Drop Weight Stringers ... Help Please

[Phil]

I have a drop weight machine (Eagnas Hawk 80). Should I let the weight go from the vertical and allow it to drop on its own to the horizontal (as the manual implies) or should I support the weight with my hand and control the speed it drops at (i.e. so it falls very slowly) as Maxline have suggested in an email.

I assume the two different approaches would have a dramatically different result in terms of the resulting tension and the characteristics of the string - given that the first method would inevitably result in pre-stretching. Please help - at least let me know which technique you favour.

Thanks in advance

Phil

[Jens]

You have to support the arm a little bit, do not let it "crash" down.
Where did you read that the arm should drop without support?

[Phil]

The manual says "let the tension rod and weight fall by themselves" which I appreciate is a little ambiguous. I would assume that the weight is going to pull to a different place (i.e. further) if it gathers momentum on the way down, so presumably the tension I'll get will be slightly different if I support the weight - also I won't be pre-stretching so much. Any thoughts? (Thanks, by the way)

[SteveT]

Hey Phil,
I have read several of your postings. We both have the same stringing machine if I'm not mistaken (Eagnas Hawk 80). I have experience similar problems with the drop weight on this particular machine. The first time I strung with this machine I could not get the drop weight to rest at the horizontal unless there was an extreme amount of string tension to finally hold the drop arm horizontal (at times the string would slip out of the clamps). I then started to rest the drop arm in the horizontal position by sliding an Allen wrench just under the bolts that secure the drop arm to the post (I would need to show you a illustration in order for you to imagine this). After about 2 racket restringing jobs, I noticed on my 3rd string job that the drop weight magically began to perfectly balance at the horizontal after the proper length of string was pulled (without using any aid from the Allen wrench). The machine began to work beautifully for my next 4 racket jobs. I attempted a job last night and again I had problems with the drop weight. I'm not sure what causes this problem, but I can "feel" the difference when the drop weight arm is pulling properly & when it is requiring to much tension to finally come to rest in the horizontal. That is probably why the stringer is stringing 7-10 lbs. higher than it should. I can't figure out yet what could be going wrong mechanically when this happens, but I do know what it feels like when the stringer is working properly. When working properly the stringer is very efficient and accurate. Hopefully we can stay in touch & try to come to some kind of resolution on this strange issue.
Do you have any thoughts Joe?

[Jens]

Please neither do any of the following things:
1) Do not let the rod fall down without any support from below. This will cause serious stress on the string and racquet, also the tension will not be correct.
2) Do not apply any force in case the rod does not come to rest in the horizontal position.

I don't know if I got you right, Steve. Are you saying that you are adjusting the weight on the arm to make the arm rest in the horizontal position??
Depending on how loose or tight you insert the string into the string gripper, the arm will come to rest in different positions. It also depends on the type of string you use. Please read the manual on this website, it says what to do when the arm does not come to rest in the horizontal position.

[SteveT]

Hey Joe,
Well technically I'm allowing just enough slack in the string to allow the drop weight arm to come to rest to the horizontal with the aid of my Allen wrench as support (to hold it horizontal). Otherwise the drop weight arm would drop below horizontal. The problems that Phil & I experience seem to be inherent in the stringer itself. If I try to allow the arm to slowly drop to the horizontal by its own natural inertia (with slight support of my hand) it would require an extremely high amount of string tension to hold it in the natural horizontal rest (this is also why some customers are experiencing out of range string tension of 7-10 lbs). Of course using my Allen wrench support convention brings about inaccurate tension, but it has prevented string or racket damage in the mean time. Like I said earlier though, I have had 4 previous racket restring jobs that worked flawlessly using the proper technique for drop weight machines and had absolutely no problems (and this was with using the exact convention described in your stringing tips section). I can't figure out why this last string job has been giving me trouble again. I will continue to troubleshoot the machine itself & double check my technique. Hope this clarifies. :)

[Jens]

But once the arm has dropped below horizontal, you can always hold the string gripper and move the arm back upwards. Or is this impossible with your machine?

[SteveT]

When my machine is "acting up" like what it has been doing lately it's almost impossible to adjust the string and get the arm back upward to horizontal.