Adjusting Neos 1500 Clamps Properly

[alhs77st]

I recently purchased a Neos 1500 (I've only strung three frames on it to date). Today, I was playing with the clamps to see how tight I needed to make them for string not to slip while tensioning. My method was as follows:

1. I locked the turntable and clamp base. (The turntable and clamp were oriented as if I were pulling tension on a cross string.)
2. Put Luxilon Alu Power Soft (16) in the clamp (and closed the clamp).
3. Put a paperclip on the string between the clamp and tension head.
4. Pulled tension and observed if paperclip moved.

What I found was that in order for the string not to slip (i.e., for the paperclip not to move) I had to adjust the clamp so that it left an impression on the string (if it were any looser, the clamp wouldn't leave an impression, but the string would slip).

First, is this a valid way to determine how tight you need to adjust your clamps? (I know you probably wouldn't do this every time, but I'm trying to develop the proper feel.)

Assuming it is, are these sorts of impressions normal? Is it because of the string I'm using (yes, it's soft, but it's also a poly).

Thanks, in advance, for your help.

P.S. Yesterday, I cleaned my clamps using a toothbrush and alcohol, so dirty clamps is not the issue.

 

[Irvin]

Put a racket on the stringer pull tension on a string and clamp. I think you will find you need less clamping pressure to hold the string. What you have done with your present test is make a good case for using a starting clamp to start mains.

 

[alhs77st]

Thanks, Irvin -- I appreciate the response! I actually stole that idea from this (yes, it's for badminton, but I assumed that didn't matter):

Anyway, assuming I first did the following:

1. Started the mains using the Yusuki method;
2. Pulled tension on the main that isn't clamped and clamped that main.

Where do I test for slippage -- at the clamp that I used to hold the first main (i.e., the one I'm also holding with a starting clamp) or the newly clamped main? If it's the latter, on what side of the clamp would I put the paperclip/mark the string?

Also, why does my initial test not work? Is it the friction of the string through the grommet that reduces the pressure needed in the clamps, or something else?

Thanks!

 

[eelhc]

A bit off topic but since we are talking about adjusting for the strings, one of the modifications I made to my Neos 1500 is a longer screw that sets the gripper spacing. The one that ships with the machine did not allow for wide enough spacing to prevent ghosting with gut or marking up poly.

 

[Irvin]

Thanks, Irvin -- I appreciate the response! I actually stole that idea from this (yes, it's for badminton, but I assumed that didn't matter):

Anyway, assuming I first did the following:

1. Started the mains using the Yusuki method;
2. Pulled tension on the main that isn't clamped and clamped that main.

Where do I test for slippage -- at the clamp that I used to hold the first main (i.e., the one I'm also holding with a starting clamp) or the newly clamped main? If it's the latter, on what side of the clamp would I put the paperclip/mark the string?

Also, why does my initial test not work? Is it the friction of the string through the grommet that reduces the pressure needed in the clamps, or something else?

Thanks!

I believe your test will work it just ends up with a tighter clamp that you need. You test should be on a string you're tensioning. Say you use the Yusuki method and have your clamp and starting clamp on 1RM. When you tension 1LM you do the test. After You clamp 1LM and release tension there will probably be some drawback resulting on less tension on 1LM. Where in you intiial test you had full reference tension on the string being pull.

 

[alhs77st]

On further reflection, I think the answer to my second question is "something else" -- specifically, string tension. In my method (i.e., the one in the video), there was initially no tension in the string when I clamped it; this forced the clamp to do all the work (which is why it had to be so tight). Is this correct?

 

[alhs77st]

Hi Irvin -- looks like we posted within seconds of each other (so I didn't get a chance to read your answer before I typed up mine). Sounds like we're on the same page, though. However, just to be clear...

When you pull, say, 50 lbs. of tension on a string, what does the force diagram for an arbitrary point on the string look like. Is it 25 lbs. of force pointing toward the tensioner and 25 lbs. of force pointing in the opposite direction, or is it 50 lbs. in both directions? (Sorry, my physics 101 is rusty.) If it's the former, then everything makes sense: in this case, the clamp only has to supply 25 lbs. of force to the string to maintain the 50 lbs. of tension. In my test, on the other hand, it had to supply the full 50 lbs. all by itself.

If this is, indeed, the case, is there any way I could have damaged the clamp by applying that much force directly? It certainly doesn't look like I did, but I tend to worry about these things.

 

[alhs77st]

A bit off topic but since we are talking about adjusting for the strings, one of the modifications I made to my Neos 1500 is a longer screw that sets the gripper spacing. The one that ships with the machine did not allow for wide enough spacing to prevent ghosting with gut or marking up poly.

I've noticed that the gripper marks up the string a bit, too. Looking on the forums, I found a couple of threads addressing this. One (http://tt.tennis-warehouse.com/index.php?threads/damaging-string-with-prince-neos-1500.342553) basically concluded that these marks didn't impair the string's life (and, possibly, that Prince designed the gripper that way on purpose to prevent slippage). Someone on another thread (http://tt.tennis-warehouse.com/index.php?threads/prince-neos-string-crimping-problem-beginner.419430) felt the issue could be solved just by loosening the screw that comes with the machine. But it sounds like, for you, that wasn't sufficient. Is that correct?

