Determining fingering for complex arpeggiations

Question

I've been drafting some composition work and created some arpeggiations in the LH to accompany the RH, but I don't want to start guessing the fingering, ironing in bad habits before asking about it, here's what I'm trying to play:

With the first bar I can cheat using two hands, but the others I'm having a lot of difficulty with, I've tried to work out the fingering for the first 2 of those, but I'm not sure if the technique I'm using is quite right, keeping in mind I'm trying to play this at around at least 60 bpm.

Would anyone have any recommendations as to what fingering to use for these arpeggios, or maybe a way to work them out for myself (Because sometimes when i've tried playing them i've ended up using fingers 1,2, and 3 exclusively and sometimes even just 1 and 3, which feels wrong)

EDIT:

For the second bar I'm now using 531312 521212

For the third: 532131 321231 (This one i'm having particular trouble with)

For the fourth: 532132 532132 532132 312312

The fifth: 321321 321321 321321 231231

The sixth: 532123

Do any of these clearly have a better alternative?

EDIT:

After a few hours practise I can pretty much play the whole thing...except bar 3 with the notes Eb G A C Eb A going up then down to that lower Eb and repeat - Will continue trying this bar for a while longer, (It's just I don't want to use techniques that enforce bad habits)

Answer 1

With 6 notes and 5 fingers, you obviously need one hand position change in each sextuplet.

Work systematically through every possibility of where to use your thumb in the middle of each group, then find the best way to finger the other notes around that thumb position.

The "best" fingering for you will depend on the size of your hand and your playing ability. For example some people might find 543212 is "best" for bar 2, while others might find that fingering almost impossible at your tempo.

Some of the groups are straightforward major / minor / dominant 7th chords, so using the standard fingering for those arpeggios is likely to be a good idea.

Answer 2

If you can sacrifice the length of the chords, you can divide the work between the hands:

L5345 R12

If you wish to keep the separation between the hands, a more natural way - that sacrifices the 1/4th legato phrasing - is to simply move your left hand:

L531 L531

This is a fluid playing style, which could even be extended to crossing clockwise over the thumb from 1 to 5 for a legato if the next key is only 1 or 2 seconds away. From a composers viewpoint, the additional stress (due to the extra phrasing) does align with the intentions of the right hand in the third bar.

I hope this helps!

_{Rachmaninoff wrote impossible segments, not only owing to his huge hands, but to the fact that the passages required swift jumps to simulate a single huge chord. However, writing with playability in mind can help you spread your music.}