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mbhorology

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  1. Currently working on a carriage clock which amongst other things has needed a replacement balance jewel. I'm beginning to reassemble, but the dial has a big issue in that it has lost 3 of its feet! There is only one foot remaining and even that is looking like it might not stand up to too much. What would be an acceptable repair here. Dial spots are an option, but I'd to consider nicer alternatives.
  2. Thanks for the further replies. Just as an experiment I made a new eye on the mainspring which came out of the clock. It is 0.28mm thick and the clock is now running at a fair amplitude. This spring is however far too short (it measures about 600mm when it needs to be about 1000mm). I also fear it breaking again and causing damage. It is also set, when removed from the barrel, it doesn't open up much like you'd expect a new spring to be. I think I'll give up on the idea of hardening and tempering the annealed material I got from M&P. Does anyone know of a supplier where I might get hold of spring material of this size? I've tried my usual sources of M&P, Walsh and Cousins. 2.4mm is in there now, I might get away with 2.5mm. From calculations above and my own experiments needs to be 0.27 to 0.3mm and around 1000mm long.
  3. Regarding the question about the car it came from, I'm trying to find out. Currently the clock is mounted in a wooden mounting to hasn't been in the car it came from for many years. Thanks also for the spring calculations above. I've been backing this up by reading the section in George Daniels Watchmaking book. So I'm now in a position to know what I need, but where can I get 2.4mm height x 0.26 spring material from? M&P sell it annealed and I can't see anything from HS Walsh or Cousins. The closest I can get is my pocket watch mainspring which I got from Cousins... it is however far too short and not thick enough. It runs for a few cycles at very low amplitude. I feel if I had the correct spring as calculated above it would work...
  4. I'd totally missed the 4 day duration staring me in the face of the clock! So yes I agree the calculations can be revised: - 4 days + 1 = centre rotates 120 times - Barrel rotates 11.5 times <update from earlier comment> I need to understand how that calculator works...
  5. Thanks for the replies. I've already estimated the spring dimensions so I should have included my calculations and train information. These are my calculations, but I'm happy to be corrected. - Centre pinion = 10 leaves - Barrel = 104 teeth The centre is driven directly from the barrel so essentially its a big watch! So thinking about the turns of the spring for different running periods, I started with 30 hours. - the centre would turn 30 times, so the barrel would be 30 *(10/104) = 2.3 turns - unlikely as the resulting thickness of spring would be very powerful So considering again, would it run for 8 days? - the centre would turn 192 times, so the barrel would be 192 * (10/104) = 18.4 turns - which feels like lot! The proportions of the barrel are quite large so going with this the barrel dimensions are: - Barrel diameter = 30.3mm - Winding arbor diameter = 9.2mm So based on 1/3 arbor, 1/3 spring, 1/3 space the spring would occupy very roughly 5mm So if I turned a spring 18 times around the arbor the resulting thickness of spring would be 5/18 = 0.27mm That feels about right given that I've got it running with a very low balance amplitude on a 0.2mm spring. So taking it a bit further and using the M&P spring calculator it confirms that my spring would be between 970 and 1200mm The spring is 2.4mm high... The closest I've been able to get is the M&P 2.4 x 0.3 x 1000mm annealed! I didn't realise it was annealed until after I purchased it and I don't fancy risking my own heat treatment and a spring breaking. My difficulty is finding a supplier for this spring material. I need something close to 2.4 x 0.27 x 1200mm. As well as M&P I've checked all the springs from Cousins and no luck! Any suggestions on a supplier?
