My little tip for dropweight machines: line level

buckeye_man18

New User
I have a Gamma X-6FC dropweight stringer. I'm particular, so I was frustrated with "eyeballing" the dropweight bar to determine if it was level and thus at the desired tension. My solution was to buy a cheap line level and zip-tie it to the dropweight bar. It may seem unnecessary to some, but I feel like it's sped up my stringings and increased consistency. Anyway, I thought a few others might benefit from it. My other tabletop dropweight tip? Use an adjustable leg Keter Worktable (mine is from Sam's club). Portable. Heavy duty. Height adjustable (at least, mine is). Big enough for stringer and tools. Can be used for all sorts of other things.

Pics in action, here:

The setup


Dropweight bar with line level


Line level


Bonus tools pic
 
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ricardo

Hall of Fame
I have a Gamma X-6FC dropweight stringer. I'm particular, so I was frustrated with "eyeballing" the dropweight bar to determine if it was level and thus at the desired tension. My solution was to buy a cheap line level and zip-tie it to the dropweight bar. It may seem unnecessary to some, but I feel like it's sped up my stringings and increased consistency. Anyway, I thought a few others might benefit from it. My other tabletop dropweight tip? Use an adjustable leg Keter Worktable (mine is from Sam's club). Portable. Heavy duty. Height adjustable (at least, mine is). Big enough for stringer and tools. Can be used for all sorts of other things.

Bonus tools pic
I fully agree.
A line level is very helpful.

I have been using it for about 5 years.

I put it at the very tip.

Note:
It will definitely affect the tension (overtensioning).
If you set the reference tension @50lbs, you will actually be tensioning it at more than 50lbs.
However, since the line level only weights about 2 oz, the additional tension is negligible.

Those who are more technically inclined, pls comment on the over-tensioning.
 

buckeye_man18

New User
Note:
It will definitely affect the tension (overtensioning).
If you set the reference tension @50lbs, you will actually be tensioning it at more than 50lbs.
However, since the line level only weights about 2 oz, the additional tension is negligible.

Those who are more technically inclined, pls comment on the over-tensioning.
I assumed the weight of the level would be negligible and therefore overtensioning as a result of increased weight of the level would not be an issue?
 

ElMagoElGato

Semi-Pro
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Irvin

Talk Tennis Guru
Oh, is this the legendary thread about dropweight tensioning? I guess OP can make use of it more than I do, though. It'll take a little to remember the mathematics I learned at school.
I could be wrong but the OP's machine looks like a Gamma 'racket' machine. That being the case the racket moves in 6 degree clicks. If the bar is 3 degree low and you click up o1 click you be 3 degrees high once more and you're 9 degrees up.

What I'm saying is the chance of getting the bar perfectly level is no good. It will take forever to get the bar perfectly level for every string.
 

buckeye_man18

New User
Let me be clear: I understand the line level is not a perfect solution. It gives me some sense of consistency when I string, so that's why I feel "inclined" to use it. Others may like the idea too. If not, that's fine. Happy stringing.
 

Irvin

Talk Tennis Guru
Let me be clear: I understand the line level is not a perfect solution. It gives me some sense of consistency when I string, so that's why I feel "inclined" to use it. Others may like the idea too. If not, that's fine. Happy stringing.
Don't get me wrong, I think it's a great idea. You could use it in conjunction with a ramp and get perfect tension every time very quickly.

EDIT: I've only ever used a drop weight once and that was a long time ago but I'm guessing when you get the level right it changes, because of creep or moving the clamp, by the time you ready to clamp. Once you're ready to clamp slide one end of the stringer up a ramp until it's perfectly level and clamp.
 

buckeye_man18

New User
Don't get me wrong, I think it's a great idea. You could use it in conjunction with a ramp and get perfect tension every time very quickly.

EDIT: I've only ever used a drop weight once and that was a long time ago but I'm guessing when you get the level right it changes, because of creep or moving the clamp, by the time you ready to clamp. Once you're ready to clamp slide one end of the stringer up a ramp until it's perfectly level and clamp.
Relative noob, here. Can you elaborate on the "ramp"? Thanks.

Edit: Just saw your edit, but I'm still a little unclear. You are correct, though, the string stretches some between first leveling and getting ready to clamp (even if I pre-stretch). I usually give it a few more seconds until it's almost not moving.
 

esgee48

Legend
This has been covered before in our recorded past. The DW will be off by the difference between Cos(0) and what your final deviation is Cos(x). Since Cos(0) = 1, you only need to know Cos(x). Cos(10) = 0.985 or 1.5% which in 55# is 0.825#. I would think this is close enough for Gov't work. If you are off by 5 deg, you would be off by ~0.4%.
 

