Racquet strains while stringing crosses

Discussion in 'Stringing Techniques / Stringing Machines' started by Muppet, Sep 18, 2013.

  1. Muppet

    Muppet Hall of Fame

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    My stringer is an Alpha Pioneer DC+ dropweight with a 6 point mount and fixed clamps. The racquets are the Dunlop MuscleWeave 200G 95 and the Dunlop Biomimetic 200. Both have oval shaped heads. I've noticed that while I'm tensioning the crosses in the bottom half of the hoop, the lower side mounts nearest the bridge become loose. And the frame makes a straining sound which could be graphite fibers breaking.

    To avoid this, I was wondering if I should mount the racquet a little lower, to fill up the lower side contact points better. I'm thinking of only a 1/16" fudge from center. If not, what would be a better approach?

    Thanks in advance.
     
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  2. Irvin

    Irvin G.O.A.T.

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    Sounds like you are not mounting the racket right. For the racket to get narrower it has to get longer and vice-a-versa.

    EDIT:Maybe check to make sure the racket is the correct length after mounting and all supports and snug but not tight.
     
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  3. struggle

    struggle Hall of Fame

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    how loose are we talking (the side mounts)?

    perhaps you just need to snug everything up abit more.
    don't overkill it, but with fingers, tighten until snug. i tighten back and forth, very little at a time between 6/12 and side mounts....until neither want to move without excessive pressure.

    i often string the MG Radical MP (flexy frame) with out problems doing as i described.
     
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  4. tball

    tball Semi-Pro

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    I wonder if your mains are too loose. ( Clamps were slipping when you were stringing mains? ) If crosses are at much higher tension than the mains, this will squish the racquet sideways, making it longer and narrower. There is nothing in the mounts against making the racquet longer. Mounts only prevent the racquet from being squished from top to throat when you are stringing mains, but not in the other direction.

    String the crosses lower, and the elongation should not occur.
     
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  5. Muppet

    Muppet Hall of Fame

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    I think you have it there. I've been hybriding poly/multi at a 5 lb. tension difference. I didn't think the multi cross would make that much of a difference. I guess I'll back down to 48/52. I already mount my frames just a little snug. What other precautions can I take to keep my racquets from straining? For another point of reference, my racquets don't strain under pressure when I use a one piece ATW pattern.
     
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  6. Irvin

    Irvin G.O.A.T.

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    Why you would want to put your multi in the crosses is beyond me, but that is not your problem. And going from a 5 pound difference to a 4 pound difference won't fix anything either.
     
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  7. Muppet

    Muppet Hall of Fame

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    I can see now why some people prefer a two-point mount.

    Irvin, I'm not over-tightening the mounts. And I don't want to go down significantly on the cross tension. What else can be done to avoid damaging my racquets? Should I opt for a stiffer cross at a lower tension? Synthetic gut with a 2 pound difference? Or a stiffer multi at a 3 pound difference? The Hexy Fiber plays so well. :confused:
     
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  8. Ken Sachar

    Ken Sachar Rookie

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    Muppet

    Isn't this stringer notorious for tower creep? Maybe that is why the racquet is so distorted. Chech other threads about tower creep.

    Ken
     
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  9. Irvin

    Irvin G.O.A.T.

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    Tower creep could be your issue. Mount you racket and check the overall length. Then string your mains and check the overall length. There will more than likely a small difference but if it if more than about 0.25" tower creep is your issue.
     
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  10. Muppet

    Muppet Hall of Fame

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    Is the straining that I'm hearing the towers moving, rather than my racquets? That would be good news for the racquets. Come to think of it, I do seem to get an inordinate amount of power from the lower stringbed. This is evidence that the towers are moving and delivering lower tension as the string job goes on. I'll contact Alpha to see if they can send me instructions on fixing the problem.
     
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  11. Muppet

    Muppet Hall of Fame

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    Well, Greg at Alpha recommended that I add some larger washers to the ones already on the tower tightening knobs and, after doing so, it feels like a very secure fit. I'll see if I get that loosness in the mount and the straining in the racquets next time I string them. It looks good so far.

    edit: Should I put the more rounded side of the washer toward the knob or the track?
     
    Last edited: Sep 19, 2013
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  12. Muppet

    Muppet Hall of Fame

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    The problem of the tower creep is fixed, but now the clutch spring is shot. The problem moves around. Does anyone know if replacing the spring is a very difficult job? I'm not very handy and I'll have to go buy the two or three tools that I'll need, in addition to ordering the spring from Alpha.
     
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  13. Imago

    Imago Semi-Pro

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    Sorry to hear that. I still think this clutch should be used only to level the gripper.
     
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  14. Imago

    Imago Semi-Pro

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    All you will need is a hex driver No 6 and a wrench No 12.
     
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  15. tinyman

    tinyman Rookie

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    Very easy to do. As mentioned above - I needed a pair of tweezers to pull out the end of the spring, and I applied a bit of motor oil when I put it back together.
     
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  16. SwankPeRFection

    SwankPeRFection Hall of Fame

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    Put them on the track, then the factory washer on top of that and then the knob. It also may require tightening with a plumbers wrench, but just every so slightly more than by hand in case you can't get enough torque by hand. Wrap the knobs with something so you don't damage them.
     
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  17. Ramon

    Ramon Hall of Fame

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    I have the same machine and used to have the same problem with creep. I tried bigger washers, and I tried a piece of leather under the towers, but they didn't work. Here's how I fixed it. I put an adjustable rod in between the towers.

    [​IMG]

    I modified the idea recently by using a 3/4" wide 1/8" thick flat piece of zinc-coated steel. The flat piece doesn't get in the way of the clamps. I don't have a picture of that one right now, but you get the idea.
     
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  18. oest10

    oest10 Semi-Pro

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    I would like to see your mod up close! Could you post some (bigger) pictures?
     
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  19. Muppet

    Muppet Hall of Fame

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    I successfully was able to replace the damn clutch spring. It was a lot harder to do than I expected. I had to get $48 worth of tools and re-assembling the new spring into the hub assembly required some awkward guesswork. Next thing, I started to place the bearings in the wrong place and in the wrong order. It didn't look right and I was able to straighten it out before tightening everything up. Greg and Mark gave me good instructions which helped a lot. I'll try stringing a racquet tommorow. Maybe I'll get a correct tension for once.
     
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  20. Ramon

    Ramon Hall of Fame

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    Sorry, I had a hard enough time just getting this picture posted. It's really not that complicated. With the setup in the picture I have to insert the rod after the middle mains are strung (the towers don't creep until most of the main are strung).

    The one I'm using now is a flat piece of steel about 1/8" thick and 13" long and 0.75" wide. You just slide it between the towers, and you can keep it there. The towers will not budge and the swivel clamps will still swivel.
     
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