A while back, someone wrote in that his TR6 had no pedal bushings. He
went down to King Bearing and walked away with some Garlock 10DU12
self-lubricating Teflon-lined bushings, installed them, and was happy.
I filed that factoid away, knowing that my pedal box was due to be
rebuilt soon. So this week, I also made a trip down there, ordered some
of the same bushings, brought them home, and found that they were too small.
This is a TR4A, not a TR6, so it's possible that the pedal assembly
changed. But I doubt it. The original bushing is a oil-impregrnated
sintered bronze sleeve, 3/4 od, 5/8 id, 1/2 depth. This is a fairly
thick wall. I suspect that the TR6 used the same part.
The Garlock bushings don't come with walls that thick; the bushing to
fit a 5/8 shaft is only .72" in OD.
Why did this work for the original correspondent? I suspect that,
having no bushings, the hole for the shaft filled with rust and
decreased the diameter. (I found a rather thick layer of rust in the
middle of my pedal, where the bushings don't meet.) The Garlock
bushings might well press into that. This might also account for the
fact that he had some trouble with alignment.
So, if you were thinking of making this same modification to your big
TR, save the effort.
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