Constant pull Maschine question

Marcel92

New User
Hello I have the pros pro tomcat Mt-400, it is yes a constant pull machine, I have to wait after the beep signal until I disconnect since the numbers are dynamic. Say if I set for example 25kg, I release the clamp the number fluctuates. I make the clamp on and the number continues to fluctuate. Do I now wait until the desired 25kg are displayed and release Constant pull at the perfect moment or can I simply ignore the number fluctuations?
 

Irvin

Talk Tennis Guru
Once the machine beeps (meaning tension was reached,) first release the base clamp, then move the string clamp to the string that you just tensione, and lock the base clamp.
 
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esgee48

G.O.A.T.
Your string is stretching which is why the number fluctuates. Wait until it stabilizes or the unit beeps.

Then release the base, then release the clamp. Move to new location, clamp string then lock base.
 

tjanev

Rookie
I have the same machine. it'll do the initial pull to hit the desired number, then when you release the clamp, the string tension changes because now it's pulling on a longer part of the string ( not just at the clamp point to the mechanism ). therefore it's now going to be constantly adjusting till it gets to that 25kg point that you wanted. i'll usually watch the screen to see when the number starts balancing out to the desired outcome, then re clamp and release. Because strings have elasticity, and because you have friction points at each crossover grommet that may slightly shift the string forward from the constant tension, you could be spending a bit of time waiting for it to finally stop.

Let it beep, watch it adjust till it's getting pretty close to the desired number ( maybe another couple seconds ), and then re clamp and release.
 

Marcel92

New User
I have the same machine. it'll do the initial pull to hit the desired number, then when you release the clamp, the string tension changes because now it's pulling on a longer part of the string ( not just at the clamp point to the mechanism ). therefore it's now going to be constantly adjusting till it gets to that 25kg point that you wanted. i'll usually watch the screen to see when the number starts balancing out to the desired outcome, then re clamp and release. Because strings have elasticity, and because you have friction points at each crossover grommet that may slightly shift the string forward from the constant tension, you could be spending a bit of time waiting for it to finally stop.

Let it beep, watch it adjust till it's getting pretty close to the desired number ( maybe another couple seconds ), and then re clamp and release.
is it the same with all stringing machines? Coz no one talked about it in any tutorial videos i watched. If i clamp right next to the frame so it's "perfect" the number balancing pretty fast like 1sek max.
 
Just my 2 cents to this one:
The time that a pulling system keeps pulling depends strongly on the remaining elongation of a string.
With good strings with a good elastic to remaining elongation ratio the balancing should stop within 10 seconds.

Especially with stretchy monos the system keeps balancing “for ever” because the elastic elongation is small and remaining elongation is a lot.
You can find these figures in our list of tested strings.
 

malagabee

Rookie
Hello I have the pros pro tomcat Mt-400, it is yes a constant pull machine, I have to wait after the beep signal until I disconnect since the numbers are dynamic. Say if I set for example 25kg, I release the clamp the number fluctuates. I make the clamp on and the number continues to fluctuate. Do I now wait until the desired 25kg are displayed and release Constant pull at the perfect moment or can I simply ignore the number fluctuations?
Mine does this although I’ve just recently noticed how long it takes for readings to stabilize. We r taking 5 to 10s although it beeps within 1s after a pull. Using a digital scale with 2 decimal place precision during calibration my numbers can fluctuate within a .5 lb range. I strings mostly hyper G poly. For multies and gut. The effect will be greater. I handle this 3 ways. 1. Calibrate it to pull a little high to reduce waiting time b4 clamping off. 2. String at a higher tension. 3. Wait for 5 to 10s b4 it stabilizes.

I’ve read others posts of pro stringers telling people to clamp off right away just be consistent and just because they say so r ignoring each tension heads technical capabilities and the mileage on it. All in all a +-0.5 lb fluctuation or accuracy is pretty negligible considering other variations involved.
 
Mine does this although I’ve just recently noticed how long it takes for readings to stabilize. We r taking 5 to 10s although it beeps within 1s after a pull.

