Rebuilding a B3 manual/keyboard and the order of disassembly. Please advise.

[jhelm_waterw]

Hi again all and welcome to my current project.

To make a short story interminably long...
I scored a very dirty complete set of manuals from a B3 (both keyboards, drawbars, perc switches, chorus select box, preset panel and mixing transformer)
Whoever removed it from the original organ just cut the TG loom, chorus loom and power loom (no biggie).
I have no history as to why it was removed. (was this a bad set of manuals or were these working and someone remove them from a unit with a bad TG? I don't know)

As such, I cannot trust much of anything on these keyboards and thus need to go over them completely before risking soldering 91 connections to find they have contact, bussbar or resistor wire problems.

I have already
a) disconnected all Preset wiring from preset connector panel
b) split the two keyboards from each other (cut all the parallel black loom wires between the two.
c) removed all the keys
d) removed the manual endblocks
e) removed the front black faceplate

I FULLY intended to
a) remove the bussbars and clean them using procedures detailed in other threads
b) replace felts
c) fix anything else I find

So now I have a nice bare key assembly. (see pic)

I FOUND (after dissasembly)
a) there was a LOT of dirt and crap under the keybed (cleaned up easily)
b) there is some dormant surface rust under keybed (not that bad, probably spilled beer)
c) upper manual had a crack in the phenolic solder terminal strip (underneath where TG wires connect to resistor wires) (fixed that with epoxy, no problem)
d) the felts actually seem very good
e) no signs of any real water or smoke damage
f) I pulled one bussbar and I could feel some contact pits but the bussbar was rather shiny and seemed to be in overall good shape (flat bussbar, not round)

I am guessing I should gain access to the BACK of the key contact area so I can
go through EVERY DAMN key contact 1 by 1 and ohm out for continuity ?

So... where should I take it from here?
Should I try to dissasmble more and get into the key contact area?
How do I do that? (What is the next peice to remove?)
I'm trying to be patient here and not just start removing every screw I can find.

Any suggestions would be appreciated.

Thanks in advance

[Brendon Wright]

I probably wouldn't bother going in there myself, just once I had the thing connected doing the ear test on each contact...

I've only disassembled a T-500 manual loom, but as far as I recall there ought to be a whole row of hex screws along the top of the metal box, it should be pretty apparent how to get in. The top ought to come off after the screws are out.
In the T-500 there was nothing that would fall out by undoing the wrong screws...

[jhelm_waterw]

In the T-500 there was nothing that would fall out by undoing the wrong screws...

Yes... that is exactly my fear. That "SPROING" moment when you dissamble something in the wrong order and sh*t goes flying everywhere.
That is a heart sinking moment (and yes... I've done that before)
Hammond being a watch maker, I expect more sproing than there is.

I just removed the long cap atop the contact assembly (through which the reed pushers stick out).
The inside of the contact box/compartment was remarkably clean.
Hammond did an EXCELLENT design job on that peice such that all the reed pushers (what are they really called?) are raised and gasketed above the
base plate surface such that any spilled liquid will drain AWAY from the contact compartment and not funnel INTO it.

What happens if I remove the Key mounting bar from the top rear? (see the pic)
keyboard1.JPG
It seems to be the "backbone" of the entire assembly and it covers the rear of the contact area.
I am concerned the entire assembly will flop, twist and torque all over if I remove it.

[Brendon Wright]

Ah found a pic of my one. Yep, that bit has to come off. I'll show you a photo in a moment....

[Brendon Wright]

Here 'tis.
See that piece does indeed get removed, and while my manual loom is a ton smaller than yours it DOES face the same way 'round after all:

[jhelm_waterw]

Hmm, those reed pusher things... key actuator sounds pretty good!
Oh, a better question. Have you got the SERVICE manual? That'll explain a few key things, hopefully

Brendon, thanks SO much for that link. I did not have THAT service manual.
The service manual I printed and reviewed a few nights ago did not get in as much detail.

I just came in from the garage. I went ahead and removed that main keymount "strut" bar from the assembly and everything opened up nicely.

I'll post a pic tomorrow. This is what I know at this time...
"I hope to hell I never have to monkey with the contacts and resistor wires"
Wow... what a freakin nightmare. I just cannot even imagine assembly line workers doing all this manual work.
One hammond must have been THOUSANDS of man hours (they must have had an automated test jig to QA these manuals)

Using the charts in the manual, I'm going to walk through every contact.
I'll have these manuals perfect in no time.
Good timeing... I just scored a newer 91 tone TG.
I smell Frankenhammond...

I'll keep you apprised of how it goes.

Thanks for the advice.

[Brendon Wright]

Hmm, those reed pusher things... key actuator sounds pretty good!
This box is a bit bigger'n my T500's one of course...
I can't answer the next Q unless I see the back, under the key mounts.
The T series keys seem to be accessed from the opposite direction from this, if I remember aright.

Oh, a better question. Have you got the SERVICE manual? That'll explain a few key things, hopefully:
http://www.archive.org/details/Hammo...iesB3A-100RtDG

[Brendon Wright]

I guess we still don't know what a brand new analogue Hammond would be worth today....