DIY Stringing Machine

derick232

Rookie
I'm sure I'm not the first one to try and make my own stringing machine, and I'm not under the impression it will somehow surpass modern machines. But after looking at several I think I can Frankenstein my current gamma 600 FC drop weight into something with swivel clamps and a better mounting system.

Here is my plan

I've only used swivel clamps once and they were great compared to my slide rails, they are my first piece to tackle. More specifically just he quick action base. The clamps will be bought. From what I can tell (and please correct me if I'm wrong) most modern turntables are simply an extruded aluminum base with slots for the T nuts of the clamp base to slide though. The lever is basically a cam that tightens the nut and locks the clamp in place. I'm currently 3D printing parts that are mocked from the gamma quick action base and we'll see how they preform. This is the first version so I'm sure there will be modifications.

Like I said, the turntable just seems to be extruded aluminum. Something I have readily available. I'm going to get 3 pieces of 40mm T slot framing and bolt them together to mock the gamma progression 602FC 3 piece turntable.

I think I'll be able to use my current base to swivel on and then it should be nearly done. I'd like to eventually upgrade the drop weight to a wise 2086 but I'm mostly doing this DIY upgrade to save money and the wise isn't cheap.

I'd like to upgrade the mounting system as the current one is not great. I'm thinking of printing new K stile mounts with press fit rods to take the place of the current bumpers.

Anyone else have experience hacking together a stringer from old parts?

Either way this will be an interesting experiment. I'll post some pictures once it's in the works.
 

derick232

Rookie
Proof of concept for the clamp base seems to work. A few minor tweaks and it should be good.
The extrusion for the turntable is cut and ready to bolt together. I'll just need to print a bushing that will mount onto the turntable and to fit over the shaft of the base for 360 rotation.
 

dak95_00

Hall of Fame
What do you believe your cost will be? How much time will it take you?

Lastly, what’s your time worth?
 

derick232

Rookie
What do you believe your cost will be? How much time will it take you?

Lastly, what’s your time worth?
Overall, maybe $80-$100 and that includes the clamps. Most of the parts I have already. As for my time, it's for my own enjoyment in my spare time so it's value is purely based on the fact that I'm doing something I like doing.
 

dak95_00

Hall of Fame
Overall, maybe $80-$100 and that includes the clamps. Most of the parts I have already. As for my time, it's for my own enjoyment in my spare time so it's value is purely based on the fact that I'm doing something I like doing.

When you finish, I hope you share a blueprint for your work.
 

jimmy8

G.O.A.T.
I bought my Alpha Axis Pro used for $450. New they are $900 + tax. With all the complex parts and moving pieces and the need to withhold so much tension, you are going to hurt yourself while stringing and/or warp/crack a racket. Just buy a used machine please.
 

derick232

Rookie
I bought my Alpha Axis Pro used for $450. New they are $900 + tax. With all the complex parts and moving pieces and the need to withhold so much tension, you are going to hurt yourself while stringing and/or warp/crack a racket. Just buy a used machine please.
I have a used machine but I want swivel clamps instead of guide bars. Besides, they're not complex and don't have a lot of moving pieces. The only potential failure in my design during tensioning would be the base clamps. Even so, it won't be a catastrophic failure and can easily be remade with more strength if needed.
 

jimmy8

G.O.A.T.
I have a used machine but I want swivel clamps instead of guide bars. Besides, they're not complex and don't have a lot of moving pieces. The only potential failure in my design during tensioning would be the base clamps. Even so, it won't be a catastrophic failure and can easily be remade with more strength if needed.
Ok, I trust you know what you're doing and nothing breaks while tensioning.
 

derick232

Rookie
I've completed the main turntable and base clamps. Only thing left is to get the string clamps and finish printing the mounting supports. All the pictures are in the google drive folder.

The one potential issue I can see if that the edges of the extruded aluminum are somewhat sharp and if they snag a string could easily damage it. I'm printing covers to go on the ends but I might have to end up putting large chamfers on the vertical corners and print some rounded corners that could attach. We'll see how much of an issue it is after the first stringing attempt. Right now the big thing is figuring out what clamps to get.
 

Irvin

Talk Tennis Guru
@derick232 i assume you’re 3D printing these clamp bases. Don’t you think they will wear out quickly? As the printing material is pliable don’t you think there be a lot of drawback?

A+ for thinking outside the box though.
 

derick232

Rookie
@derick232 i assume you’re 3D printing these clamp bases. Don’t you think they will wear out quickly? As the printing material is pliable don’t you think there be a lot of drawback?

