Developer´s Blog
  • I thought I would start the Nonus discussion with a kind of developer´s Blog.
    I wanted to achieve 2 things, firstly have the pendulum impulsed only once in 60 secs, and to have the impulse amount divorced from the drive force of the clock.
    An escapement has the disadvantage of being in constant contact with the pendulum, so at no stage is the pendulum allowed to swing freely, the deadbeat escapement goes a long way to solving this problem, but even when the escapement wheel tooth sits against the “dead” face there is still contact between escapement wheel and anchor.
    Impulsing the pendulum once every 60 secs means the pendulum can free swing between impulses, there is of course amplitude /speed differences between impulses, but the decay remains constant from cycle to cycle.
    Another disadvantage of an escapement is it is always dependent upon a constant drive force, fluctuations do/will have an influence on the period of the pendulum. An excellent solution to this is the use of a remontoire. And the impulse drop weight in the Nonus could be seen as such. Variations in drive force do not affect the impulse, either the drive weight can lift the drop weight or it cannot, simple as that.
  • I have a question concerning the frequency of the pendulum: cause it has no contact with an anchor that "forces" its movement, will the pendulum be more sensible than other pendulum clocks to any alterations to its swing arc path, e.g. air movement. Or at the end of a 24h cycle, every increment or decrement alterations of the pendulum swing time, will have little effect on its accuracy?

    Anyway, my wife loves the Sextus I'm building from your kit, and asks for a new one. Will the Nonus have a kit also? Both of the 4 days and 8 days running time Nonus? Cause I'm sure will be the next one (well, Nonus and/or Septimus, all depends on wife's mood after first one finished ;)

  • I'd also be quite interested in a kit for the Nonus. I'm looking for something to give my son and his wife as a belated wedding gift and a Nonus might just fit the bill. Although I eventually intend to try building a clock from scratch, a kit would be good for a gift as it would be of much higher quality than anything I'll manage - and much more likely to work!
  • The most accurate pendulum is a free swinging pendulum, but obviously totally useless for clocks as it will eventually stop swinging without an occasional push, the next best thing is a pendulum that does as little as possible.

    That is the case with the Nonus, the decay between impulses is so little as to be negligible.

    The Nonus Pendulum is affected by air pressure change and air movement as much/little as an escapement driven pendulum, so no difference there.

    The Nonus is my most accurate clock to date, and in some ways the simplest, as it is very much split into 2 sections, the one being the drive force that lifts the drop weight and turns the hands the other is the pendulum and counting wheel/ triggering mechanism. Which makes troubleshooting easier.

    I will be offering the Nonus as DXF plans as well as a complete kit.

    I hope that answers your questions.

  • How will the 8-day be different to the 2-day version? I'm assuming you'll need more gearing and, consequently, a heavier weight to drive it? It struck me that with the clock I built, especially, when, say, trying to adjust the time via the hour hand - is that the extra gearing leads to pretty bad jamming of the gears.
  • Well actually not much difference between the two, on the 8-day the drive weight will have a pulley effectively increasing its drop length by 2, which of course also means the weight will also increase from 2 kg to 4 kg.

    The biggest difference will be the winding, both are string pull wound, as with the Septimus, but the 8-day will have a separate winding barrel just to the side of the drive arbor, connected by gears to give the winding barrel a 1 to 2 ratio, which means the pull string moves the same distance as 4-day but winds twice the amount. Plus the arbor from the separate winding barrel, provides a hanging point for the other end of the drive weight string, so 2 birds with one stone.

    By the way I would be wary of adjusting the time by using the hour hand, as its 1 to 12 ratio also increases the clutch holding strength by 12, which puts quite a lot of strain on the hour hand fixture, not with all clocks but with most.
  • Ahh, very interesting - firstly, re the hour hands - mine is impossible to adjust that way - the intermediate gears between the twos visibly move on their arbour and jam. The clock works perfectly well otherwise - as you said elsewhere, there's very little power or accuracy needed on those gears.

    The Nonus design sounds fantastic. I think if I had the tools and experience, the one change I might want to make with the basic design of the clock like the sextus whould be to fix a handle to the barrel arbour to allow it to be rewound by turning the handle, rather than a draw string to rotate it. Not that there's anyting wrong with the drawstring, but it just appeals slightly to my tastes.

