Discussion in 'Racquets' started by travlerajm, Mar 29, 2008.
If someone builds a racket with Superpowers, and noone sees it, does it actually exist?
I injected 754 grams of viscous fluid inside my SV PS85. SW has been bumped to around 830. My fh stroke has decreased from a full swing to a mere 6" tap.
My racquet's "dynamic stiffness" has now caught up with the "static stiffness". My electromotive acceleration is now .55 and my off-center of percussion is somewhere near my buttcap!!
However..... my NTRP remains the same
Add 30 weight oil at 12 o'clock until SW reaches 1,000 and repeat slowly the following chant: o wa ta ful iam and you will soon find yourself on the pro tour!
Could someone tell me how to calculate the "recoil weight".
According to Prince, Recoil is 16g. I don't know if that's gauge or grams or gerbils.
Is it fair to say this thread has unraveled, or has it gone to its rightful place? Perhaps both?
I think all these nonsense comments are sad. These threads do contain some useful information. Sure it is not everyones cup of tea but to modify a racquet can actually have big benefits and it is fun aswell.
I have once said on a Thai religion board:
"Light cannot help those with closed eyes see."
Thanks travlerajm. I have always enjoyed your posts and I am benefiting greatly from them. I have printed out your stuff from waaayyy back. Thanks again. And, if you have time and find your camera cord, I would love to see a pic.
Make sure you can handle the increased weight and swingweight.
The last time around, a lot of people modded their racquets, only to post later about their injuries and how they had gone back to their old setups.
Yeah, these threads contain useful information like this:
Neither the time period of the swing of the pendulum nor the speed at any point on the swing depends on the mass of the pendulum. The time period depends only on the length, and the speed at any point depends only on the height from which the pendulum was released.
This is for simple pendulums. For compound pendulums it is different. It depends on the moment of inertia and the total mass.
Thanks, sureshs -- finally some defensibly correct statements in this realm!
Ahhh, but therein lies the rub! Given a human arm holding a racket and acting like a fancy compound pendulum, how much slower will this system swing when we add a few grams to it? How many grams does it take to make this system actually slow down a meaningful amount?
It's all fine and good to wave your hands around, but to show that the hand waving of a tennis stroke somehow becomes gravity-governed by adding a few grams of mass, you will need to show that the moment of inertia of the arm-racket system is significantly increased: good luck with that....
(Ever notice how slow your arm falls when holding a shotput? Me neither.)
Pseudo-intellectual threads that attempt to baffle with BS since they cannot dazzle with brilliance do not deserve to treated with the reverence that would be granted to a newly discovered paper by Einstein.
Even some of Einstein's theories weren't completely accepted until YEARS AND YEARS after he died.
Travler, I have learned lots from you over the last year or so. Thanks again.
If you learned stuff like this:
Well, you might want to check that with someone who took (and passed) a high school level Physics course....
?? General relativity, Einstein's most famous and important work, was experimentally confirmed in 1919, making Einstein a world-wide celebrity from that point on. He received the Nobel Prize for physics in 1921, living until 1955. I have no idea of who you are confusing him with.
I've recently been enthralled in SW2 and polarization stuff within the past 2 - 3 weeks, and after reading countless posts, I decided I'm ready for lead in my AG200's.
I've got 12 g of fishing weights in the handle right now, but ill probably take those out when my lead tape comes in (monday). Im planning on doing the standard practice of putting a long strip along the hoop between 8 and 4, Then putting another 5g or so at 12 until I get enough SW. I'll then replace my fishing weights, though not all 12g worth.
My question is, is there a blatant step I've missed, or does somebody have a better approach for polarizing a 12.3 oz, 11phl frame? Thanks everyone for providing all this info.
You can not have two raquets with same static weight, same balance,same swingweight and different weight distribution.
I tried all setups of Trav. (SW2) including his NXG OS and I don't think they work for a club player. You don't have to much directional control.
His desire to play with that high swingweight it comes from the fact that he uses kevlar strings which are very low powered.
I can have better results and directional control with a raquet with 322 sw and Natgut/poly hybrid.
travlerajm do you have recommendations for customizing the LM Radical MP and dunlop 300g? (Polarization setup)
dang it, just when i was going to order a POG LB, they ran out of my grip size and TW have discontinued selling it.
Anyone know another racquet that is perfect for polarization?
I prefer to just use a standard racquet...something about that extra inch that helps me hit better shots....I guess you also could tape a tennis ball launcher to a junior racquet and blow people off the court...wait, you could even just build the superracquet and create a computer program to test it and play against and not even go to the court...
