Lindeman Player Piano
By Les Smith
With regards to the rebuilt Lindemen player problem, it would help to know what type of player action we're talking about, because they used at least 4 different actions-- Standard, Amphion, Pratt-Read and Angelus. Since you stated that it DOES have pneumatics, that eliminates Angelus (which used pouch pneumatics), so it probably is one of the other three. Do you know which one? Also, because of it's age, I assume that it has both primary and secondary valves. Correct? Before you post back to the list, there are a couple of very simple tests you can try that will help you isolate the problem. 1st check the lower bellows action. Disconnect all hoses and tubing leading to the pumping bellows and seal off their nipples with duct tape. A couple of stroke with the pedals should pull the reservoir(s) completely closed. How long will it (they) hold suction? 5, 10, 15, 20, 30 seconds? More? Can you hear any leaks? If so, have someone else pump the pedals and try to isolate the leak(s) using a stethoscope. Assuming that your rebuilt bellows are holding suc- tion for at least 30 seconds, reattach the hose(s) going to the stack and the one to the air motor. Put the transmission into "PLAY", the tempo at 0, and tape off the entire tracker bar with another piece of duct tape and start pumping. If you did a good job of rebuilding the valves and replacing the pouches the reservoir(s) should close just as quickly and hold suction just as long as they did before you attached the hoses to the stack and air motor. If they don't and if you can hear numerous leaks at this point, try to isolate them with the stethoscope. Most likely you'll find that the valves are not seating properly in the "off" position and therefor not holding suction. If you releathered the valves--top AND bottom-- the most likely cause of them not seating is that the pouches are holding them off their seats. This could be because the pouches don't have enough "dish" or because you used a lifter disk that was too thick. Remedies should be obvious. If, on the other hand, the valves DO hold suction at this point, remove the masking tape from the tracker bar and pump vigorously. While they probably won't all strike the strings hard enough to make them sound, all 88 hammers hammers should move to the strings. If they don't, it probably indicates that the valves are leaking at the TOP seats, or in the open position. The most common cause of this is TOO MUCH valve travel. The standard is 1/32", or, some- times 3/64". 1/16" is probably too much. As a final test, play a test roll that sounds the notes one at a time. When the notes play do they "spit" and can you hear them leaking? Once again this is a top seat problem, most probably related to too much valve travel, or not enough pouch movement. The remedies should be obvious. So run some tests and let us know the re- sults. BTW, after removing the duct tape from the tracker bar, clean the bar with some naptha to remove any traces of adhesive.
Les Smith
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(Message sent Tue 5 Dec 1995, 16:20:48 GMT, from time zone GMT-0500.) |
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