    The Nonus design definitely sounds like a major step up in terms of complexity - not a clock for a beginner?
  • Actually the Nonus´s bite is not half as bad as its bark, it may look like a complicated clock, but the major hurdle is actually understanding what it it does, once you have (and believe me it ain't no rocket science) the rest is easy.

    It comprises of 2 very separate parts, the one is the pendulum and count wheel, which is very easy to get running, and the second is the drop weight, either the drive weight is able to lift or it is not. None of the ambiguity of too little/much drive force as with a grasshopper.

    The difficulty was arriving at the final design, the setting up was a doddle.

    The reason I went for string wound is that the arbors are static so the cogs turn on the arbors, so it is not just a case of adding a key to the drive arbor and winding. It would have been possible to add a key winder, but I would have had to do some major redesigning which would have ruined the simplicity of the whole.

  • Hi Dave,
    I was looking every day to buy the plans for Nonus. Can you kindly advise when do you think they will be available for sale? I am dying to start working on this clock.
  • @Mihai

    Making and designing a clock actually takes a lot less time than getting it ready for publication, the instructions take the longest, but there are also materials to be sourced, DXF data to be produced, tutorial video to be made and constant checking and rechecking to ensure there are no mistakes. All this on top of my normal workload. I am not after the sympathy vote with this, but just want to explain why there is so much time between the first "viewing" of a clock and its publication.

    I still need a couple of weeks until I am satisfied enough to offer the Nonus, but I will be sending a mail to all Woodentimers when plans/kit are available.

  • Hi Dave,
    Thank you for your explanations, even though I knew is a long and intricate process to make such a piece of art ready for sale.
    I don't want to push you in any way, but I want to ask you some info regarding this particular clock:
    I am going to order some brass rods and tubes from Austria (the website you recommended) and I want to make sure I will order all necessary dimensions. Therefore, I want to ask you for a brief description of brass rods and tubes used for Nonus. I want to include all rods and tubes into one single order to avoid double shipment charges.
    Thank you very much for your support!
    Mihai :)
  • @Mihai

    The materials list is the last thing I do when writing the instructions, but here is a rough list.

    Brass rod= 3,4,6 mm
    Brass tube= OD 6/ID 4 and OD 8/ID 4
    Threaded rod = M4 brass and M3 steel
    Carbon tube = OD 6/ID 4

    Carbon tube should be 100 cm long everything else 50cm.

  • Thank you Dave!
    I already submit my order. Please can you mention the vendor from where are you buying Carbon tube?
    Mihai :)
  • @Mihai

    The carbon tube is OD 6mm ID 4mm, my supplier only delivers to the EU, but just google for carbon tube and you will get lots of results.

  • Having just managed to log onto the forum, I am impressed by the comments about drill machines and builders who have been cabinet makers - I am trying to build the Nonus kit using a 'workamate' folding bench and an electric hand drill - time will tell if I am to be successful, in the meantime it's great fun.
  • Alan, what a great idea for a discussion thread.
    "Minimum tools to build a Woodentimes kit"
    Do keep a diary of your progress, and post regularly on here.
    There is a photo diary here
    by someone who built a working Sextus on his living room floor.

    Best wishes
  • Hello there... Still waiting for my nonus 8 to arrive to italy and already I have doubts... Will I be able to build it? I watched all the videos and dreamt on it so many times I do know every millimeter of that clock... Thence my first question: when on the instructions it is written "glue" but not specified (epoxy reain), does it mean that I should use vinylic glue? Thanx! Wish me luck!
  • I would recommend Regular LePage wood carpenter yellow glue
    Don't take Express version though. It's hard to adjust parts when it dries in seconds. Get regular one.

    Do not take Gorilla. It's heavily advertized but very bad. It blocks the exit and gets dense fast, so you will throw it out soon.
  • My clock has been running smoothly for at least a month. Now it will not run more than a minute without stopping. Any suggestions?
  • With regards to wood glue, I've had great success with titebond 2 brand. Decent open working time with a quick set