Thumb groove

[SCWGuqin]

How does everyone here press down with the left-hand thumb? I know my own technique has changed over the years. For the past year (at least), I have been pressing about 50% flesh and 50% nail, along the "first half of the nail", between root and midpoint.

This works just fine, with one complication. I inevitably grind impressions into the nail this way, and as the nail grows the groove moves forward. That means each groove will last me only a few weeks to months, at which point it will have moved too far forward and I need to cut a new one. This process is inconvenient, not only because I need to toughen up a few millimeters of thumb that haven't been used for a while, but because I end up pressing down at a different angle that is somewhat less efficient. I'd say the 'optimum' placement for the groove is about 2 mm from the root.

Any thoughts on this?

[Charlie Huang]

I always use the exact 'mid-point' half-flesh-nail with no problems. Before, I used the near edge of the tip, and that created a groove (which slips off the string sometimes). Me using the mid-point now produces no groove at all. Either your angle is wrong or you're pressing down too hard (you would feel a tingling metallic sensation in either case).

[Si]

What do you mean half flesh half nail?

I dont think the string is supposed to touch the nail it is?

Should the thumb be bent at the joint so that it is not staight when you see it pressing on the strings?

[Charlie Huang]

It should be bent slightly to the left. And half flesh half nail means the body of the thumb is vertical and not slanted either way so the string touches both the nail and the flesh. Mei'an technique requires use of more flesh than nail, or no nail (meaning a slight slant towards the left).