A+ for thinking outside the box though.
What part of the clamp would you expect to wear? I've never used clamps like this before so the only portion I expected to have any wear is the shaft for the string clamp. They are fairly rigid and I have bronze bushings inserted in for the string clamps to slide on so I'm hoping they won't wear much. Infill right now is only 50% so if they need to be stiffer I can up that to 75 or 100%. And if they do wear in some way quicker than a metal clamp it's easy and cheap enough to just print more. My main concern with them is getting enough clamping force to the base to prevent movement when pulling tension, my fix for this would be to get some T- nuts with a larger surface area.

As one of the TTW stringing experts you're input is very appreciated.
 

derick232

Rookie
@derick232 Looks very nice, excited to see the finished product. I'm assuming the posts on each side are adjustable, to make changes to different sized rackets.
Thank you! And you correct, I'd like to find a more elegant way rather than having to loosen 4 bolts every time but it's not hard. Maybe eventually I'll take some inspiration from some of the machines that automatically center on the table.
 

Irvin

Talk Tennis Guru
What part of the clamp would you expect to wear? I've never used clamps like this before so the only portion I expected to have any wear is the shaft for the string clamp. They are fairly rigid and I have bronze bushings inserted in for the string clamps to slide on so I'm hoping they won't wear much. Infill right now is only 50% so if they need to be stiffer I can up that to 75 or 100%. And if they do wear in some way quicker than a metal clamp it's easy and cheap enough to just print more. My main concern with them is getting enough clamping force to the base to prevent movement when pulling tension, my fix for this would be to get some T- nuts with a larger surface area.

As one of the TTW stringing experts you're input is very appreciated.
It will be interesting to see how the parts wear over time. Why didn’t you print flying clamps?
 

derick232

Rookie
It will be interesting to see how the parts wear over time. Why didn’t you print flying clamps?
I'd never thought of doing flying clamps. I've always assumed fixed base clamps were the better option. A fully printed version would obviously not have diamond dusted teeth but maybe that's not as big of an issue as I expect. The prince universal flying clamps on TW seems easy enough to recreate. Maybe I'll give it a try.
 

Irvin

Talk Tennis Guru
I'd never thought of doing flying clamps. I've always assumed fixed base clamps were the better option. A fully printed version would obviously not have diamond dusted teeth but maybe that's not as big of an issue as I expect. The prince universal flying clamps on TW seems easy enough to recreate. Maybe I'll give it a try.
If I were 3D printing flying clamps I would base them on ProStringer Claws with metal surfaces for clamp.
 

derick232

Rookie
Quick update, I finally got some clamps and they seem like they will work perfectly. Haven't actually strung a racket yet, that will be the final step. I will post pictures in the google drive folder soon of the final design with hopefully some good results as well.
 

CVT

Rookie
This is a very impressive project. Would love to see where this goes. I'm a bit worried about whether some of the parts will handle high tension (and leverage) as well as wear and tear, but just stay safe on all of that. This clearly isn't your first rodeo.
 

derick232

Rookie
This is a very impressive project. Would love to see where this goes. I'm a bit worried about whether some of the parts will handle high tension (and leverage) as well as wear and tear, but just stay safe on all of that. This clearly isn't your first rodeo.
Thank you! Yes there have been some parts that need redesigned/ more support added to deal with the torque when tensioning. The risers for instance need 2 vertical mounting holes drilled through to prevent them from rotating as opposed to the T slot mounting bracket that allows for rotation. Another minor issues is the clamp bases are to short to support the clamps when clamped to the string, that fix is a little more straightforward, just making them taller. As for wear and tear, I think the clamp bases could eventually break down after so many pulls and such large torque applied to the necks. Luckily they are easy enough to reprint and can always be made stiffer with more infill. It might be worth it to have a few spares incase one gives way in the middle of a racket stringing. I've taken a little break from the project for a while as I haven't been playing much and some other projects have come up. But I have some breaks from work coming up that will hopefully allow me to finish it soon and give it a good test!
 

CVT

Rookie
Are you 3D printing the roller bearing for the turntable? That is an area that would really concern me as far as handling the forces.

I'll keep an eye on this thread for the time when you finish this project!
 

Bambooman

Legend
I made my own stringer with a reversed spreader clamp from Home Depot to tension the string. I made the base from a base for a jig for bike frame building with two "towers" to support the racquet via padded u-bolts.

It functions just like the EZ Stringer.

I made flying clamps with sheet metal vice grips modified with notches and notched blocks of wood as spacers.

I calibrated it with a fishing scale so I know how many pumps of the handle equals the desired tension. Hard to say how accurate the tension is but I can't tell the difference between my stringing and one done on a machine.
 

derick232

Rookie
Are you 3D printing the roller bearing for the turntable? That is an area that would really concern me as far as handling the forces.

I'll keep an eye on this thread for the time when you finish this project!
No the turntable from my old gama fc 600 has a bushing that it turned on. I'm using the original base and just attached the bushing to my new extruded aluminum turntable. Basically no change from the original.
 
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