Very important maintenance item: Bus Bar Shifting

[Tonewheel]

Not wanting to hijack a very interesting thread on Busbars between PGR and Bobman, this is a new thread in which I wonder if we should all take heed to Bob's (Bobman) quote (emphasis added):

IMO, this is going to be the demise of many of our cherished Hammonds. The Buss Bars are a part that has no alternative available other than to harvest from a donor.
These parts are also subject to wear.

I would recommend to all reading this to look into cleaning your buss bars, and to give them a little shift every few years to spread the wear points. This will help them last longer.
Damage as is seen in the above pictures are a result of constant wear in a single spot done over the life of the organ.

I was hoping that others would chime in on this video below, asking how often this should be done, and are there any warnings about this procedure (power off, unplugged, all presets cancelled, etc).

https://www.youtube.com/watch?v=M-hsogXIX2I

[geoelectro]

This is of course true. I shift busbars all the time. My motivation may differ from a home user since I work on really worn models being heavily used.

All busbars start in the factory position, full CW. (clockwise) A full single tun CCW will slightly move the bar to a new location. Under normal playing conditions this should be done around every three to five years. You will eventually run out of turns after around 10. If you start to see intermittent contacts it should be done then. If shifting doesn't help, then a cleaning is in order. I still run into organs with the busbars in the factory position that seems have never been shifted. Even the -2 series.

To shift, release the presets, shift, then re-engage. You may need to run the keyboard a few times before the contacts work best. Same with the presets. They should be exercised as well. There is no need to unplug or even turn it off.

Geo

[Tonewheel]

Thanks, Geo.

Al of this is very helpful.

Dave

[stefanv]

Can/should the busbars be shifted in the M-100 series? Also, how much playing is "normal playing conditions"?

[geoelectro]

Shifting in the M-100 uses a different mechanism making it hard to make incremental changes. Still, shifting extends the life of the busbars. BTW many M-100's use the brass round bars. Once they start giving trouble shifting usually doesn't help. This is because the bars are tarnished. Cleaning will make them like new.

It's hard to qualify home playing against professional or institutional (gospel church) playing but suffice to say home playing is usually not as often and not as hard as pro/inst. We all know playing the keys harder or softer makes no difference to the sound. However, many pro/inst players hit the keys really hard because of emotion and performance etc. Hitting the keys hard does accelerate the busbar wear.

Geo