Picked up a pair of chrome Bertoia side chairs last week, I bought them last minute on ebay so I didnt have the time to investigate them fully
The construction of the chairs seems very good I have compared one of the pair to my single white side chair (which I believe to be genuine Knoll)
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However the main body of the chair is a slightly different shape with the white chair having a more sloping base and less upright back,
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also the backrest of the chrome chair is approximately 1 higher than the white
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Another major difference is on the edge of the base as the pic shows the white chairs vertical wires run underneath the leading edge whereas the chromes run on top
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The bolts on both chairs are the same and appear to be in imperial size
The guy who I bought the chairs off mentioned that he had owned them for some time
Was the design ever modified at all? Could the chrome model be an early version or I am just clutching at straws :--(
opinion
My opinion (I have studied these heavily) would be that the white one has a dislocated base upright (maybe rewelded), as the vertical bars, (that rise from the floor, and weld on to the upper frame work) have allowed the seat basket to settle lower than the chrome one. My picture archive indicates that both are probably knoll, though the early Knoll versions have a double perimeter wire (which is both over and under the internal wires) and then, smaller diameter wire, that broke/bent easier. The wire tucking under was probably a production variation sometime, that went away after a while.
Neither are worth more than 75-100 so its not like there is a fortune here. Though maybe Knoll will be worth more someday. I think these are very common, and probably even made before the reproduction guys started.
I have pictures of the very earliest ones, own plastic shell versions, 60s versions, and 90s versions. Personally, I like the 90s to current versions as they are heavy duty, and more suited to letting huge people plop into. The old ones bent and broke if you worked them hard.
Don
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