Here is not really a DIY kalimba of mine,
but rather an African-made one:
Made by Hukwe Zawose (R.I.P.), who was an outstanding East African musician.
This instrument is a very personal matter, as I was the bus driver for his tour
in Germany almost 25 years ago, and I paid him a visit in his home town in Tanzania in 1994
which was when he made this one for me.
The holes were burnt with an iron rod, the steel tongues are springs hammered flat,
and the resonating jingles , in the national colors of Tanzania were formerly food and drink cans.
Technically not nearly as perfect than your beautiful kalimbas, wooddrum,
but mine plays very well though, in tribal tuning of Mr. Zawose, not pentatonic
like many kalimbas, but rather like a C7/9 chord with all the notes in between.
P.S:: Here is a video clip about the Zawose family:
http://www.youtube.com/watch?v=2M7-_hFAEDYAs you can see, their kalimbas came in many sizes, and they have also been used therapeutically.