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November 21 Tubing the Ampico-A drawerThe machine shop modifications to the cast aluminum transmission frame were successfully executed. It fits and works exactly as the original part.
A little Mill Wax restored the shine to the spoolbox and the drawer frame cleaned up nicely. A few of the removable bottom panels could use repainting but higher priorities prevail. Next, all restored pneumatics were assembled into the drawer. Some careful study and comparison was done between my disassembly sketches and the tubing diagrams I had obtained. This drawer was in original condition and almost completely intact. I was able to make a detailed sketch of all unbroken tubing connections before disassembling it. Between David Saul's 1925 drawer diagram and the popular Amphion tubing diagram, I was able to account for those few broken or missing tubes which were mostly on the bass end of the drawer. This, being a late 1926 type 8 drawer, did not exactly match either of the two diagrams mentioned above. The main difference is in how the reroll circuit components are connected. There is a 5/32 tee fitting with a .046" orifice installed but it is located in such a way as to delay the reroll signal from the tracker bar to the roll accelerator. I believe this is done to give the transmission time to shift into the reroll position before the air motor can begin to accelerate. The pump cutout is no longer teed to the accelerator. It is connected directly to the slide valve on the transmission shift lever. (see sketch provided)
Some additional study was done of my tubing sketches of the piano belly. There were more missing and broken tubes in this area and my sketches contained a number of question marks particularly in the area of the feedthrough blocks on each end of the primary chest. With the aid of the tubing diagrams and my hand sketches, I was able to account for 100% of the missing tube connections. My drawing of these feedthrough blocks has been included in the photo album.
After seeing a number of other Ampico-A restorations and hearing of peoples frustrations trying to replace lead tubing with rubber under the drawer, I decided to try something different. I designed and made a set of fanning strips which arrange the rubber tubing into two neat interleaved layers. The exact number of tubes in each of 4 areas was mapped and the space constraints determined. The Autocad layout proved everything would fit in the available space, so I proceeded to make the fanning strips out of 1/8" thick aluminum sheet. The photos illustrate what an astounding success this was. The main advantage is the ability to remove and replace a single tube if one should ever become obstructed or punctured during the useful life of the restoration.
At one point, I was looking into finding exact replacements for the equalizer springs. My search was unsuccessful and thanks to Noxon-7 metal polish, the original parts will now be usable.
Next, I will restore the take-up spool and do some actual spooling and alignment using a test pump.
Another trip to Keystone is penciled in sometime before Xmas.
November 08 Ampico perforator now producing Atlas rollsThe Mount Mansfield project has been complete for two weeks now. Both WVPS-FM and WEZF-FM are able to operate at full power from the new master antenna. Winter arrived early at the summit and some of the transmitting equipment had to be moved in the midst of a snowstorm. We kept four sets of tire chains on my truck and used it to shuttle up and down the 4.5 mile toll road until the conclusion of the project. There were issues encountered with the Harris transmitters which were reluctant to be turned back on after the move. Many parts had to be shipped overnight and replaced in order to maintain a full-power signal for Vermont Public Radio's scheduled annual fund drive. Upgrades to the intermediate power amplifier were installed. There were many issues with the aging WEZF transmitter as well. The exciter quit the moment it was turned off at the old location and several components in the high voltage power supply fell to pieces during the move. After a thorough inspection and refurbishing, we feel the equipment should have no trouble staying on the air through the winter. All of these repairs were not included in the original quote to relocate the equipment and we have been assured the extra expenses will be compensated. Many thanks to the WCAX-TV 3 transmitter staff; Ted Teffner, Harold, Fred Lavenberg and Russel Fraser, for their gourmet cooking, hospitality and assistance.
After returning home, progress resumed on the Chickering Ampico drawer components. Many brass and nickel plated items were restored using Noxon-7 metal polish. The original and replacement transmissions were disassembled. A cast aluminum transmission had been procured to replace the original pot metal transmission which was still intact but full of cracks and badly warped. The Noxon metal polish did a fine job putting a mirror finish on some of the badly oxidized brass gears (see photos). This replacement cast aluminum transmission seems to have some issues. It appears to have been used for some time in another piano but its dimensions do not exactly match my original transmission. The boss for the output shaft is 1/8" smaller in diameter and the location of the mounting holes is substantially different. In addition, a piece of the frame is broken off which is meant to hold one of the phenolic sprocket wheels in position on its shaft (see photo). I can fabricate a new sleeve for the undersize boss and machine the frame mounting holes to match the original spacing. I can also machine the frame to accept a new bracket for the sprocket wheel locator. Ebay buyers beware. I guess the ultimate solution will be to try and procure one of Bob Streicher's machined brass transmission frames and install the left-over gears into it. If a feeble attempt had been made to install the aluminum frame with its mismatched mounting holes, a serious roll tracking problem would have been encountered. The long drive shaft which couples the wind motor to the transmission needed to have new felt bushings installed into its mounting blocks.
On Oct. 29, I was able to make a trip to Keystone Music Rolls in Bethlehem where I stayed for a few days to setup the Ampico perforator for recutting Atlas 88 note rolls. I succeeded in making a run of 15 exact copies of Paul Manganaro's original roll; "Outside" pb Mabel Cowan. This is one of the best arrangements I've ever heard on an 88 Note roll! It is sure to be included in Keystone's next catalog. While there, a large lot of word stamping sheets arrived. Each sheet contains the lyrics for about 5 rolls. Our budding letter-turner Lulu Mae posed for the photo. Look for Keystones next catalog which will include a selection of word rolls coming soon!
While in Bethlehem, I visited John Zeiner & Sons to check on the progress of the 1926 Chickering. When I walked in, Mike was hard at work on rubbing out the finish of the main cabinet. The timing of this visit was good as I was able to take the finished drawer pieces with me. The photos only show the initial stages of the hand-rubbed finish. I didn't get a photo of the finished drawer pieces but they are amazing. Next, the plate will be installed and the pinblock drilled & reamed, then the new strings and finally the perfect striking point for the new hammers will be established. This should all occur during December. After five tunings and hammer voicing, I will bring my pianist daughter, Katy to do the final acceptance in late December or January. More updates to this blog will be posted as progress is made with the drawer, primary chest, pump, stack and expression regulators. |
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