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From: Mechanical Music Digest, 980924 MMDigest Date: Thu, 24 Sep 1998 17:36:36 +0100

Subject: Removing Rubber Tube from Brass Nipples

It's not until someone says, "Well, I never thought of that!", that you realise that maybe you do have a tip to pass on.

Getting the old grey rubber tubing off brass nipples is a real pain, as more often than not, its welded itself on.

So, arm yourself with a medium soldering iron with a bit the size of the nipple aperture, insert it for a few seconds, take it out, and, use a pair of small pliers behind the sleeve of rubber, lever the sleeve off. It will come away smoothly and cleanly.

Once you develop the rhythm of heating one, whilst you're removing the previous one, you can clear a stack in 10 minutes.

Best wishes to all

Nigel Perry

This article was written by Nigel Perry, contributing author for the Mechanical Music Digest


Question

I bought a 1924 Wurlitzer player piano for a project.When playing a roll I noticed that some of the notes were not being played. Incidently, an electrical vacuum pump was added. I removed the whole stack and looking at the back I noticed a piece of electrical tape was partially covering a series of holes (88 to be exact) that were between the two rows of pneumatics. Thinking this was the problem, I covered them with new tape and put the vacuum pump on it. That was not the solution. I removed the tape and covered the tracker bar with tape Still, when I slowly removed the tape most of the keys never moved.
All the pneumatics look new to me. And also, they didn't have black electrical tape in 1924............ Can you help me???

Answer

There are a number of things that can be checked to determine why selected notes don't play. You'll need a test roll, a listening tube and a tracker bar pump.
Isolate the notes that don't work, one at a time by covering the tracker bar with masking or scotch tape. Then put the listening tube up up to the open hole. It should have a distinct hissing sound indicating there is good bleed. If you're not sure what a good bleed sounds like, uncover a working note and listen to it first for comparisons sake. If it's not strong, clean out the hole with the tracker bar pump. Try it again. If it seems like there is excessive bleed (hissing loudly), there is a hole on the note pouch and the stack will have to be dismantled and the pouch replaced.
Notes that don't play (when the majority do play) are typically related to either excessive dust in the signal line or the pouch. Occasionally, the problem is the valve itself. You can also isolate the non-working note, put a suck tube (just a piece of small rubber tubing) up to the note hole and suck and blow on the tube. You should be able to 'feel' the action of the pouch puffing in and out. If you do have to open the windchest, check to see that the effected valve can be moved up and down easily.


