Questions about the KMC 1

[David Aubke]

This is a KMC 1 I'm working on for a customer. It's the first one I've seen in person and I have some questions.


1. Does the serial number really include the letter I or did they just use the I stamp instead of getting a "1"?


2. Any ideas as to the year? I can't find the standard manufacture date stamp on the harp.

3. How does the keyframe attach to the cabinet? I haven't even had the keys out yet but I'm guessing it's screwed down from the inside.
  Answer: four screws of the same sort that go in the front of the cheek block, down through the front of the keyframe. Four 1-1/2" oval-head screws down through the balance rail. And two of the same sort that attach wood harp supports to the action rail up from below at an angle through the back.

4. What's the deal with this capacitor and resistor (obscured in this photo) wired into the circuit?


5. There is no pin and screw assembly at the center of the damper release rail - the one that keeps the rail from bowing upwards. By the rail's appearance, one should be there unless someone knows otherwise.

6. Does the damper mechanism normally include a galvanized carriage bolt where the pitman dowel would be on a Stage piano? It works pretty well and fits perfectly, just looks a little rigged. Is that the way Suitcase pianos work as well?


More pictures at
http://www.shadetreekeys.com/kmc-1-10617/10617-photos/

[vanceinatlance]

I'll take a stab at some of your questions.

1. Yes the serial numbers on mine have I stamped on them. I believe it was a designation of the instructor model.

2a. On my 1972 model there is a date stamp underneath the harp on the pickup rail. I have an earlier one that is stamped in red ink on the top side.

3. The capacitor is a tap off the harp for a tape recorder that would normally be mounted under the right hand side of the keyboard.

For 4 and 5 I'll have to look at mine when I get back.
I just noticed looking through my pictures of my 72 model that my serial is I0610, so I would think it should be very simular to the one you are working on.
Hope it helps.
Just a curiosity of mine, but was there any masking tape with a number written on it attached to the harp of this unit,?
Vance

[David Aubke]

Thank you.

1. But my serial number says "I06I7". Two Is?

Why yes, the harp frame does indeed feature a piece of masking tape with a number. I'm away from it now but I think it was something like "302". Whatever could it mean?

[edit]You can just make out the tape and number in this photo.

[/edit]

[vanceinatlance]

I guess I should have wore my glasses. My serial number does include two I's or "I06I0". Maybe they used I instead of 1 as you suggested earlier? I have run across a unit stamped 4572 on the harp that has a serial with 1's on it "11219" I assume at this point they were using 1's again instead of the I's. So maybe this was done on the earlier ones only?
The carriage bolt is indeed on mine also. Seems to work very well.
I have no clue what the tape means, but I have seen it on the models with I's in their serial number including my earlier felt tipped model "I0I93" with a masking tape number of 883. I first thought possibly the school that had them did this until I saw this on units that were from other locations. I haven't seen this on any other model.

[Ben Bove]

Age would be 1970.  Turbo-Jet (TBJ) didn't start stamping dates on top of the pickup rails until 1971, and it may very well be on the underside of the harp - something like "March 1970."  The pickups are of the earlier design, with the bright red wire and the larger plastic housing found up to 1970.  The tonebars are also silver twisted rather than the gold plating which came about 1971.  Reason it's not a 1969 is because the lowest tonebars have the multiple bends to allow for the tine to swing up and not collide with the tonebar. 

I haven't determined the masking tape meaning, but my best guess forward is a quality control designation.  I've only seen a few numbers and they're always in the 300s, so wouldn't correlate to amp serial number or anything like that.  They're on standard silver top pianos of the era as well, late 60s.

They used letters in serials like "73B-0001" but having them in the actual digits is funny.

[David Aubke]

Thanks Ben!

I didn't think anyone knew what "TBJ" stood for. What more can you tell me about Turbo-Jet?

Do you think this originally had felt hammer tips. I'm pretty sure the square neoprenes on there now are replacements.