How to calculate SW "after" lengthening a frame?
Travlerajm, I'm just curious:
So you where able to calculate the SW of your POG LB after the shortening of the handle. Now I was wondering, how do you calculate SW after making a frame longer?
I'm basically interested in doing the opposite of what you're doing. I'm thinking about using a 26" Junior frame with a low SW. Another member has already done
this before (I forgot who).
Let's say that the starting SW at length 26" = 240. What would the new SW be after adding an extra inch? BTW, the added length's mass can be disreguarded as far as for SW calculation, since it's static weight is very minute, plus the location of the added length is close to the axis of rotation anyways.
I would greatly appreciate your help or anyone's. Thanks.
I believe in another some guy asked how to calc the SW. And you need to find a bunch of stuff and put it in an equation. THere's also a spreadsheet where you just put int he input of your new racquet balance from balance to handle and balance to hoop and a bunch of weights in grams and it will calc your SW.
This should help. I also have done this on a spreadsheet. You will still need to measure the balance of the racquet and may need to counter-balance to maintain the same balance.
Good question, I was wondering the same thing!
The simplest way is to first convert to recoil weight (swingweight about the center of mass). Recoil = Ic = I - M*(R - 10)^2.
I = swingweight about 10cm axis.
M = mass in kg
R = balance in cm
Then, if you want to lengthen by one inch, you convert back I.
I = Ic + M*(R - (10 - 2.54))^2
So for example, if starting I = 240, M = 280g, and R = 33.
Then Ic = 240 - 0.280*(33 -10)^2 = 92.
Then for 27", new I = 92 + 0.28*(33 - (10 - 2.54))^2 = 274.
Reopen the St.Vincent Factory
What I did before was I used the calculations of your POG's before-after specs as a guideline for an estimate of the SW estimation.
Your "before" spec was: POG at 28" = 320
"after" spec was: POG at 27" = 285 (approx)
I then subtracted 285 from 320 = 35
Then I added that difference to the SW of my frame: 35 + 240 = "275"
I ended up with an estimate close to the result of your example the frame with SW 240, balance at 35".
You had "274" and I had "275" -- really close est.
I know that there is the other variablew to take into account, which isthe balance point, but in my previous estimate, I figured I would come up with a ballpark figure that would at least give me an idea as to what I am looking into.
Thanks to you, now I know how to make more precise calculations by using the formula you provided.
trav- Compare your opinion of the "Superpower" stick to the SW2 NXG.
@travlerajm: just wanna thank you for all this info you provide.
Good ideas you have about tunning rackets.
Most of this ideas are already used since the 90's by ATP players, but are secrets for simple players like many around here.
The rest of you guys that keep telling stupid things about travlerajm, just open your eyes and your mind a little...
Listen I am one of the people that has done this since Trav first brought this up, now I have tried this on 25 different rackets and different setup.
There is a HUGE advantage when a racket is properly setup and let me tell you, that what you buy from the manufature 90% of the time is crap!.
There simply is no comparision, and the only people that don't believe that are the people that have not tried it.
Trav and I disagree on the application, and I broke up the differences in racket specs for the different styles of play.
So there is not one fits all customization, as that is not possibile LOL
If you look through so me of my old post you will find that, how ever the basis of what Trav is saying is 100% true.
Or you can agrue with the pros rackets which Greg is more than happy to do LOL
Perhaps Greg would also have you believe that a co-poly is just like any other old string that has been around LOL
Not only that .... it's also the people that aren't doing something right or just aren't technically inclined (some people just aren't good at fixing things and getting things right -- hands-on).
Would say there is a correlation for height and weight to determine your optimal swingweight? So say 5'6 & 140lbs.
Absolutely true, no argument possible, though perhaps the notion of HUGE is a tad bit exaggerated.
Totally false: the manufacturers build quality products; the fact that they aren't optimized for your particular stroke doesn't make them crap. Fact is, the vast majority of people can play quite well with a stock stick right out of the box. Further, the fact that stock rackets vary quite a bit in terms of mass isn't much of a problem, either: it's only really a problem if you want/need matched sticks, which is a small minority of the racket-buying public.
Sorry, wrong: the basis of what Trav is saying is total BS. Here's his explanation of the logic behind SW2 (I'm conveniently including the link to the post so you can go look up the thread/post and see for yourself):
Anybody who has ever taken HS Physics knows that the above is totally incorrect! Unfortunately for you and travlerajm, the above is the whole foundation of the SW2 nonsense. Oops.