Musically,
John A. Tuttle


From: "kvinen"
Subject: Stump the experts - maybe!
Date: Fri, 28 Mar 97 17:02:50 PST
Hi John - I just finished (are they ever finished) a rebuild of a Very Early Bush & Lane upright with a Welte system. Found a lot of pencil dates for 1912 so it is early.
Do Weltes sound like a recordo with an attitude? Mine does! It has the ability to play the softest passages and the Loudest passages, but the MOOD SWINGS are just not natural. Perhaps I am spoiled by my Knabe Ampico "B" grand!
I have done everything by the book and triple checked all the settings and adjustments, but it still does not sound right to me.
Any tips? I must mention, this one is so old it does not have knife valves, but rather flap valves.
While I'm on line I might as well do two for the price of one.
I have a super little spinet Ampico with an "alligator" pump. It's noisy as hell. Mr. Ampico, Bruce Clark says to put the pump in the garage and bury a suction line into the house to remote the problem. Have you ever had to deal with one of these creatures and if so, how did you get rid of the noise.
Kind regards and happy easter - KEN
--------------------------------------------------------------------
Hi Ken,
It almost sounds like a tubing problem. After I finish a reproducing mechanism, I always put it through a FULL bench test before installing it in the piano. It's extra work but it makes testing the vacuum levels for each graduation much easier. Then you are assured that the mechanism is not the problem. Some of the older Welte expression mechanisms did not follow the book. I've worked on two that had the valve boxes "out of order" from the book and it drove me bonkers. Finally, I took it back out and put it on the bench and played with the combinations of valving until I figured out the correct tubing from the tracker bar to the device. It's times like these that really test your understanding of the principles of operation to the max.
Some obvious questions might be, are the crescendos reacting correctly in terms of time? If they are off by even a second, they will have a pronounced effect on the overall performance. Is there any cross-leakage between the bass and treble in the stack? They must be 100% independent. With the same vacuum level applied to each side of the stack, is the actual vacuum level identical at the valve nipple? Since the volume level of the piano is subjective (from note 1 to note 88) the only thing you can rely on is the vacuum levels as measured at the stack. When I calibrate the mechanism, I use three gauges. Two on the stack and one at the rotary pump.
There is one area that requires special attention and that is the spring tension in the expression block that controls the forzando and the springs in the forzando off-pouch on each expression regulator. I use a finely calibrated set of weights to test these springs. Since the majority of the adjustments are related to time and vacuum level, it is imperative that the air motor and governor work perfectly. In closing, I actually find the Welte mechanism more life-like than either the Ampico or the Duo-Art but that is a personal preference.
--------------------------------------------------------------------
Date: Sat, 29 Mar 97 14:29:13 UT
From: "Craig Brougher"
Message-Id:
To: "John A. Tuttle"
Subject: RE: Welte Problems
Ken was asking about a Welte:
>Do Weltes sound like a recordo with an attitude? Mine does! It has the >ability to play the softest passages and the Loudest passages, but the >MOOD SWINGS are just not natural. Perhaps I am spoiled by my Knabe >Ampico "B" grand!
When asked if early models of reproducers sounded less than real, I always have to remind people that it was these models that created the market, that went onstage, that toured the country, and that were hyped by famous artists till they were blue in the face!
I have given Durrell Armstrong at PPCo a one-page description explaining the CORRECT way to regulate the Welte with its test roll. Have him send you a copy. Sounds like just a regulation problem if everything else has been correctly restored.
>I have done everything by the book and triple checked all the settings and >adjustments, but it still does not sound right to me.
That's the problem. No welte that has ever been done by the book is any good! That's why I had to write my own technique, after studying the system. They take a LOT of fussing with to be any good. Their technique is a "back-and forth" system of adjustment. The adjustments interact. Also, your packed bleeds (if it has them) may be too tight, so if you notice certain bleed adjustments having little effect, that may be the cause, too. Timing is critical.
>Any tips? I must mention, this one is so old it does not have knife >valves, but rather flap valves.
No matter. It is self-compensating anyway, so as soon as the pressure in the stack gets to a certain level regulated by the spring, the flap begins to close, or at least to regulate at that level. Just like the Ampico.
>While I'm on line I might as well do two for the price of one.
> >I have a super little spinet Ampico with an "alligator" pump. It's noisy as >hell. Mr. Ampico, Bruce Clark says to put the pump in the garage and >bury a suction line into the house to remote the problem. Have you ever >had to deal with one of these creatures and if so, how did you get rid of >the noise.
Funny. I've done a number of those pumps and have had great luck with them. I call them "grasshopper" pumps. Little bitty fellows. The problem with most "rebuilds" (if you will allow the term) is that the flaps and seats are never replaced.
If a pump is anything, it is no better than its valves. Half the time, the leather on the inside seats are so dry-rotted they can be zipped off with a putty knife. Also, flap springs have to be stretched at least 1/8". And when flaps are replaced with garment leather, garment leather stretches, so very soon, there is no more spring tension and the pump knocks
Another problem is the cloth used. On those little pumps, the best covers would be the thin pump cloth that Schaff sells. Then you have to put cabretta punchings on the in and out folds of each bellows to protect them from wear. Do not use lambskin. Use cabretta-- only.
The original grease for the rods cannot any longer be found. It was long fiber wheel packing grease with graphite-- for model T Fords. Today, I use JAX. It is the world's dirtiest, stickiest, awful-est stuff and to make matters worse, it comes in a spray can. But, boy does that stuff solve the problem of fiber or wood bushings around a steel crank rod.
Finally, the wood bushings will wear out a crank if they are not lubed right, Then they won't fit and will thump. Do not fold the cloth with a front flat fold. Modern-day cloth will not stand up to that. It will shred out on the sides.
The last thing I can think of is the mounting, which can creak itself, and if it allows the pump to move, the pump itself will thump. Anything that causes the pump pulley wheel to slow down and speed up while going around-- be it a drop in loading or a change in position, will cause the pump to thump.
Craig Brougher


Subject: Good Hammers
By far and away, the most trouble proof hammers are Abel Hammers (German) available from Wally Brooks.
Old Lyme, CT
800-326-2440
Subject: Folding Bellows Corners
Player Piano Company in their catalog recommends the best crease in bellows is _no crease_ at all:
"If the cotton pneumatic cloth is never creased, but instead allowed to fold naturally by vacuum under a situation where the pneumatic is prevented from closing by 1/8", the wear life will be increased by three times.
Most player manufacturers placed a felt punching inside the pneumatic, just behind the fold, to prevent the hard crease. A few makers did not do this, and the result was pinholes and slits on the folds after about ten year's use."

Need Service or Parts for the Pianocorder System?

As for service, the Player Technicians Listing is the best I can offer. If a technician says he/she works on ALL types of players, it's a good bet they will work on a Pianocorder system. However, I don't know of any technicians (myself included) who actually repair the individual circuit boards.

As for parts, the gentleman who does the actual repairs and/or supplies replacement boards and/or components is:

Bob Baker
Electric Orchestras, Inc.
29962 N. Terre Drive
Libertyville, Il.
60048
(847) 367-7996

Last Revised on March 9, 2002 by John A. Tuttle
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