Jump to content

Recommended Posts

On 9/17/2021 at 6:45 PM, jkjoller said:

I'm new to watch repair so thought I could get some advice here. I have a Benrus DTU-2A/P MIL that I wanted to practice on. Where would I look for a new crystal and crown?

Thanks.

IMG_3146.jpg.041010f829aa2fa0d8b49041fe9aaea7.jpg

I wouldn't risk it with such a nice watch. I don't know about others, but my first attempts ended with parts lost and parts damaged. I had too few and the wrong tools and too little experience, which must be acquired. I recommend you begin tinkering with Vostok movements (cal, 2409 and 2414). They have Swiss heritage, can be found in the thousands on eBay and cost next to nothing depending on condition.

Good luck! 👍

Link to comment
Share on other sites

I ruined (made irreversible damage) to around half of them at the beginning, but if you decide to go ahead anyway probably you could start with the movement first and if you successfully manage to service it you could go out looking  for a stem?, crown and crystal. For practicing purposes you might want to try to polish your acrylic. (videos are available on youtube). If you want a new crystal and you are in the UK I can send you one or two for free, just give me your address. You would also need a crystal lifter tool, i got a cheap one from eBay and it is surprisingly good. Watch Mark's video as how to replace an acrylic.

Edited by luiazazrambo
Link to comment
Share on other sites

  • Mark unpinned this topic
  • Mark pinned this topic

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.




  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • Yes. I understand (now). I regret to say that I am servicing watches without fulling understanding the cannon pinion function in relation with setting the time  (and many other theory aspects of the orology!!!). If is too tight the hands won't move and on the contrary. If the pallet fork is not installed the train of wheels will spin freely and if the remontoir is on the setting position the motion wheels will also move. I will use HP 1300 for the cannon pinion setting. I am happy and grateful and of course I will report back as soon as I can. Thanks   
    • Hi Fernando, read carefully what @eccentric59 wrote, it is the key to You problem. Lubricate the cannon pinion. Take care to understand what is it's function. When You set time, the train doesn't move, but only the cannon pinion moves. Put hte lever back in it's place, it has nothing to do with time setting
    • Hi fernando. Let us know how you get on.
    • OK, in You case You will assemble the movement with the line attached to the barrel and fusee and will  wind the line  entirely on the barrel after that. It is important when replacing the line to know the correct lenght of the line. The rule is that when line wound on the fudsee entirely, about 1/4 turn still to remain on the barrel. Yes, no tension. The ratchet is not placed yet, the spring in the barrel is complitelly unwound. At the end of the step the fusee is empty and the line is attached to it and strained perpendiculary to it, not on tangent. The escape wheel. Use whatever that will not damage anything. Yes, this is typing mistake, sorry. The word 'pendulum' here is not correct, You should use 'anchor' and yes, it is removed from the movement at this point, according my instruction 1 (Ihave used the word 'lever' there):   Ok, let sey the barrel arbour makes 6 full turns when winding the spring in the barrel from unwound to fully wound state of the spring. Let sey that the barrel makes 4.5 full turns when winding the clock from fully unwound (the line is on the barrel) to fully wound (the line is on the fusee) state. This means that You should not wind the spring in the barlel when adjusting the initial tension to more than 1.5 turns of the arbour of the barrel.  If You make 2 full turns, then when winding the clock, the barrel will be able to turn to only 4 turns, so the limiting device will not limit the rotation of the fusee arbour and You will be able to force the line much more than when the limiting device acts, also the power reserve will be less. Hope this is clear now... Yes, but again - not the pendulum, but the anchour.   About the loosing time... In this kind of escapement, the frequency pritty much depends on the torque. The higher torque - the highrer frequency. This is because this escapement forces the pendulum to oscillate significantly faster than it's own resonant fequency. The frequency depends on the 'depth' of the escapement too - the deeper escapement is, the lower the frequency, and the higher amplitude of pendulum oscillations. The heavier the pendulum is, the harder to the movement (the escapement torque) to force the pendulum to oscillate faster than it's own frequency. And in the end, the own pendulum frequency depends only on the pendulum lenght and a little on the suspension spring 'strenght' This are all the relations between all the factors. You can try to use the old spring (if it is not broken) and see if the clock will work faster with it. Yes, the old springs of fusee clocks sometimes give bigger torque than modern ones, no matter if they seem to be 'set' You can shorten the pendulum to achieve correct frequency. If the torque is reduced, but enough for the movement to work reliably,  then reduced torque will only lead to lessen the wear. The torque in fusee movements is more or less constant all the time, this is the function of the fusee. You can use the Clock Tuner  free app for android to adjust faster the clock rate. You will need to know the BPH of the movement, so count the teeth of the wheels and pinions and calculate the BPH
    • Hi! My bad. I meant to say that when the pallet fork is installed I cant move the wheels "using the crown in the setting position" Really in truly my number 3 was redundant and badly written (trying to explain myself went all wrong). I dismantling partially the watch (calendar, remontoir, Balance and Pallet fork). I think I would need to go that way...  Thanks for your comments...    
×
×
  • Create New...