far end? I have looked for installation instructions for other 5c lever asm and still it is not registering with me how the system will lock up:

    What am I missing?

    A couple of images of my parts: Click image for larger version

Name:	Royal 5c  plan view.jpg
Views:	262
Size:	1.27 MB
ID:	1940024 Click image for larger version

Name:	Royal 5c.jpg
Views:	240
Size:	1.30 MB
ID:	1940025

    In this image the pivot is (almost) overcenter: Click image for larger version

Name:	Royal pivot overcenter.jpg
Views:	241
Size:	1.25 MB
ID:	1940026
    Metro Detroit

  • #2
    It's been a while, but I think you are overthinking this. A lot of other collet closers are not the same as the Royal design, however the linked one seems pretty similar.

    The actual toggle happens on the little finger(s) inside of the aluminum collar bit that goes over the spindle tube. They rotate and impart a camming action on the drawtube that toggles into a locked position and imparts the pull force on the drawtube. Or maybe they go into a tooth?

    I don't think that there is any real specific orientation requirement for this link, as long as it's sturdy and doesn't hit the end of travel on either end (yoke on rod end). This part and the link that the handle is attached to only needs to impart axial force on the stuff within the aluminum collar.
    Last edited by psomero; 04-24-2021, 04:26 PM.


    • #3
      The adjustable linkage needs to be more toward parallel to the closer, not perpendicular.

      When used, the hand-lever pushes against the linkage to draw the tube outward, and then "trip over" to lock. Then, to unlock, the hand lever pulls against the linkage.

      Ideally, the linkage would be parallel to the closer, but in reality, "somewhere in that ballpark" is sufficient. Your second photo would work, though if it were me, I'd shorten the linkage a bit to get that angle a little closer.

      Doc's Machine. (Probably not what you expect.)


      • #4
        Nothing in the pictures will work very well. You need to shorten the linkage to get the mounting plate a lot closer to the spindle. Ideally, the link should be perpendicular to the lever handle when locked, but as noted above, close to that is good enough.
        Kansas City area


        • #5
          I have a PDF of the lever-style collet closer for a Clausing 5900-series lathe and believe that was made by Royal. PM me with an email address and I'll send you a copy.

          You could try calling Royal, but I think that they stopped making manual closers a few years ago and may no longer have or be interested in providing info on the subject.

          Mike Henry near Chicago


          • #6
            Thank you all for responding. A couple of hours after posting I found a paper copy of instructions from Royal (not sure where on the Web I found it (and when)). The instructions require an angle from 45 to 90 deg with respect to the end cover of the lathe. I scanned the instructions and was going to attach it but the scan file is too large.

            Are most lever closers like this - where the overcenter happens in the the "head" of the unit? Reason for asking, I also have a Hardinge 5c lever closer that I picked off of a 2nd op lathe (in a dumpster at my metal recycler, my buy price was $0.35/lb). I think it cost me about $6 but I had to remove it when it was in the mid 20s F back in Jan, my gloved fingers were hurting. The Hardinge needs a bit of work but the drawtube ID is about 1.28 in where as the Royal is about 1.10 inch ID. I only took one image of the link to lathe in the dumpster with the lever asm already pulled out about 1.5 inches and (guessing) that the link appears to be about 60 to 70 deg if the asm were fully inserted in the lathe spindle. I am guessing if I were to use that one the cast link that I am holding would be replaced by a very short link and pivot near the "head" of the asm - not sure if there would be enough travel with a very short link. Your thoughts - Royal vs Hardinge lever asm.

            Click image for larger version

Name:	hardinge 5c asm if used on Summit.jpg
Views:	201
Size:	1.31 MB
ID:	1940083 ‚Äč
            Metro Detroit


            • #7
              If you look at a Hardinge lathe, you will see that the spindle sticks out a long way from the headstock. Therefore the link has to be a lot longer to reach the attach point. It is still at a fairly right angle to the lever.

              Kansas City area


              • #8
                Given the geometry, I'd use the Royal, myself. They're both good quality and will do the job well, but the Royal will be easier to install.

                Doc's Machine. (Probably not what you expect.)