DIYAPASON-L Digest #417 - Wednesday, October 24, 2001
 
Re: Spencer blower, Century motor
  by "Jon Fick" <jon@VermontFicks.org>
Re: Spencer blower, Century motor
  by <TheGluePot@aol.com>
Re: [Residence Organs]  Re: Spencer blower, Century motor
  by <GRSCoLVR@aol.com>
 

(back) Subject: Re: Spencer blower, Century motor From: "Jon Fick" <jon@VermontFicks.org> Date: Wed, 24 Oct 2001 16:11:44 -0400   I think all of these points are valid and offered in the best light. And that's the way I take them, for sure. I've been thankful for Diyapason-L and it's members as I undertook the restoration and installation of this church organ.   Al, I do indeed need to put a belt guard in place. I'll bend something = up, one that won't resonate.   I decided to keep the old Century motor. When I get a spare week one day I'll disassemble it, clean, adjust according to the manual, and test it, = and then store it in the corner. It could easily be reinstalled someday. = (I'd like to, actually.) If I discern that the Century had some definite = issues and is now reliable, I'd consider reinstalling it. It runs all day andhardly gets warm. Once it's up to speed it's an exceedingly quiet = motor, (insert other good points here.)   I installed a 3/4HP motor rather than 1/2HP to compensate for losses due = to rolling friction of the belt. I also hope it will sort of loafe along as well. The motor has bearings specifically due to the side loading that is encountered. They are not oil-impregnated bushings.   I had considered leaving the Century in place and installing a pulley on it's tailshaft with a belt to a new motor. This was suggested by John V. It would probably have worked just fine. The Century would have been a giant pillow block, in a sense. An axially-mounted, Lovejoy-coupled motor would have worked fine as well. I just didn't have any room beyond the tailshaft.   It's not a capacitor-start motor. It does start OK, taking as long to = start as if it was in a furnace blower application so I didn't think it an undue time. I did notice, however, that it's drawing 40 amps for a second or = two. The 20 amp breaker seems to hold. If the Century had been left in place, the startup rate and current surge would have been far worse.   I avoided a spring loaded, hinged system right off. I may well have to = add it.   Fixing fatigued axial springs in the centrifugal system requires parts = that are not made anymore and would require some scrounging and some time. = Time I didn't have. I don't think this is necessarily a "better" solution than the original motor, nor is it the only solution as several have pointed = out. It's just a good solution for us at this time.   The whole reason for my efforts was to avoid frustrating organists and = music committee for the time being. So, I gave the Century a good college try, and upon failure did what was expedient. That's what we engineers always have to do. (By the way, you can always tell an engineer, but you can't tell him much!)   I hope it doesn't catestrophically fail someday. I think the Elder's wouldn't have any difficulty if I added crashing cymbals to the organ, but they might balk at crashing fans!   I appreciate the discussion.   Jon Fick      
(back) Subject: Re: Spencer blower, Century motor From: <TheGluePot@aol.com> Date: Wed, 24 Oct 2001 17:02:36 EDT   Jon:   As a good engineer you have covered all of the bases and your very well = built and designed motor mount should work flawlessly. The key is that you will = be there to check on the belt regularly.   My concern was from experience in taking over a retired organ mans = contracts where he put belted motors on most of the blowers so they could run off of =   what currents were available from local power companies (3 phase not available, etc.). He made a good living just keeping his belt drives = going at each church. Now I have them but the farthest away is some 90 miles = and it failed regularly (2HP) until I mounted the drive motor in-line with the =   shaft via a coupler. With gas prices what they are today in California I = was losing money with each call so one by one the belts are going. My biggest =   challenge is a 5HP blower that burns a belt a month. It is a monster with = an old gutted DC motor but only enough room on the shaft stub (hacksawed off) =   for a single belt pulley.   Best wishes,   Al  
(back) Subject: Re: [Residence Organs] Re: Spencer blower, Century motor From: <GRSCoLVR@aol.com> Date: Wed, 24 Oct 2001 17:59:20 EDT   Jon--- I beg to differ with you on the inrush and starting current on the Century =   motors. These motors were built in the age when "adequate" excess = electrical capabilities did not exist outside the core sections of cities. Therefore = the Century repulsion start , induction run motor was quite satisfactory. I = have never had one of them draw huge amounts of current at startup. = However,,,its a moot point, you have replaced and are up and running. Cheers, ---Roc L V Rockafellow Niew Joisey