So on first method you pulled both strings at same time? Now at some point you going to pull the other main for a second time. Is that ok? When you pull string twice doesn’t it stretch it and make it a little deader than the other main only pulled once?
I always use the second method you showed but think I might change to the first method using the addition of the starting clamp. This obviously is OK in the example you showed with a racquet that has a throat start and so the starting clamp is at the head end of the racquet but what about racquets that are the other way around and have a head start? Is there always enough room to place the starting clamp on the outside of the frame at the throat end of the racquet?
I use the second method. I mainly string badminton and squash racquets. However because the tension is only in the 22 - 28 lb tension range after pulling the first two strings and clamping l can keep the clamp raised by pulling on the string with my hand before the machine pulls again and is clamped so I don't have the dropping clamp issue. I guess that if I was to string tennis racquets on a regular basis I would consider using the first method demonstrated.
This demonstrates basically 2 ways, using different clamping techniques. From what I can tell, and I'm not a USRSA tech or anything, but my understanding is there are in fact 4 different ways, so 2 ways that you don't show. With the 3rd being a true double pull against the starting clamp on the outside of the racquet (anchoring on 1L main and pulling 1R main); and the 4th way also being a double pull, so similar idea but you anchor the 1L main against 2L main ON THE OUTSIDE OF THE RACQUET and then pull 1L, and then pull 1R (this would be like how you would start with floating clamps)... and then there's another channel here that uses a variation of that but instead of anchoring 1L against 2L on the outside with a starting clamp, he put the starting clamp on the inside against the grommet... which seems to make the stringing process easy but seem to me like it could damage the grommets.... However, I want to commend you for making a very clear and easy to follow video. A lot of what I've seen is full of rambling and people throw around terms inconsistently which makes it hard to learn.
I agree with what you describe as method 3 in your description. It's similar to method 1 in their video, except it saves a step (the tricky first pull he does with 2 strings in the tensioner). I don't see value in that 2 string pull. My method, simply pull by hand both strings at head of racket, start clamp outside at head, Double pull, anchor at at throat on same string that has start clamp, clamp final tension on adjacent string. Come back later and pull final tension on starting clamp, final clamp that string, and remove starting clamp before releasing tensioner brake. Actually, I guess there's some value, the tension in the actual span of the first anchor clamp (1 inch approximately) would be more accurate tension to final tension, that way, after coming back and pulling the starting clamp string to final tension, less slack comes out after unclamping first anchor clamp. Great video by the way. All methods are effective, but I agree, #1 is their best method.
When stringing the mains, why do we do 3 left strings and then 3 right strings? If both the left and right strings are at the top of the head, why not pull tension on both of them, then string them through to the bottom, then pull tension on them at the bottom, then string them up to the top, then pull tension on both of them at the top, etc.?
Method #1 is the Yusuki method. Nonetheless, In all 4 methods shown, you are not achieving full reference tension on the 2nd main string on the left half of the racquet. This is because, in all 4 methods, you are clamping (roughly 2 inches) away from the grommet/frame - therefore, the 1st left main, and the 2nd left main, will NOT be the same tension. The 1st left main, the 1st right main, and the 2nd right main are all getting full reference tension, but that 2nd left main is not. There is a way to completely avoid this, and prevent losing any tension on that 2nd main (regardless of which method).
Can you share the fix for avoiding the tension issue on the second left main? I have this same issue when I string on my machine. My fixed clamps are so bulky that I have to offset one from the other. I'm considering buying a new set of fixed clamps that have the adjustment knob recessed, but if there's a way to avoid that it would be all the better.
The Issue you mention can be avoided completely by using high quality Floating Clamps such as those manufactured by Stringway. Alternatively, much of the issue can be mitigated by pulling the 2nd main string to a slightly higher reference tension (5% to 10% more)