Also, I haven't found that those marks have impaired the lifespan of my strings (I still get about five hours out of a set of strings before they break or I need to cut them out because playability has dropped too much). Have you found the marks to be a problem, though? Did you ever contact Prince about this?

 

[Irvin]

On further reflection, I think the answer to my second question is "something else" -- specifically, string tension. In my method (i.e., the one in the video), there was initially no tension in the string when I clamped it; this forced the clamp to do all the work (which is why it had to be so tight). Is this correct?

I don't think so. I think you should tension a string and clamp it like it is done when you string a racket.

I've noticed that the gripper marks up the string a bit, too. Looking on the forums, I found a couple of threads addressing this. One (http://tt.tennis-warehouse.com/index.php?threads/damaging-string-with-prince-neos-1500.342553) basically concluded that these marks didn't impair the string's life (and, possibly, that Prince designed the gripper that way on purpose to prevent slippage). Someone on another thread (http://tt.tennis-warehouse.com/index.php?threads/prince-neos-string-crimping-problem-beginner.419430) felt the issue could be solved just by loosening the screw that comes with the machine. But it sounds like, for you, that wasn't sufficient. Is that correct?

Also, I haven't found that those marks have impaired the lifespan of my strings (I still get about five hours out of a set of strings before they break or I need to cut them out because playability has dropped too much). Have you found the marks to be a problem, though? Did you ever contact Prince about this?

Assuming you have no Diablo the gripper may leave some ghosting on the string.

EDIT: Not sure about the 1500 stringer so I'm wondering if the string from the clamp to the tension gripper is level or not. If the string were going through a frame it would be level.

 

[1HBHfanatic]

it all comes down to feel
youll need to feel for yourself how much is too much
this is because of all the differences in string type, gauges and material used, plus the lubricating material of each string
multis will suffer most of the ghosting since they flaten out easier and also seem to have very slippery material on them
some synthetics also require extra force to keep them put
i have a good feel for the flying clamps ive been using with my home machine
but recenttly been asked to use a 1500, fixed clamp machine, i am struglling trying to make sure i have enough pinch to work
ive been ghosting the strings provably a bit too much, but thats until i get to know the clamps and whats needed
one other point though about ghosting, ive read this and experienced this, when you pull tension on a string, the ghosting seems to discepate or be less notisable as the string goes from flat to round again (if you dont exed the "squash" too much).

 

[eelhc]

I don't think so. I think you should tension a string and clamp it like it is done when you string a racket.

Assuming you have no Diablo the gripper may leave some ghosting on the string.

EDIT: Not sure about the 1500 stringer so I'm wondering if the string from the clamp to the tension gripper is level or not. If the string were going through a frame it would be level.

The factory stop screw that limits gripper travel is a bit short. Tightened all the way (least travel for the grippers), the gripper can still ghost/leave marks on some strings. It's an easy part to upgrade. I actually have a REAL hardware store nearby which specializes in fasteners so it was an easy upgrade.... Just brought the screw in and asked for a longer one... They measured the length, thread size and gave me a longer stainless steel cap screw.

 

[Irvin]

The factory stop screw that limits gripper travel is a bit short. Tightened all the way (least travel for the grippers), the gripper can still ghost/leave marks on some strings. It's an easy part to upgrade. I actually have a REAL hardware store nearby which specializes in fasteners so it was an easy upgrade.... Just brought the screw in and asked for a longer one... They measured the length, thread size and gave me a longer stainless steel cap screw.

What are you talking about? I realize how the stop screw works. If you back the screw all the way out you put the most pressure on the string, and have the greater chance of ghosting. If you run the screw all the way in you have the greatest chance of the string slipping causing marring damage.

If you adjust the clamps on any stringer with 360 rotation and the string goes from the clamp directly to the tension gripper (unless you have a Diablo or roller guide) the string is not under tension when you grip the string. Because the string is not under tension it is about 0.04 mm less in diameter so you will crush the string more than if it were under tension. Then when you tension the string the string starts stretching inside the clamp and your mark (or paper clip) moves farther from the clamp. Also the string going through the clamp and tension gripper is not parallel to the string going from clamp to the tension gripper.

If you put the string through a frame and tension a string the string is straight from one grommet to the other so when the string is clamped the string is stretched to the smaller diameter and the string goes straight through the clamp and remains parallel to the string. The tension gripper is angled upward so for the most part it is parallel to the string angling down from the racket also providing for less chance of movement

 

[eelhc]

What are you talking about? I realize how the stop screw works. If you back the screw all the way out you put the most pressure on the string, and have the greater chance of ghosting. If you run the screw all the way in you have the greatest chance of the string slipping causing marring damage.

Even when the factory screw was in all the way there was too much pressure on 16G strings. Replacing the factory screw with a longer one allows the the gripper to stop squeezing earlier.