The time that it takes to stabilize depends not only on the amount of elongation of a string but also “how fast” a string is.
In a fast string the elongation is developed quick and in a slow string much slower.
The upper graph shows a fast string and the lower a slow string.

e5lockoutnylonsklj
 

fritzhimself

Professional
The time that it takes to stabilize depends not only on the amount of elongation of a string but also “how fast” a string is.
In a fast string the elongation is developed quick and in a slow string much slower.
The upper graph shows a fast string and the lower a slow string.

e5lockoutnylonsklj
Dear Fred,
your measurements are from the stone age with ancient syngut in diameters that are no longer available.
We are talking about polys here.
Show us a new measurement with copolys of the last generation.
 
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Dear Fred,
your measurements are from the stone age with ancient syngut in diameters that are no longer available.
We are talking about polys here.
Show us a new measurement with copolys of the last generation.
Hi Fritz,

The graphs are only meant to show the difference between a fast string and a slow string.
Because that explains the difference in waiting time until the tensioner stabilizes.

Besides I hope that you are not saying that the new polies are better than those strings of 20 years ago.
We stopped doing the tests in 2016 because the new strings were only more of the same with nothing new.
 

fritzhimself

Professional
I mean, you can't compare apples and oranges.
The elongation behavior of a modern Co-Poly is different from that of a SynGut.
That's why I think this graphic is outdated.
I also think that the statement that a fast stringer is a soft stringer (when using a co-poly) is outdated or wrong - many people (not only me) have proven this many times.
 
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I mean, you can't compare apples and oranges.
The elongation behavior of a modern Co-Poly is different from that of a SynGut.
That's why I think this graphic is outdated.
I also think that the statement that a fast stringer is a soft stringer (when using a co-poly) is outdated or wrong - many people (not only me) have proven this many times.
As often we totally disagree.
One of the best monos ever made was the Polystar of Trevira and the Polylon of Goosen, these were made in the 80’s.

I say nothing about a fast stringer I am talking about the speed of development of the elongation in the string,

Hereby the graph of 2 different monos.
6flockoutmonos1klj
 

fritzhimself

Professional
Really :unsure:- these are some of the first polyester strings that have nothing to do with today's poly strings in terms of tension stability - it's like 4 cylinders against a V8 engine.
The Polystar already put its tension stability in the cellar during stringing and the Polylon had to be cut out after playing in.
 
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Interesting video.
Question is: What time did he take for the moment that the tension was reached. At the moment that the tensioner reached the tension the first time or after all the elongation was removed from the string?

Imo it can not be the last option because even fast strings need more time than 3 seconds.
 
Hereby some additional info about the constant pull / string subject:

This table shows the classification of strings.
Look at the number of strings (mainly monos) in the class Sxc. The amount of remaining elongation is so high that the string will loose tension too quickly. The lower the el/tot ratio (grey column) the worse the tension stability.
http://www.stringway-nl.com/pdf/EN/Snarentest2015-1optotrek-ENG.pdf

This graph shows the progressive elongation of the Polystar. This gave the string a special playability, with good feeling on low power hits and longer ball contact (control) on hard hits. Best stringing tension was 45 to 50 lbs.
pm5aZ1x0j

To compare the graph of a good multifilament syntectic string.
p8B5qC1tj

This picture shows the meaning of the figures
pmkqHQZjj
 

malagabee

Rookie
Since OP and I have the same PP Tomcat MT-400. I’m here to say I was able to get the tension display to settle out to reference tension quicker by playing around with a hidden menu function. If interested how to get into the hidden menu just PM me.

However no matter what tension head u have the only way to know how fast the tension settles is not by looking at the tension heads display but rather pulling a piece of string attached to a digital scale with 2 decimal precision. If u have Kevlar string attached u won’t see the fluctuation as it won’t stretch so use a string that you’d normally string with.

After changing a hidden menu option I was able to make the tension head less sensitive to the string’s counter pull on it. Meaning the MT-400 displayed tension stabilized quickly within 3s and won’t fluctuate. But the strings tension still took time to settle and jump around as measured and seen on the digital scale for 10 to 15s
 
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