Mechanical Music Digest  Gallery
You Are Not Logged In Login/Get New Account
Please Log In. Accounts are free!
Logged In users are granted additional features including a more current version of the Archives and a simplified process for submitting articles.
Home Archives Calendar Gallery Store Links Info
MMD > Gallery > Tech > vanceGage


Announcement: End-of-Year Fundraising Drive In Progress

Our End-Of-Year Fundraising drive is in progress. If you haven't contributed to the operation of the MMD in the last 12 months, this would be a great time to contribute. There's a PayPal link at the bottom of each page on the website.

If you aren't sure when you last contributed, please send me a note using the contact form at the bottom of this page and I'll look you up in my records.

Thank you for your generous support!
Jody

P.S. While your support is needed and appreciated, you do not need to contribute to be a subscriber. If you have subscribed and aren't receiving your Digest, please use the contact form at the bottom of the page and let me know. Thanks!

Manometer Vacuum Gage With Water Trap
Manometer Vacuum Gage With Water Trap
by Richard Vance (MMD 060123)

Since a rotary piano pump can suck 80 to 100 or more inches water column, with no flow, it is indeed impractical to make a manometer long enough to never be sucked out in any circumstances.  20 or 30 inches is enough for most player adjustments.

Making a water trap for a manometer is simple in concept; one just needs some sort of sealed chamber in the tube from the piano to the manometer, where the water will end up, if the manometer is sucked too hard.  The picture shows one way to do it.  The details are unimportant, as long as one keeps in mind some basic principals:

vanceGage.gif

The water must fall into the trap, rather than going all the way into the piano.  The chamber must hold all the water in the tube, with plenty to spare.  A 30" x 1/4" manometer holds less than two ounces of water.  But try it first to make sure the bottle is big enough!

Sucking out the manometer is bound to happen.  So it should be easy to unhitch the chamber; and lift it and tilt it so the water will run back into the tube when this happens.  When this occurs, some of the fluid will stick to the tubing and the bottle, and the manometer zero will end up 'lower' on the scale.  A sliding scale makes it easy to 're-zero' the reading when this happens.

Richard Vance
23 Jun 2001 13:50:09 -0400


24 June 2001

Home    Archives    Calendar    Gallery    Store    Links    Info   


Enter text below to search the MMD Website with Google
Loading



CONTACT FORM: Click HERE to write to the editor, or to post a message about Mechanical Musical Instruments to the MMD

Unless otherwise noted, all opinions are those of the individual authors and may not represent those of the editors. Compilation copyright 1995-2017 by Jody Kravitz.

Please read our Republication Policy before copying information from or creating links to this web site.

Click HERE to contact the webmaster regarding problems with the website.

Please support publication of the MMD by donating online

Pay via PayPal

No PayPal account required

                                     
Translate This Page

. .