As far as the pros, if you spend time with a professional MRT, particularly one who works with top 20 pros, you will find out how and why the pros customize their rackets. And as I have done this, I have found -- surprise, surprise -- that SW2 is not a factor, not even close. The real process is simple and works well as is quite obvious from the results they get. No, I won't post what they really do, but I'll tell you that there is no secret formula, no secret handshake, no magical mystery behind the customizations -- and yet, it's not surprising that pro rackets end up closely comparable in swingweights, etc....
And yet you are making this like those very magicians who guard their stage secrets - precisely the point I guess.
Ok let me try to deduce...
It's not about SW2 mass, although matching the mass of multiple racq is a required.
Hmm, so it's a process whereby pro racquets end up all somewhat close in SW which isn't a process do with adding or subtracting mass. Perhaps it's about where the mass is situated?
I imagine the process is about getting the pro to hit balls spat by machine at certain "pro" speeds and see if they are returning long or short; and then move weight up or down. It doesn't matter whatever chosen racquet the pro starts with, whether they start with a light static weight or heavy, the pro at least knows what weight they can carry. Tuning their strokes this way would still be tuning swingweight though... um?
Well if that's my guess at the "how", then the "why" would be about inbuilding certainty and ironing out error.
Say what you like about SW2, I think the focus on swingweight is beneficial.
And perhaps the addition of the new TWU(niversity) with it's lessons about stringbed power etc are exactly trying to address such "magical mysteries".
i'm extremely interested in trying this. will probably pick up a racket this week and start the sawing and weighting.
My actual hitting impressions.
I have no idea if these swingweight calculations are correct, or if you even can, as many other posters have questioned or refuted, calculate swingweight by using weights and balances. Nor do I have any opinion as to how SW2, if real, applies to different swing types such as high take backs and low take backs (the Cauthon method?). This is just a post to tell of my experience using the significant weight increases as discussed on this thread. I also wanted to share my experience as it relates to the numerous questions as to if a non-pro player could wield a racquet with a high static weight and with what results.
Racquet = new from TW, Prince Graphite Classic Mid, 600 cm. sq. head, length 69 cm., strung weight with Gamma double worm dampener and overgrip 346 grams, approx. swingweight 328 (the addition of the dampener and overgrip may have changed that a little, but it can’t be much), listed on TW as 8 pts. headlight and balance on Prince website is 31.0 (a little confused on this calculation input as the Excel conversion program had 8 pts headlight = 32 cm; I guess I could use a Viper board), stiffness 66, strings Lux. BB ALU Power Rough mains @ 57lbs, Prince Premier Softflex crosses @ 57 lbs. I used the Excel calculation program provided in another post and tried the following setup: 4.5g @12, 4.5g @ 10, 4.5g @ 2, 13.5g @ bottom of handle to counterbalance. I used the new Gamma lead weights that are shaped like an “H” and have a black exterior instead of the traditional ¼” lead tape strips. The “H” lead pieces are 4.5g each according to my scale even though TW lists them at 3 or 4 and they put the weight on the frame in just under a 2” space rather than the longer strips of ¼” tape. I have no idea how the space concentration of the tape weight affects the calculations or hitting experience. The Excel program gave me these new figures: mass 373 g, Balance 30.8, Swingweight 360, Iref 198, Power Level Index 2209 and SGPR 1.15. I don’t have a completely clear concept of Iref, PLI and SGPR, but let me tell you how it hit.
Fantastic. I am not saying you can make an “Excalibur” racquet, but it is the best racquet I have ever hit with. The other racquets I have played with for long periods of time in the past are Wilson PS85, Head Prestige Classic and LiquidMetal, Volkl C10 Pro, Slazenger X1, Yonex RDS001 Mid and Yonex RDS002Tour. The racquet was extremely solid on groundstrokes and volleys and it was soft feeling, maybe “buttery” is the better descriptive word I have seen in different descriptions in the forums. The soft isn’t a negative term, but a compliment. Comfortable, no twingy feel or vibrations. Great combination of power and topspin, much better than what I had been hitting. I needed to make a slight adjustment to hit through the ball and hit out in front, but that was really it. Forehands (flat, inside-out and crosscourt) were great, i.e. much better (harder, heavier and easier to accomplish) than with my current setup (Yonex RDS002 Tour, same strings, 12.2 strung, listed swingweight 330). Backhands took a little more time to adjust to, but I started to get the hang of how to change my swing to get flat and top when I wanted either. The 373 g (13.2 oz.) weight did not cause any problems during or after 2 hours of hitting. Volleys were better than with my normal setup as well; good power and able to use touch as well; not sure about reactive maneuverability as I was at net expecting volleys as practice. I will have to be in more doubles type reactive situations to give a more accurate assessment on maneuverability.
