Anti-slip guqin pegs data - ongoing update

22Aug2016:: data from around the world, diff climate, diff temp, diff humidity all mixed

Test: Is "slipping" a common problem? and if using old pegs, how much slipping happens in a 2 to 3 hrs or more period?  
What might be the condition that makes "slipping" happen?

I noticed under very hot stage lights, the silk strings are often affected by the heat, and i see master players adjust their strings every now and then before playing a piece.

If under normal conditions, there is no slipping, but under performance conditions, due to heat from the lights, this happens, would "anti-slip" pegs be of great help?

Here, under high heat, the strings themselves stretches more, so, the problem of slipping notes is not in the pegs but more in the adjustment of strings

Therefore, the anti slip pegs are useful for ... regular conditions.  Its always helpful to have a locking device to minimise slipping of tuning.  Always gd to have more control.

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More discoveries thanks to input of all feedbacks
Conclusion 24aug2016:
I have thought about this question for the last few days. In fact, the traditional pegs work fine. Its just that to fine tune, if you use a screw mechanism its v smooth turning. And thats about it. Still smooth turning is better than non-smooth turning. All pegs should be anti-slip either by friction or by mechanical device (screw). Thanks for your feedback.

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1  CE(uk)/ 22aug2016
old traditional qin pegs, str#1, no change after 2.75hr  //  

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2 JYST (Canada)/ 22aug 2016
old system once tuned, stays at least one wk no need to retune. // maybe due to qin and not only the pegs

Of course not, too poor

Also, as someone who uses original parts from shop, and able to fix own stringing, why would I?

But I can tell you my pegs don't slip

Provided they are not moved and laid flat on a table, I find that I can leave a qin alone for a week and it's the same after

Not every qin can do this, of course

But mine is OK indefinitely, I haven't tried leaving one on a table long enough to be untouched

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3  YH (NY) /22aug2016  Adjustment every day. Dryness due to heating in winter also affects. Only very occasionally, I don't need any adjustment. It's because of silk strings and not because of pegs, I suppose.
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4  JB (Portland) / 23aug2016

I always adjust the tuning before I play anything in a session and will check it into a session after a bit. If the weather is not stable strings may stretch or tighten. I'm not sure what anti-slip means. anti-slip technology so called means the peg pool is sanded roughly and should not be smooth. The top of the pegs are concave (this is traditional and is mentioned in the yuguzhai). one can always roughly sand the top of the peg as well. Simpler first things to try are to apply something abrasive to the peg pool like chalk dust or the like. Or candle wax if the peg is too tight. New strings always stretch and it isn't unusual to have to put silk strings on/off in toto 3 times if they are new. n-m don't usually need a restringing but they still stretch when new. Sometimes slippage may be due to the rongkou themselves and the usual fault is that the last twist over the top either wasn't done or needs to be done one more time.

Why or why not? Do you think w screws is better?

Irrelevant for n-m strings. Useful for silk strings since you need to detune 6-7 or 5-7 every time you stop playing and restringing gets old fast and the strings being organic tend to move more. Also that was a joke. But the cost needs to come down.

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5  HY (hk) / 22aug2016

The simple is the best

For new silk string, re-stringing twice it becomes stable. It usually lasts for over a month.

Slipping of silk is due to incorrect fixing the silk on the leg

Traditional one is good enough

Tiny adjustment is required due to variation of humidity

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6  TW hk:

 I did experiment on the guqin pegs as you suggested. A newly stringed guqin may not hold on for a time longer than 10 minutes (assuming that the strings are being played) if the strings are new. Strings no. 1, 2, 3 give way relatively easy. If the strings were more or less settled down, the pegs may stay tune for days. They work better with steel/nylon and composite strings. Silk strings, by their very nature, loosens relatively fast.....
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