National Hawaiian Cast Aluminium Lap Steel circa 1935/6

[Pickers Ditch]

I think I posted this in the wrong place so I've reposted it here.

I'm a bit of a naughty boy.
GAS got me and I bought this instead of the bass I was looking for.
Serial number N721 with its original G&S case.
I've sent the details to Mr. Makin to add to his lists.
The felt on the back has been replaced with some blue/grey polyester carpet tile type flock and I suspect the octagonal control knobs are replacements as they have little sign of use.
On the positive side, this is one beast of a guitar. Fabulous tone, bite and sustain that goes on for days.
The volume control is interesting in that it is switched at the full anticlockwise (off?) position. When clicked fully "off" it seems that the pick up signal bypasses the whole internal circuit giving an increase in volume and treble.
Can anyone give me any ideas of its age, history, background etc. please?
Has anyone on here owned it in the past?
Thanks, PD.

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[Brad Bechtel]

I haven't owned that particular guitar, but I have owned a similar model in my own past. I'd agree they have a fabulous tone, but I found two problems with mine:

1) The fret markers were mis-laid above the 12th fret by one fret, so the 15th fret marker was a fret 14, etc. Drove me nuts trying to play up high!

2) The guitar is very sensitive to temperature changes. I could get it completely in tune, take it out on stage, and the heat from the lighting would cause it to go way out of tune.

I sold it for those reasons, but they're great guitars otherwise.