Overall, a great change for me. All aspects of my stroke results improved and I cannot say there were any negative points resulting from what was pretty much an extreme addition of weight. I’ll be setting another racquet up just like it as soon as I can verify that my serve hasn’t gone to the dogs with this setup.
Regardless of whether you believe SW2 or that sw can be calculated by using weights and balances, the effect for me of adding weights at the locations discussed in this thread, which is obviously verifiable using my scale and not just some physics theory, was great for my game and may be worth a try for you and don’t be afraid of the extra weight if counterbalanced.
Great that you ended up experiencing positive results.
Some people experience negative results, perhaps because they mod was just terrible (in relation to their style, strength etc), or that perhaps they aren't able to adapt to the new dynamics of the setup.
Sometimes (depending on the mod) you have to alter your mechanics -- this may be good or bad, depending on what the player is willing to do. Whether or not you're forced to alter your mechanics, I think that any mods done to a frame will force you to at lease adjust/adapt to the new feel.
So, give mods a chance for a while. After that, if you still don't like it, remod it or just go back to stock (stock form may be the optimum setup for some).
traverajm, what is your height and weight? I understand your ideal swingweight for you is 360 so I'm trying to figure out a relative relationship.
Excuse my ignorance but in reference to travlerajm's first post on this thread what is the 'tapered part of the buttcap'
if this a butt cap:
what part is the tapered part?
Isn't a buttcap a simple piece of hexagonic plastic that seals the end of a racquet? Does the author 'travlerajm' mean and is suggesting the tapered part of the handle?
I first removed the leather grip.
Then I pried out the staples and pulled off the buttcap.
Next I sawed off an inch, replaced the buttcap.
Then I resecured the buttcap with staples
The above doesn't make sense to me. Why saw off one inch the grip then put it back again?
Instead, I wrapped ¼” strips transversely around the frame between the grommet holes, to form multilayered rings. Each ring weighs about 2.7g, with 12 rings total. I have 5 rings between 1:30 and 3, at every other space between grommet holes (so that the rings go around only the spaces where there is no string on the outside of the frame). And another 5 rings between 9 and 10:30. The other 2 rings are at 11:30 and 12:30. Then 1 more gram was added in the standard way at 12 o’clock to tune the swingweight. The rings don’t fly off when I swing because they are mechanically attached.
How do u 'mechanically' attach lead strips on to a tennis frame? It is impossible to attach leads loops on a frame securely as the surface is not flat, as the grove which harbours the 'grommit' holes does not allow this.
Could anyone explain my queries cos I am clearly stupid.
Basically it's the narrowing section of the cap.
In that pic you posted, the "entire" object is the butt end cap. The cap "isn't" just the piece that pry's off conveniently -- that piece is called the "TRAP DOOR" and only some frames have that readily available.
OK, after reading the remaining part of your post, I'll let someone else shed light. You did not seem to fully ready Trav's thread. He explained why he choose the frame that he used as well as why it was to be sawed-off.
No you see this is where I and Trav differ. Trav feels that a racket should only be one way with a little variance.
Weather you know it or not head heavy/ hammer rackets were one of the most amazing rackets ever made. There are many different setups, it just depends on the player.
So your racket does not need to be Trav's specs to get those kinds of effects.
I will share one of my latest rackets some time this week, it is absolutely amazing.
It is not easy, every racket is different and you can't get every racket setup for each style of play, some simply can't do all of them and some non at all.
If you had bothered to read all his posts in this thread, you would have understood why. He sawed off an inch of the HANDLE not the grip. The racquet was 28 inches stock so he took it down to 27. He never said anything about grip. (You remind me of the stupid Americans which is why there's idiotic warning labels everywhere for everything).
And by mechanically attaching, he means wrapping it around the frame instead of just taping lead tape along the inside of the frame or inside the grommets.
I just thought of a problem. How do you wrap the lead tape evenly? Because the stringing of the crosses makes it staggered so lead tape at 9 and 3 won't be exactly face to face. It will be off by one cross face.
don't know if you guys can see it clearly but the black squares are each grommet and the red is the string. Hopefully you can see what I mean by how the crosses are staggered.
So how do you wrap the lead tape so that it balances out correctly? Or is being off by 1 cross space negligible?
My recommendation would be to NOT wrap the lead around in the x-string area (I wouldn't even wrap it around the mains, doesn't look professional). Just apply the tape "normally" around the x string area (it won't fly off, unless you add like a chuck of 1 ounce in a tiny concentrated spot).
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