Now comes the time to find out how much you can remember about the movement before you started!

Segregate the pieces into their various categories. As a general guide, the wheels of the striking train will have pins in appropriate places whilst the going train will be comprised of plain wheels. The actual train sequence can be established by observing the gauge of steel used for the arbors and pivots - the pinions next to the barrel will be the strongest and so on right up to the escape wheel.

If you removed the mainspring from a barrel, it must now be re-fitted. If you do not have access to a mainspring winder, you will need the strong leather gloves you should have used to remove it. Having thoroughly cleaned the spring of old lubricant, wipe the surface with a rag coated in mainspring grease. It is not critical to cover the whole surface, because as the spring winds and releases during use, lubrican will spread naturally.

Insert the outer end of the spring onto the hook inside the barrel. When sure that it has engaged, start to turn the spring into the barrel and after each half turn, rotate it. If, after a turn or two you don't think your wrists are strong enough to finish the job, go back now. Once you are half way, you cannot let go and will need to finish the job somehow. Wind in the spring by hand until the centre coils pop in. Take great care with mainsprings as they contain a lot of energy when coiled.

A large mainspring such as one from a fusee clock needs a mainspring winder. Avoid touching the coils of the spring with the piece you are currently winding in.

If you prefer to use an oil lubricant (and Turret clock oil is a favourite for this), apply two to three drops of oil into the coils before snapping on the barrel covers. 

Fit the barrel covers (remembering any punch marks to line up with the barrel) and fit new lines to fusee clocks using the knot illustrated. The fusees, if fitted, should be assembled and a trace of oil applied to the click spring. Check the ratchet for operation before assembly; chain fusee clocks can have the chain fitted later. Placing the back plate on a polystyrene block covered with a lint free cloth or some other arrangement, place the barrels in position. Build up the train in sequence until all the wheels are in place. Remember that some parts may have been screwed onto the inside of the plates.

Any fusee line passes between the appropriate obstacles. The striking train must be adjusted so that it comes to a halt immediately after the last hammer blow. This will allow a good run up next time. Place the front plate on and locate all the pivots in their holes. Try starting with the barrel end of the plates, and fit a tapered pin or nut in as soon as the plates come together. With everything correctly located, lock the plates together tightly and check the motion of the trains using hand pressure. If all is well, the fusee lines can now be taken up on the barrel (not the fusee itself). Spread the line evenly across the barrel and when hand tight, replace the ratchet wheel and click.

At this stage, replace the hour wheel, bridge and striking mechanism on the front plate. When all is assembled correctly and both trains are not obstructed by over-tight bushes etc., put some power onto the mainsprings. Fusee clocks should be given between 1 1/2 - 2 1/2 turns to the barrel arbor before the clock is wound, depending on the age of the spring. Wind the clock and check that the line is taken up properly by the fusee. Once on, it will look after itself. Check that the stop work (usually an arm attached to the inside of the plate) operates to prevent the clock being overwound. This will obstruct the fusee when the line passes near it.

Repairing Your Own Clocks by Mervyn Passmore