This is great information, some of which confirms my doubts. I trust too, that having gone down part of this track before, I haven’t bored the socks off any of you gentlemen.

Put simply, I have of necessity, become a skinflint.

Although there have been a couple of reasons why the main spring needs cleaning, I no longer have the correct means of removing it from the barrel. In fact, I never have.

NB – IT’S TOO DANGEROUS WITHOUT THE RIGHT EQUIPMENT!

It has been suggested elsewhere, that I wouldn’t need to remove the spring from the barrel if I washed it in petrol, and then applied grease. If greasing is the better approach, it should be possible to apply a tiny `drop’ between each layer as I wind it. In view of the above, that will have to wait until after the clock is fully assembled

Gordon, I considered Vaseline, but it melts at about body temperature. Watching the clock dripping stuff could be embarrassing in a Melbourne summer. Then again there wouldn’t be much of it. With my limited knowledge in chemistry, I have to ask – Why should a grease based upon silicone or lithium cause concern?

Thanks for your comments about Vaseline, KWIL. Spraying on a lubricant is not an option for me, having spent time testing and applying shellac lacquer to the brass in the past few weeks. I could of course decant some onto a wooden toothpick, and poke that where needed. (And nowhere else!)

The pivots, pallets, and impulse bits require the absolute minimum of oil but, on this clock at least, they are always accessible. Advice from several quarters has shown me the way to lubricate the clock, and that using a minimal amount of clock oil is very important.

Gentlemen,

Thank you for this renewed interest.

Although it was August last year when I was querying the use of plumber’s grease for my skeleton clock, this is now a good opportunity to make a few additional comments.

In the intervening period, I was fortunate enough to make contact with a group of very professional clockmakers/ repairers here in Melbourne who put me wise to what was need with regards to clock lubrication, even supplying me with a few mls each of three grades of oil. Upon their request, I took my own bottles. The thickest grade (for the main spring), had a smell similar to heavy engine oil, and reminded me of that used in automobile differential gear boxes.

It was emphasised to me that the amount of oil to apply should be minimal, otherwise it would begin to be `pulled’ out of the bearings by a combination of capillary action and gravity. I was somewhat surprised by this until I watched what happened. Sure enough, even though the bearings were slightly recessed, any excess would appear to drag oil out of the bearing and down the sides of the clock plates.

In addition, I became rather concerned about the faint crunch each time I turned the winder key, and it was this sound/feel which caused me to think that the main spring needed lubricant. Then I realised that this problem was due to the fact that I had not managed to get enough oil into the end bearings of the mainspring barrel. Once I did this, most of the `crunch’ disappeared and so did a growing variability in the clock’s time-keeping. It was rather curious to realise that as the main spring ran down, the clock would gain speed. A reexamination of the balance wheel and lever escapement was sufficient to show that under this `run-down’ condition, the balance wheel swings through a smaller arc to produce a quicker beat. One source of this variability comes from the design of the fusee, but that's another story. Meanwhile, my pictures may help those of you wishing to know more.

Melbourne can be a rather dusty place, so the matter of a sealed cabinet had been addressed earlier in the build. My solution was to get the local glazier to make me a plain glass (five piece) cover from 3mm glass, sealed at the corners with silicone. I should point out that access to the clock for winding means that the cover needs to be easily removed. I therefore made the wooden base with a groove to accept the bottom edge of the glass. This groove was carefully lined with a bulky fabric so that while air could leak through this labyrinth (to compensate for the changes in ambient temperature and pressure), dust would be excluded.

Thanks again for your interest.

Regards to all,

Sam