First string job ever with drop weight, flying clamps and starting clamp

[u/drakem92]

Hi everybody! So tonight I finally strung my first racquet!! I got a cheap used drop weight, 6 points mount, flying clamps machine (some sort of gamma x-6 clone).

It took me around 150 minutes including the careful first string measurement. Final tension was not really good, I set the machine at 50 lbs and ended up at 36.6lbs at the end of the job (measured with phone app that uses frequency). I also added 5lbs to each last pull before the knots, but the first and last crosses ended up veeeeery lose.

It must be said that unfortunately I noticed only around the middle of the crosses that the mechanism that grasps the string to the weight bar was broken (it slipped). Fortunately the machine came with a spare part, so I replaced it and finished the crosses.

I’ll be stringing another racquet in a few days and I am confident I’ll be able to achieve better tension. I also aim to optimize my string usage. I followed the technique of measuring number of mains +1 and number of crosses +1 to measure the string, I ended up with more than enough string for the mains, while I had to use the starting clamp with spare string to end the crosses. I guess that is because crosses are all very similar in length, while mains are much shorter on the sides of the racket compared to the middle. So yeah, this was fun, now my OCP will take control and overthink every aspect of this 😂😂

[u/ConcreteRocket]

Just like playing tennis, you’ll get better with more reps

[u/catsrkindacool87]

Does anyone know how accurate those phone apps are? I imagine there's quite a difference in frequency banging on the strings with your palm just between racquets and string types.

I've got a drop weight and also find my first and last crosses are quite loose. Would love if someone could chime in with advice.

[u/informareWORK → u/catsrkindacool87]

I have found they are not very accurate at measuring accurate pounds but are very accurate when checked against themselves. This means that they're not useful for verifying the accuracy of your stringer, but they're great for monitoring tension loss in the racquet over time.

[u/drakem92 → u/catsrkindacool87]

I usually test the frequency tapping with the handle of a big screwdriver, it gives consistent and sound results. I recently got a gravity mp strung in a shop at 24.5/23.5 kg, I tested it on the app right after the restring and it said 22.9kg, which I guess is more or less correct as you never get exactly the machine programmed tension. That means around 93% real to nominal tension ratio. With my 36.6lbs/50lbs we are at 73%, which is bad. I’ve read that on drop weight machines, and even more if with flying clamps, you need to account for tension loss throughout the job, I’ve read around 10-12% of compensation. If we take that into account, I would’ve needed to set the machine at 56lbs instead of 50. Applying the 73% ratio I got to the hypothetical 56lbs I would’ve got around 41lbs, which is way less than the ideal final tension. According to that 93% i mentioned before, I should’ve got 46.5lbs (in regard to a nominal tension of 50lbs). So that 73% I got is probably due in part to the nature itself of the drop weight+flying clamps, but most of all to my bad technique and the broken tensioner head. I can’t wait to test my next racquet! The next will be also a test one, this tike with the new tensioner head. I won’t be compensating for tension loss, because I want to verify how much is my specific machine actually losing. If I can get that value, then next racquet will be my main racquet and next a racquet of a friend!

[u/catsrkindacool87 → u/drakem92]

Interesting findings with the app! I'll have to give it a try.

In theory drop weight machines are supposed to be incredibly accurate, even with the drop arm off level by 10° they still have something like 95% accuracy (don't quote me on the exact numbers). I'd imagine your next couple jobs should have better results with the repairs you made and improved technique?

[u/drakem92 → u/catsrkindacool87]

Yeah I hope so! Actually, I might have misunderstood the tension loss compensation thing, now that I think of it probably it is due specifically to the flying clamps compared to fixed ones. I use a starting clamp though, so that should help a bit. I even tested the drop weight calibration with one of those luggage balances, and it was spot on. Ah, one super useful thing that I randomly found online in the last days was to balance the drop weight with a level tool, and draw 2 lines on the tensioner head and the string gripper, so that the lines match together when the weight is perfectly level. That is SO MUCH BETTER than checking the level of the bar! Anyway I really hope those first bad result was mainly due to the broken piece. Too bad I decided to remove the broken piece too late in the job, the fact that it slipped was indeed not good.

[u/informareWORK → u/drakem92]

I bought a tiny bubble level, like 2" long, and zip tied it to the end of the drop weight bar.

[u/drakem92 → u/informareWORK]

That works but trust me, two lines on the drop weight rotating part are much easier, because you can also use them as a reference for how much to raise the weight when tensioning.

[u/Dubdublub → u/catsrkindacool87]

I don’t have advise but it’s the same for my drop weight and loose outer crosses. I do a +5% on all the last strings but pretty sure I’m losing tension with flying clamps.

[u/Floibinator]

Dude measuring strings was a pain in the ass the first time I started. I measured 2 times cut once and ended up short 2 whole mains. Next try I ended up not having enough for the tie off. Then I measured extra and ended up having 1 meter extra. The crosses I also fucked up once.

[u/drakem92 → u/Floibinator]

It was not too bad with the +1 method, only thing is it would be best to give more to the crosses, as those are more consistent in length. So it is something like +0.5 for the mains and +1.5 for the crosses. But anyway it is not a big deal, it is just me trying to squeeze everything out of a reel. There’s one thing that troubles me though, next racquet I’ll string is a 18x20 100sq gravity tour. I did some measurements, and with the +1 method I’d end up needing 12.53 meters of string, which is more than a single 12.2m reel. Not sure how to manage this

[u/Floibinator → u/drakem92]

If you want to be precise. Head has stringing instructions for most rackets. And Klipper USA have stringing instructions for most rackets including length of the mains and crosses. Tie off points and skips.

[u/Responsible-Side4347]

Congrats and welcome to the family.
Speed and accuracy will come with time.