Flexible Fingering Patterns

To reestablish basic finger flexibility, accuracy, and patterns, begin and end each practice day with scales and chords in every key throughout the keyboard and use the three fingering patterns, those based on finger 2, on finger 3 and finger 4.

During the practice day, when working on current and new music projects, you notice that the scale used in various musical sections shifts, usually to a related key based on the Circle of Fifths.

You notice that you are playing a scale pattern but the basic pattern is now based on a different finger.  For example, you start playing the first section using a scale pattern based on finger 2. In the next section the scale and chords shift to a related key with a pattern based on finger 4.

So rather than always shifting your fingers to play scales based on finger 2, by playing scales equally well based on fingers 2, 3, and 4, you don't have to move your hand position, which helps playing accuracy.

Finger and Mental Flexibility Exercise

On a C major scale, start on G with finger 3 and play down to C and back up to G. (Notice that the C was played with finger 2.) 

Using the same major scale, start on G with finger 4 and play down to C and back up to G. (Notice that the C was played with finger 3.) 

Using the same major scale, start on G with finger 2 and play down to C and back up to G. (Notice that the C was played with finger 4.) 

Now mix up the patterns by playing alternate buttons on half of the pattern. For example, start with finger 3 on G and end with finger 4 on C. Then shift the finger 4 on C to finger 3. Start playing the pattern upwards and half way up shift to alternate buttons and end on G with finger 2. Mix the pattern up into its various combinations.

For practice, work out various fingerings on Irish jigs and reels. 

http://www.irishtune.info/session/tunes.php

http://www.novasession.org/sheetmusic.html#.Uyj8yPldVyJ

http://www.thegrotonsession.com/tuneindex.html

Fingering Patterns for Chromatic Accordion

Searching the internet confirms this idea of combining fingering patterns.

http://en.wikipedia.org/wiki/Chromatic_button_accordion 

Types of Fingering

On the left hand, use finger 3 as the basis for the scale.

http://en.wikibooks.org/wiki/Accordion/Left_hand/Lesson_4 

Robert Smith, although for piano accordion, explores the variety of fingering styles that you can adapt to your practice.

http://www.ksanti.net/free-reed/reviews/smith-rl_fingering.html

Eric Butterworth has amassed a resource for Bulgarian folk accordion music. He recommends fingering based on fingers 1 (thumb), 2 and 3. His fingering drills are an excellent resource to adapt to your current fingering practice.

http://www.goldov.com/butterw/emdb/

http://www.goldov.com/butterw/emdb/tutorial.html

Sandra Milosevic plays Serbian and Bulgarian folk music on piano accordion using primarily fingers 1, 2, and 3.

https://www.youtube.com/watch?v=wJ8Vr9bs8ag&list=RDr72harldNuU 

However, for chromatic button accordion, use fingers 2, 3, and 4, as shown in the link below by Danijela Predic.

https://www.youtube.com/watch?v=RyIHsDOANY8

Super Mario Theme on CBA

How about some chordal playing? The left hand is in Free Bass mode, playing single notes on all buttons. This feature is not commonly available.

https://www.youtube.com/watch?feature=player_embedded&v=GI2a7_XfKaI