This may not be a news for some but i just recently discovered this and would like yo share it here. I have two stringing machines, a 5 year old Fleet and a recent precision 5 Yonex. It always baffled me although the both machine calibrated equally and the string bed tension from Yonex is always a tad higher than 5 year old machine. The difference is a little obvious from string bed pinging sound. Came to realise the Yonex machine brakes slightly later than the Fleet machine. I suspected the auto brake early caused the string to pulled against the grommet at extreme angle, causing the string inside the frame to lose tension. So we tried disabling the autobraking function and string the same tension same string and racquet. The outcome is as suspected, same string bed tension from both machine. So yea, turn off autobraking for more precise tension. If youre about wobbling of the turntable, tension the string with your hand first before engaging the tensioner.
For me, the autobrake is not a good function. Similar to the half/full automatic clamp base (open and drop clamp to release the base). You can do more wrong with the autobrake function than with the wobbling.
That's interesting to hear, but it doesn't seem to happen on me. I had strung 3 Ryuga II after seeing the post with auto brake on for 1 racket and auto brake off for 2 rackets. All 3 rackets were measured with ERT 300 right after stringing and turned out to have the same value. I have only the Victor machine so not sure what the value measured with ERT 300 will be with Yonex machines.
It probably varied with how early the autobrake being engaged. This can be avoided by allowing turntable to rotate fully into position before engaging the tensioner. Or, avoid autobrake all together.
That makes perfect sense. But probably never been mentioned as most of us don't own 2 machines with different auto brake (or even have an auto-brake at all for that matter!) Good stuff though.
Update: Ok its just hit and miss with the pinging sound. For some reason the pinging sound sounds lower on the older machine and string bed tension tester shows same value.
When I went to Toyozouki, they explained to me why they didn't have autobrakes on their machines Protech series machines, and it was for that same reason. When the string is pulled they want the leas amount of friction pulled against the grommet, leaving the mounting system to move freely to achieve that angle. With an autobrake sometimes that angle cannot be achieved consistently, so Protech machines never had an autobrake. Not sure why Precision machines were made with an autobrake but my thoughts were because tennis stringers might have requested it, for some rackets and string, an autobrake is helpful, so maybe they decided to make a machine with it. Also probably the premium price and bells and whistles made it a good selling point for the machine. Most machines at major tennis tournaments have an autobrake function now-a-days. Sent from my SC-01L using Tapatalk
Got a tension calibrator and tested the effect of stringing grommet angle against inside string tension. Result is behaved as expected but marginal. No grommet pass through 20lbs : 19.9lbs ~10 deg 20lbs : 19.13lbs ~45 degree 20lbs : 19.26lbs ~80 degree 20lbs : 18.5lbs -There will always be tension loss due to friction inside grommet -greater the angle, greater friction loss -difference in friction loss found to be negligible at below ~45degree Autobrake may or may not affect the resultant tension depending on which angle the brake is engaged.
This is really interesting! I've been always wondering whether it's better to pull the string horizon to the cross string or to the grommet, but never thought about the way to measure the tension loss.
They call it crane scale. https://www.aliexpress.us/item/2255...lgo_pvid=3b5ae56b-b3f7-4e5a-8f3d-52508699b531
