Bevel Gears – Wear and Bushings

Bheem removed the the bevel gears connecting the four faces. The top gear shows considerable amount of wear. The edges have become sharp as evident from the pictures. His initial plan was to exchange the top bevel gear with the lower one which has much less wear. This didn’t work out as the two gears had different mounting holes. The pics are already in the drive folder.    After showing the gears to Prof. Sangwan the gear were put back next day. He was also saying the bushings on the faces have worn out too which need to be replaced after convocation.Bottom gear 2 Bottom gear 1 Top gear 1 Top gear 2

Face and Bell Check

Face Work

  1. Decoupled the bevels at the center by lifting the vertical bevel and supporting it on a small block
  2. Rotated the individual faces (Pankaj made note of the resistance faced)
  3. Noticed that SR face was balanced such that the minute hand returned to the horizontal position no matter where it was let go.
  4. Play in the shaft
  5. Bearing appears to be the same type as in the bell hammer set up.
  6. Set the faces at 12.02 pm and left them to see when the clock stopped again.
  7. The clock had slowed by 1.15 and was lagging behind (showing 1.10)

Bell work
1. Inner casing(white) of the control cable coming out with the inner metal cable at the gong machinery end.
2. Kink in the control cable may be causing some disturbance in smooth operation.
3. Hammer was badly in need of lubrication
4. Lubricated the bell bearings and the control cable at the bell end
5. Need to get crimps(or the cycle thing -forget the name) to seal the ends of the control cable and    maybe a rubber cover to prevent shit from getting in
6. Need a walkie talkie app for communication from the bell chamber to the machinery room

Another Tower Comes To Life!

kasauli-christ-churchGather around children, and let me tell you a tale. I’m a pretty old tower you see, and I have many a story to tell. But today, I’m going to tell you a story of my older and smaller brother. He’s been silent for the last 20 years, but has just started singing again! Don’t let his size fool you, the Christ Church Tower in Kasauli has been around since 1863, and he’s a magnificently built fellow…

 

Ashwani with the gear trains of the Kasauli Clock  Tower.

Ashwani with the gear trains of the Kasauli Clock Tower.

We clock-keepers are a connected lot. It was this May that Ashwani got in touch with us saying that he wanted to fix up a clock in Kasauli. Photos were shared and we discussed the problems in that clock and ideas on how to fix them. A motivated and resourceful man Ashwani is, he managed to get in touch with the military engineers in Kasauli and brought all his collected knowledge to the men with the skills and tools to do something about it! And our uniformed men have quickly shown us that we have every reason to salute them.

Military Engineers at work on the Kasauli Clock.

Military Engineers at work on the Kasauli Clock.

This is a success story. The tale of one man who saw something that could be done and got down to doing it… our team began in the exact same way. The Kasauli team has crossed milestones to reach where they are. We work on similar goals now, to keep our clocks running on time, challenging the elements that slow or stop it. We share a world of monitoring gears and tweaking pendulums. But in Pilani, our behemoth gives us an additional task of 9 more bells and separate tune machinery to solve… and solve it we will!

For the moment though, lets shower some applause on the men who have fixed a piece of their own little town’s heritage. We’ll be posting a link to their website once it’s up, but until then, more details of their work and the people behind it are on this page.

Welcome.

The most iconic landmark in the quaint, little hamlet that is Pilani, the BITS Clock-tower brings with it more than half-a-century’s worth of history and tales aplenty.  Occupying a central place in BITS folklore, over the years, attempting an ascent of this structure was something of a rite of passage for every BITSian who hopped onto the life-mobile and sauntered off into the sunset.

As clock-towers go, this specimen is about as unique as they come – its array of 10 bells, gives it an unparalleled musical range among its brethren nationally, and it certainly hits rarefied notes on a global scale.  That it has had to suffer in silence for the last 30 years is a deafening tragedy, with reports from its heyday extolling how its chimes could be heard from miles away!

Over the last couple of years, there has been a dedicated student-run initiative to restore this tired behemoth to the pristine glory of its yesteryears.  Mentored by a group of recent alumni, a team of able hands and minds have made great strides in this regard.

Wishing you well, ye old Methuselah. Long may you enthrall generations hence!

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Discussions on how to solve the cable interference

We’ve got some ideas on how to solve the problem of cable fouling. Some of them look like permanent solutions, some are temporary ones that can be used to prevent cable damage until we can assemble a permanent one…

Disclaimer: Dear Engineering Graphics instructors, please do not revoke our good grades. All the drawings below are rough concept sketches that we made during our discussions. 

  1. Rerouting the Clock wire-rope.

The fixed end and the pulley mount of clock driving weight cable can be exchanged to move the clock cable to the left (when viewed from FD2 side). The two points to be exchanged are encircled in the picture below. This will involve a lot of work as the clock will need to stopped and whole driving weight removed.

  Rope discussions-1  


  1. Putting a spreader bar/ separator

A spreader/ separator can be designed to prevent fouling/ rubbing of cables. The bar will have to be designed to accommodate gap variance as they unwind. 


  1. Relocating the carillon Pulley on tank

Relocating the carillon pulley on tank instead of clock cable pulley(on tank) is much easier and can be done without Bheems help. The pulley can be moved sideways such that it is still under the narrow rectangular opening on the clock floor through which the cable passes. As long as it is under the opening it will not rub with the wooden flooring of the clock chamber. A new mount for the pulley  can be fabricated easily by welding a few plates of 6-8 mm steel together, similar to the ones used for making pulley clamps. Refer to the figures below :

Rope discussions-2Rope discussions-3

Yellow line- Clock driving cable

Black line – gong and carillon driving cable

 


  1. (RJV)- An easier way of achieving the same outcome as above would be to fabricate a single additional plate to replace the straight plate of the existing clamp. The new one can be used for an offset of up to 300mm if you want. Note that this arrangement will apply a torque along the axis of the I-beam. (CCW in this image) Check that the mounts holding this beam to the N-S beam below it are secure.

Rope discussions-4



  1. A temporary action can be thought about to pull the pulley away from the clock cable. To add a few more s-hooks/one long U-hook to the Tune-barrel pulley, Shift the mounting location to the East on the I-beam to ensure that the cable does not foul with the wooden slot above, and pull the pulley towards the north with another cable attached to the N-S I-beam. I’ve put in a rough sketch below.

Rope discussions-5

 

Back to the tower after the winter break!

 Aman, Pankaj and Arun went up at 16:00 for about an hour. 

The clock was lagging by 5-10 mins on three faces with each face showing  a different time. The SR (back) face was off by 2 hours. We tried to adjust the time  without removing the bevel assembly but couldn’t as there was a lot of resistance. We will need to come back and correct this.

The following changes were observed:

  • The clock chamber floor has been cleaned.
  • New tube lights and wiring (along with PVC pipes) for the clock faces. A new plug point as well.
  • The lightning conductor window was left open and pigeons have started coming inside the bell chamber.
  • 2 broken window glass panes at the room below the bell chamber.