US Patent No: 8,622,096; 8,631,834 Content copyright 2020. Hansinova, LLC. All rights reserved.


Make Your Strings Bite!


Make Racquet Stringing

Faster and Easier

Frequently Asked Questions

Q: What is SpinGen used for?

A: 1. SpinGen is ideal for smooth co-poly strings such as Luxilon Alu Power and Babolat RPM Blast, the most popular strings on tour. It turns smooth co-poly strings into ideal strings for spin generation. 2. SpinGen can also be used to revive textured strings and shaped strings such as Luxilon Alu Power Rough string and Spin string. The top surfaces of these strings - in the sweet spot - usually become smooth after 2-3 hours of play.

Q: Can the racquet mounted sensor measure the spin difference before and after using the SpinGen?
A: Unlikely. Sony Smart Tennis sensor, Babolat racquet sensor and other racquet mounted sensor estimate/calculate the spin effect (not RPM) by measuring the racquet tilt angle when the racquet is contacting with the ball. They do not actually measure the RPM of the tennis ball. Therefore, even though spin strings generate more spin, if you hit with the same tilt racquet angle and swing speed, there would be no difference according to these sensors. For example, if you mount a racquet equipped with one of these racquet mounted sensors, and perform a rebound experience to measure spin effect of different strings, the result would be the same because the angle of the mounted racquet is unchanged.  
If any difference found with these sensors, with SpinGen, you might find less spin effect because you do not need to tilt the racquet as much to generate spin.

Q: What is ideal spin stringbed (strings), will SpinGen compromise string durability?

A: Ideal spin stringbed allows you to generate more spin with less effort. The ideal spin stringbed consists of:

*Main strings have 2 different surfaces:

1. Rough Side: a rough string to ball contact surface so the string can grab the ball and apply spin

2. Smooth Side: a smooth string to string contact surface so the strings can slide and snap back freely

*Cross strings are smooth all around so the main strings slide and snap back freely over them. Today's commercial strings have only one type of surface, either smooth or rough, but not both. The SpinGen is designed to make an ideal spin string bed.

Over 120 tennis players have play tested the SpinGen. These play tests have proved that SpinGen is safe to strings and does not compromise string durability. We also proved that SpinGen does not make strings lose tension by measuring the string tension before and after using the SpinGen. 

Q: The study shows that smooth strings generate more spin than the rough strings, SpinGen is to make the strings surface rougher, why does it generate more spin?

A: The reason of why smooth strings generate more spin is because the string cross sections are smoother, so the main strings can slide and snap back more efficiently for spin generation. SpinGen only makes the top string surfaces rough, it does not make main/cross string interfaces rougher, therefore the main strings can slide further and store more energy for spin generation.

Q: How does it work?

A: SpinGen provides you the ideal spin bed (strings) for spin generation. * a rougher string/ball contact surface - strings can grab the ball better, and the ball can push the main strings to slide more. * a smoother main string/cross string contact surface - the main string can slide farther over the cross string and snap back efficiently.  SpinGen treated main strings grab the ball better, this allows the main strings to "slide" further and faster along the cross strings to store more energy, where the main strings "snap-back", more energy is imparted to the ball for spin generation.

Q: Do I need to put the friction marks on the entire string bed?

A: No, only on the sweet spot of the string bed. You only need to put the friction marks on the main strings because the main strings generate most of spin.

Q: Do I need to put friction marks on both sides of the sweet spot?

A: Yes. After working on one side, you need to turn the racquet over to work on the other side.

Q: The profiled strings, MSV Focus Hex, Pro Supex Blue Gear and Babolat RMP Blast can grab the ball very well, why do I need SpinGen?

A: The profiles strings, also called shaped strings have the shape of a hexagon, pentagon or octagon. The corners of these polygons can grab the ball very well but their sharp edges usually wear off after a few hours of hitting and can no longer grab the ball effectively. "Structured (textured) strings are designed to provide better ball bite and thus enhanced spin. Most of these strings indeed offer great spin potential and in line with that better control, but unfortunately the texture usually wears within a short time and the strings become smooth. Another downside is their decreased durability. Examples: Kirschbaum Super Smash Spiky, Pacific Power Hex, Isospeed Pyramid, Prince Topspin Plus."  (  As a result, you have to hit harder to generate the same amount of spin as before. Many players often replace these strings before they break with new ones in order to keep them effective. With SpinGen, you can put the friction marks on and the strings can grab effectively again. Some said after being treated with SpinGen the profiled strings work better than when they were new.

Q: Some studies show textured strings do not necessarily generate more spin, why would strings treated by SpinGen generate more spin?

A: The traditional textured (rough) string surface increases the friction between the ball and strings, but it also increases the friction between the strings, which makes it harder for the main to slide and snap back. It is why some studies show that rough strings do not necessarily generate more spin. SpinGen only makes the outer string side rougher, but it does not change the inner surface between the strings. This will allow the main strings to slide and snap back more easily.

Q: How does SpinGen help new strings?

A: New strings are usually coated with Teflon or Silicon, such as the most popular strings Luxilon and Babolat RMP Blast, so they can slide and snap back efficiently, but the coating also makes the strings slippery and hard to grab the ball. SpinGen can increase the friction between the strings and ball.

Q: The textured (rough) strings already have a rough surface, why do I need SpinGen?

A: The popular textured strings, Luxilon Alu Power Rough and Luxilon Big Banger Original Rough, can grab the ball better with their rough string surface. But they have the same problem as the profiled strings, the friction marks wear off in a short period of time. SpinGen can make the surface rough again. Some use the SpinGen on the new textured strings, because the SpinGen friction marks are rougher, therefore they can grab the ball better.

Q: Do I need to put friction marks on both main (vertical) and cross (horizontal) strings?

A: Main strings only. Cross strings have little contribution to the spin generation.

Q: Is SpinGen legal?

A: SpinGen does not violate any rules posted by Internal Tennis Federal (ITF). SpinGen is not the same as the “Spaghetti Stringing System” which was banned by ITF.

Q: Do you have a scientific data to support your claim?

A: See "Why it Works" tab for the experiment. The experiments showed that SpinGen treated strings can generate up to 30% more spin than the same strings. The experiment is easy to set up and tested. These claims are also supported by the feedback from many players.

Q: Does SpinGen work on all strings and string patterns?

A: SpinGen works well on all plastic strings: poly, co-poly, nylon, multifilament, synthetic gut, but it is found that SpinGen does not work well on natural gut string. Do not use SpinGen on strings with a deep notch either. SpinGen works in all string patterns: 18X20, 16X20, 16X18, 16X19.

Q: The hardness of strings varies; can SpinGen be used on all strings?

A: Yes, however you need to use more force for a harder string.

Q: Is it true that the SpinGen just turns a smooth string into a textured string?

A: They are not the same. The strings treated by SpinGen are different from any textured or rough strings on the market. SpinGen only makes the string top surfaces rougher, but it does not change the interface surfaces between the strings.

Q: Which string generates spin, main or cross?
A: Mostly from the main strings. Spin is generated by main strings' "slide and snap-back" movement.