  6. I'm in the process of working on a set of repairs for an old car clock. It's actually for by final year Record of Repairs for by BHI course. It has requested some significant work to the lever escapement including correcting horn and guard pin shake and the pallet stones needed adjusting for correct drop etc. All very fiddly stuff but it works lots better than before under manual power. So moving to the mainspring, I thought some might find this interesting. Never seen anything like this before, but its not right! For obvious reasons the resilient hooking didn't work very well and slipped after a couple of windings. I ended up breaking the mainspring when I removed it with a spring winder so it needs replacing. It gave way near the inner hooking. Unfortunately the spring is something between a large pocket watch spring and a very small clock spring. It measures 2.4mm high, 0.3mm thick and I've calculated it should be about 1m long from measuring things up. As an experiment I fitted a pocket watch spring of 0.2mm thick and not surprisingly the clock runs but the balance is running at a hopelessly low amplitude. It needs more power! Spring material this size isn't easy to find. I've purchased something from Meadows and Passmore which I thought was ideal (Eureka spring material), the size is spot on, but the material is supplied fully annealed! Perfect for forming the inner and outer hookings, but in this state totally useless as a spring! So to my question. The material needs hardening and tempering; an operation I'm very familiar with for making items like screws. But for a 1m long coiled mainspring that's something to be considered carefully. For the spring to be reliable I'm going to need an even heat treatment especially the temper. So has anyone done this before? I was thinking that I could put the hardened spring on a brass plate and heat it from underneath until it hits the blue colour? Is this madness or should I look harder for the correct spring material?
  7. Edward Powell of Bristol listed as free from apprenticeship and active between 1809 -25. Need photographs of movement to see if it is original to the rest of the clock.
  8. Thanks for the replies. Looks like I'll be going down the route of reducing the thickness some spring sheet sheet to get the right size. I already have some 0.15mm so its not going to take much effort to bring that down to 0.08 as needed. Yes you are correct it is a deadbeat escapement. Specifically it is a Brocot deadbeat escapement which I've not seen on an English made clock before. They must have stolen the idea from a French clock! https://drive.google.com/file/d/1jy65s5Km7TtQ-z60-p4-C5lrXYJhdredXw/view?usp=sharing
  9. The movement is from a Gledhill Brooke time recorder. It is a very heavy duty fusee movement with maintaining work. I have started to remove the rivets from the suspension spring in preparation for a new spring steel: https://drive.google.com/file/d/1PxWHamrbkNqVzRzn3jGQUvOKT8ERgPr2Xg/view?usp=sharing This is a picture of the movement out of interest, but the suspension spring is attached to the back of the case and not the movement. Note the back cock. https://drive.google.com/file/d/1-nVR7AElMVF6sKuqTx4sEJs-p2-zCssVRg/view?usp=sharing
  10. I've got a broken suspension spring which is 0.08mm thick x 10mm wide. Problem is that I can't find a supplier for this thickness of suspension spring steel. 0.15mm x 6mm easy to get, but what about other sizes? Any thoughts on where I can get some from before I consider butchering some cheap feeler gauges.
  11. Finally tried out the operation this afternoon. First photograph shows the dial with brass showing through the silvered section. It was rubbed back with 1200 on a flat block to brass. The numerals didn't need any extra work to refill so it was just a case of silvering the cleaned brass. Using a damp cloth (wearing gloves as I've no idea what the chemicals are) I rubbed in small amounts of Horosilv. It takes a while and initially you think nothing is happening, but gradually it turns silver and you need to work it all over to get a consistent finish. You then wash it in clean water. Next you repeat the operation with Horofinish again applying small quantities and rubbing it even into the dial. Again you clean in clean water before drying and applying the lacquer which smells pretty bad! I'm very pleased with the end result so thanks again for the guidance on this. Out of interest does anyone know what the white powders are? I'd be interested to understand the chemical reaction and what I've been working with other than Horosilv and Horofinish magic white powders.
  12. Thanks for replies. I'll certainly post pictures before, after and during the process which may help others in the future.
  13. Yes it would be for a longcase clock dial. This is the tick in the box I'm hoping to achieve at least for by BHI work. As a sideline I'd also like to experiment with etching my own dials and silvering them too. Maybe starting with a large calibre watch (6497).
  14. For my BHI Record of Repairs one of the operations I need to carry out is re-silvering a dial. I've seen this kit from cousins and wondered if this contains everything I need to try this process out? https://www.cousinsuk.com/product/dial-silvering-kit?code=S1526 I understand that I'll need very fine abrasives to remove the old silvering back to the original brass, then use the items in this kit. Thanks
  15. Thanks - I've found you can get an assortment of sizes from Cousins so I'll reply to confirm. Useful if someone searches for this in the future.
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