[Ben Bove]

Definitely would have had felt tips originally.  Almost all of them have been replaced and it's rare to find one with an original set!  They're usually grooved badly if so.

Tur-Bo Jet (I guess is the actual spelling), which also goes by "TBJ Designs" on its site, was a vendor that Fender used to outsource the pickups.  Just like the keys, Fender didn't make the Rhodes pickups in-house.  Looks like they're still in business, and still specialize in electro-mechanical devices including coils.

http://www.turbojetproducts.com/

[vanceinatlance]

Interesting info, thanks Ben! I had no idea the silver tops had the tape as well.

[Ben Bove]

I may actually have to think back on the silver top pianos with tape.  It may have been some Jetsons 60's pianos that I'm thinking of, which would be a student piano.  so I might hold off on confirming that until I find a pic.

[David Aubke]

Was a finish originally applied to the tone bar and pickup rails?

These look like they've never been finished - bare wood all around.

[Ben Bove]

I don't believe there was a finish applied.  Here's a similar age piano from 1970 that has the bare wood look.



I don't think they started applying finish to the wood until about mid 70s or so?  I recall plenty of say '72-era pianos with mold in the wood.

[David Aubke]

I'm considering replacing the T-molding that protects the edges of the cabinet wood.

Anyone know how much trouble I would have removing the old molding? I pulled on an inconspicuous section and it's in there pretty good. Is it glued? Will I destroy the channel pulling the old material out? Should I use a heat gun?

Years ago at one of my summer jobs, I spent a lot of time installing that stuff but I've never pulled it back out.

[The Real MC]

Check the bottom for nails where the two ends meet.

If no nails, then it was glued in place.  Yes you risk damaging the channel if you pull them.  A glue gun will melt the T-molding before melting the glue.

[Ben Bove]

If they are glued, perhaps there's a way to get in there with the right sized flat head screwdriver to pry it out

[laquer09]

3. The capacitor is a tap off the harp for a tape recorder that would normally be mounted under the right hand side of the keyboard.

Interesting.  I thought that was supposed to be a tape-in, the idea being that students could play along with lessons.  Are you saying this is actually an out, directly off the harp?  Implication being that I can take a raw harp signal and route it to my own pre-amp / amp...and then still have both the on-board amp/speaker as well as the line out available as options?  That might rule.

I'm a non-gigging musician, or at least not with my rhodes.  I am tinkering with production now, however, so the more personalities I can get out of my baby, the better.  Because it doesn't need to be mobile, playing around with options such as these is attractive.

Also - mine does have the original felt pads, and they are indeed deeply grooved.  Most people I talk to, including professional keys players (crazy how many sort of just don't care about what's under the hood, I come from a nerd guitar background), give me the "nah man, just leave it original."  I don't give their explanation a lot of weight since they usually don't have one beyond some stock answers you'd all expect.  However, this forum...I trust.  You guys and gals think it's a good move to replace them?  If so...with the neoprene pads mentioned earlier or are there better options? 

[Student Rhodes]

Were they tear drop hammers, I'd say sand them down.  However the cubes are pretty small, and are usually worn to about half the depth of the tip, and may be pretty hard after all these years.  You'll most likely want to replace with something.
I think Vintage Vibe, is now making replacement felt cubes for these pianos.
Keep in mind, the felt hammer/tip has a very different sound than the neoprene.  More "thunky".  I suppose part of the tonal assessment is also based on the Raymac tines that were used with the earlier felt hammered/tipped Rhodes.  If find them to be darker than later tines.

[pianotuner steveo]

And the felt cubes do not last nearly as long as the neoprene...

[laquer09]

Is the process for replacing them difficult? 

[David Aubke]

Is the process for replacing them difficult?

I've never replaced felt hammer tips but I can tell you that the most difficult part of replacing neoprene tips is removing the old glue. I clamp the hammer in a vise and use a file. I think this job would be dangerous (especially on early hammers which are often very brittle) and a major pain without first removing the hammers from the action rail.