Irvin

Talk Tennis Guru
This has been covered before in our recorded past. The DW will be off by the difference between Cos(0) and what your final deviation is Cos(x). Since Cos(0) = 1, you only need to know Cos(x). Cos(10) = 0.985 or 1.5% which in 55# is 0.825#. I would think this is close enough for Gov't work. If you are off by 5 deg, you would be off by ~0.4%.
When will the DW be off? When the bar is not level or when the machine is at an angle?
 

ricardo

Hall of Fame
Why don't you just measure it before you talk about negligible? Honestly, I'm interested to know.
Multiply X by 15.

If you put 1 pound at the tip of the bar, it is like adding 15lbs to your tension.

For example, if you set your reference tension @50lbs, you are actually applying 65lbs to the strings.

In this specific example, a line level weights about 2 oz. 1 lb = 16 ounces.

So at a reference tension of 50lbs, you are actually applying 52lbs to the strings.

Is 2lbs negligible?

To me it is.

Source: Post #3.
https://tt.tennis-warehouse.com/index.php?threads/the-physics-of-a-dropweight-tensioner.170414/
 

Irvin

Talk Tennis Guru
Multiply X by 15.

If you put 1 pound at the tip of the bar, it is like adding 15lbs to your tension.

For example, if you set your reference tension @50lbs, you are actually applying 65lbs to the strings.

In this specific example, a line level weights about 2 oz. 1 lb = 16 ounces.

So at a reference tension of 50lbs, you are actually applying 52lbs to the strings.

Is 2lbs negligible?

To me it is.

Source: Post #3.
https://tt.tennis-warehouse.com/index.php?threads/the-physics-of-a-dropweight-tensioner.170414/
Why don't you come over and spread some of that 'stuff' on my yard I need some good 'stuff.'
 

Irvin

Talk Tennis Guru
Master, I just quoted the link that you yourself posted (#7, this thread).

I always assume you are posting reliable links.
I think you misunderstood post #7. What I posted was about the error if the bar was not level. I doubt very seriously a line level weighs 2 ounces but if it did the tension added to the string is mass times beverage. If the level were placed bear the gripper it adds 2 if of tension. It would be more the farther out on the bar you go.
 

ricardo

Hall of Fame
I think you misunderstood post #7. What I posted was about the error if the bar was not level. I doubt very seriously a line level weighs 2 ounces but if it did the tension added to the string is mass times beverage. If the level were placed bear the gripper it adds 2 if of tension. It would be more the farther out on the bar you go.
This is the link you posted Master:
https://tt.tennis-warehouse.com/index.php?threads/the-physics-of-a-dropweight-tensioner.170414/.

This link, post #3, contains the following:

---------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Another thing people ask is, what if I push down the bar to the horizontal position?
I took an quick measurement with my dropweight machine. The radius of the tensioner is about 1.2 inches, and the length of the tension bar is about 19 inches.
If I apply a force of 1 pound at the end of the bar to keep the bar horizontal, I'm over-tensioning the string by nearly 15 pounds!!!

How did I come to this conclusion?

Look back to this equation:
f x r = M x g x R

If I apply 1 pound at the end of the 19-inch bar, I will add an extra torque of 19 pound-inch on the right side (torque). That's the same amount of torque the left side has to come up with. Since the "r" for the left side is only 1.2 inch, the extra "f" it will have to have is about 15 pounds (the ratio of the 2 radii: 19 inch divided by 1.2 inch)!

If you have a stiff poly and you're pushing down by a force of 2 pounds, you're over-tensioning by over 30 pounds! It can easily break!

--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


I merely quoted the above statement in Red.

You posted this link yourself Master so I believed it.

I was not aware it is 'manure', like you poetically say.

I have to be more skeptical next time.
 

ricardo

Hall of Fame
I could be wrong but the OP's machine looks like a Gamma 'racket' machine. That being the case the racket moves in 6 degree clicks. If the bar is 3 degree low and you click up o1 click you be 3 degrees high once more and you're 9 degrees up.

What I'm saying is the chance of getting the bar perfectly level is no good. It will take forever to get the bar perfectly level for every string.
I agree/disagree Master.

