Six-Point Suspension Vs. Six-Point Internal

The plastic piece can be rip off very easily. As rubber damper I use the black rubber that you can see on the picture. I cut it smaller so that it has the size of the plastic piece. Then use clue to fix it. That's all.

 

thanks.. where did you buy your rubber damper?

 

hmm.. many differents points of view.. some says load spreader is not needed as long as you mount your racquet properly and some says it really help to spread the stress around the 12 o'clock.. who to believe is it a design flaw or stringer's fault.. thanks Pete LSD for that link

 

the rubber was also deliver when i bought the machine to replace the old once if they were worn out.

 

In physical view a load spreader has the bigger benifit of both system because as you mention it "really helps to spread the stress around the 12 o'clock.." in comparison to that one that's eagnas use where the stress ist concentrated to one point.

 

Hi guys,

No comments on this particular machine out of fellowship to our former agent.

BUT:
I would like to make some remarks about such a support system especially for a badminton racquet which is much more vulnerable than a tennis racquet.

We have a stringing knowledge quiz and one of the questions is:
* Indirect (6 point outside) racquet supports allow less distortion, resulting in less stress in the racquet material. o True o False

The answer is False, and the explanation is simple:
* A minimum distortion does not mean a minimum stress in the racquet.
* A racquet does not get damaged because of too much distortion but because of too much stress in the racquet material (stress = force per square mm kg/mm^2)

The maximum stress in the racquet occurs at the moment that all main strings are tensioned.
The forces of all the main strings want to make the racquet shorter the support has to prevent that.
When the racquet gets shorter it also gets wider.

There are 2 ways to protect the racquet:

1) A DIRECT support that prevents the racquet from getting shorter with inside supports that work in the opposite direction of the forces of the main strings.
2) An INDIRECT support with supports against the outside that prevent the racquet from getting wider.

The stress in the racquet is considerably lower on a (inside) direct support than in a (outside) indirect support, the picture with the beam in the wall explains that:



The weight is too high so the beam needs help of a support.
Figure 1B shows an indirect support in the position where displacement of the beam is maximum.
Figure 1C shows a direct support the beam is supported close to the position of the weight.

The bad thing of the indirect support (1B) is that the support in A introduces a high stress in the beam between point A and C, while the force of the support has to be transferred to the position where the weight hangs.
There is no stress at all between A and C in 1A and 1C.

This means for an indirect (6p-outside) racquet support that the outside supports introduce stress in the racquet between the position of the supports and the positions of the main strings.

The “smoke curtain” in this matter is that stringers think that the best racquet support does not allow any distortion, while the stress in the racquet is actually higher than in a support that allows more distortion.

Our computer calculations show that the stress in the racquet ) is already lower on a simple 4 point direct support (like on the Prince Neos) than on a complicated Indirect 6 point support.

If readers want more information about this item I will be happy to show it.

Any readers of this who would like to test their stringing knowledge and receive the quiz just let me know and I will send it to you.

Stringtechno

 

Difference Between Stress And Deformation

Hi Pete,

The question is: What should be the major quality of a racquet support?
In my opinion it is much more important to protect the racquet against cracks then to offer the easiest way to put the racquet on the machine.

Of course I agree that ease of use is important but not on the cost of the danger to damage racquets on your machine.

And certainly with badminton racquets which are strung at the limit of their mechanical possibilities nowadays it seems important to keep the stress in the racquet as low as possible.

The difficult difference between deformation and stress is that you can not “see” stress. When the stress in a racquet has been too high during stringing it will probably come out when it cracks during play.

One advise for users of 6-point (indirect) supports:
The stress in the racquet goes up when the supports are placed closer to the 3 and 9 o’clock position.
Place the outside supports no further away from the middle then 2 and 10 o’clock.

An advise for people who want to buy a 6-point support machine:
Buy a machine on which it is possible to place the supports in different positions, so the supports can be placed at 2 and 10 o’clock for every size of racquet.

Stringtechno

 

Damage of racquets at 12 o'clock.

Based on the link in the private message from Cooler http://www.badmintoncentral.com/foru...noon#post30732I would like to add some information about racquet supports.

This discussion deals with the fact that many racquets are damaged badly in the 12 o’clock position on 6-point indirect supports.

The reason for this damage, which reveal often during play, is that the stress in the racquet is huge in the 12 o’clock position for 2 reasons on indirect supports:
1) The total force of all main strings has to be transferred to the support system through the central 12 and 6 o’clock supports.
The narrower the support the higher the pressure against the inside of the frame.

2) The forces of the main strings want to bend the frame around the central support, which results in a very high bending stress at the 12 o’clock position
The figure shows what happens a little exaggerated.


Advices:
* If you choose a machine with an indirect support choose one with a very wide support at 12 and 6 o’clock.
* Choose a machine on which the supports can be placed in different positions. The graph below shows that the stress in the racquet gets higher when the supports are placed closer to 3 and 9 o’clock. The graph shows the stress in an oversize tennis racquet for different support systems.


It is dangerous to use machines with fixed outside supports for badminton which are designed for tennis

The worst thing to use is a bar that prevents distortion on 3 and 9 o’clock, the stress around 2 o’clock will be huge.
(These bars were “invented” for tennis around 1985 and the racquets broke on the machine, so the thing disappeared quicker than it came).

The best solution is to take a machine with inside direct supports which are very wide, so that the pressure is low and the forces of the main strings are “absorbed” directly by the supports without working on the frame.

 

a well-made loadspreader will solve a lot of those problems, I string 20-29 lbs on a lot of rackets (29 on ym own) without any cracks at 12 o clock, because I use a load-spreader.
(and yes, I have a 6 point machine, and yes, the supports are at 2 and 10 o clock)

 

Now, one last question to you. stringtechno,

How much stress is there on an part of the frame that can move absolutely freely? none, right?
So, when your badmintonracket is tensioned, the postion at 3 and 9 o clock are not under any stress, as you say.. So how much do they move?
and, with all that movement, how likely is it to damage the racket?

 

@stringtechno : Thanks for the very detailed bescription on stress for Badmintonrackets.

Next question to be discussed on is the direction(top-down oder down-top) how to string the crosses to get minimum stress on the frame on a indirect and direct machine?
I'm very appreciate if you can also take it into account.

Thx

 

yup ..... now even a cheap racquet also can hold high tension thanks to load spreader ....

 

hi Kingo where did you get the kitchen cart?

 

Sam's Club.

http://www.samsclub.com/shopping/navigate.do?dest=5&item=146064