It you use the racheting mechanism, I fully agree that it is very rare that you can have perfect level, especially with very stretchy strings like Monogut ZX.

However, you don't have to use the racheting mechanism for all strings.

If I string poly (poly do not stretch much), I don't use the racheting mechanism at all and I can get perfect level everytime.
 

seekay

Semi-Pro
If you're worried about the level adding tension, you can attach it as close to the pivot point as possible. That will reduce the torque applied by the level's weight, maybe enough to call it negligible.
 

ElMagoElGato

Semi-Pro
If you're worried about the level adding tension, you can attach it as close to the pivot point as possible. That will reduce the torque applied by the level's weight, maybe enough to call it negligible.
What a good idea! That's perfect.

Multiply X by 15.

If you put 1 pound at the tip of the bar, it is like adding 15lbs to your tension.

For example, if you set your reference tension @50lbs, you are actually applying 65lbs to the strings.

In this specific example, a line level weights about 2 oz. 1 lb = 16 ounces.

So at a reference tension of 50lbs, you are actually applying 52lbs to the strings.

Is 2lbs negligible?

To me it is.

Source: Post #3.
https://tt.tennis-warehouse.com/index.php?threads/the-physics-of-a-dropweight-tensioner.170414/
The difference of 2 lbs is not negligible at all to me. I normally steps through by 2 lbs when I look for a right tension. Even 1 pound matters if it's a poly of 1.25 gauge or so. But then if the thing is always there, it's consistent anyway. I'm more worried about the difference up to 0.4% by 5 degree of the bar. It's also a 2 lbs difference if the reference tension is 50 lbs. And it could be inconsistent string by string. Drop-Weight stringer definitely should have a line level on its bar.

EDIT: Well, 0.4% is only 0.2 lbs. Shame on me.
 
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Irvin

Talk Tennis Guru
This is the link you posted Master:
https://tt.tennis-warehouse.com/index.php?threads/the-physics-of-a-dropweight-tensioner.170414/.

This link, post #3, contains the following:

---------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Another thing people ask is, what if I push down the bar to the horizontal position?
I took an quick measurement with my dropweight machine. The radius of the tensioner is about 1.2 inches, and the length of the tension bar is about 19 inches.
If I apply a force of 1 pound at the end of the bar to keep the bar horizontal, I'm over-tensioning the string by nearly 15 pounds!!!

How did I come to this conclusion?

Look back to this equation:
f x r = M x g x R

If I apply 1 pound at the end of the 19-inch bar, I will add an extra torque of 19 pound-inch on the right side (torque). That's the same amount of torque the left side has to come up with. Since the "r" for the left side is only 1.2 inch, the extra "f" it will have to have is about 15 pounds (the ratio of the 2 radii: 19 inch divided by 1.2 inch)!

If you have a stiff poly and you're pushing down by a force of 2 pounds, you're over-tensioning by over 30 pounds! It can easily break!

--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------


I merely quoted the above statement in Red.

You posted this link yourself Master so I believed it.

I was not aware it is 'manure', like you poetically say.

I have to be more skeptical next time.
Not sure what you're talking about but here is a link to post three in the thread you linked
https://tt.tennis-warehouse.com/index.php?threads/the-physics-of-a-dropweight-tensioner.170414/#post-1927812
That is not me
 

max

Legend
A number of years ago on this forum some student calculated that there is a plus/minus of three degrees; be in this range and your tension will be fine.

I work by that idea.

I've had a line level, but I'm satisfied with my experienced eyes on the thing.
 

eelhc

Hall of Fame
Why don't you just measure it before you talk about negligible? Honestly, I'm interested to know.
I did this when I had a dropweight with kevlar strings and a luggage scale... Just eyeballing is good enough. Keep in mind that with a ratcheting dropweight, there's a discrete step. Going that 1 ratchet because the level isn't exactly flat may result in it going too far.

If the level makes the OP feel better that's cool... but really, eyeballing is just fine.
 

ElMagoElGato

Semi-Pro
I did this when I had a dropweight with kevlar strings and a luggage scale... Just eyeballing is good enough. Keep in mind that with a ratcheting dropweight, there's a discrete step. Going that 1 ratchet because the level isn't exactly flat may result in it going too far.

If the level makes the OP feel better that's cool... but really, eyeballing is just fine.
Now I see the difference is small and the operation is easy enough. OP says he's sped up his way. If the level helps in that, I guess it's got good value.
 
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