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Longcase/Grandfather Clock Setting Up Guide

Start by placing the clock case in the position required. It's a good idea to have a helper during the setting up to process to prevent damage. With 8 day clocks the movement is usually attached to a seat board, place the movement board on top of the case trunk and get your helper to hold it in place. 30 hour clocks seat boards are often separate and so the rope or chain and pulley will have to be passed through the centre slot and then put up onto the trunk.


A: Crutch Arm, B: Crutch Fork, C: Top Suspension Block, D: Suspension feather, E: Lower Suspension Block, F: Pendulum

Now with the movement still being supported by your helper, hang the pendulum as shown in the sketch above by putting the pendulum up through the trunk door, up through the seat board and through the crutch slot, place the suspension feather into the slot of the back cock and seat the top block down into the notch. Now the pendulum is on, there is less likelihood of the movement falling forward however it's still possible to fall forwards.

Ensure the case is now level and standing firm, this is very, very important. If there is a deep skirting board you may need to position a piece of similar size wood across the back of the case to allow the case to stand level once this has been achieved and the pendulum swings freely it is recommended that the case is fixed to the wall using a existing hole through the back of the case.

The next stage is to slide on the hood. Adjust the seat board from underneath until the dial lines up perfectly in the hood frame. Remove the hood again. If an 8 day clock the lines should  untangled and ensure that the lines are sitting correctly on the wheels. Hold the line about one foot down from the board and pull it tight. Place the winding key on the square and wind very slowly, whilst keeping the line tight and watching it feed onto the barrel grooves. Without releasing the tension on the line to ensure there are no loops or kinks, turn over the pulley and place the line in the groove. Then hang on the weight making sure to keep the line tight until the weight is in place. Repeat the same procedure with the other weight. For 30 hour clocks check that the rope or chain is correctly seated on the sprocket within the movement turn the pulley up the correct way and hang on the weight.

Hand Setting

For most longcase clocks where only the hour is struck, move the minute hand ONLY in a forwards direction pausing at each hour to allow the clock to complete its strike stopping when the required time is reached.

Strike Setting

Most 8 day clocks are rack striking and so the sequence should not differ from the time. However in early clocks of 8 day or month duration the locking plate system was sometimes used which may become out of sequence at some point. To correct these, first remove the hood and look at the left hand side of the movement. On the very back plate or in front or behind the largest wheel, attached to the barrel, there will be a wheel without teeth but with notches cut into its circumference at uneven intervals. Resting on this locking plate circumference will be a lever, which must be raised and released to activate the strike. Continue to release the strike until the number struck coincides with the time. For 30 hour clocks most are locking plate striking and will probably need correcting fairly frequently if allowed to run down. The locking plate should be easily found. Use the same method of correction as described above with 8 day clocks.

Date Setting

Three types of date are in common use. The centre date hand, the hand on a subsidiary dial or the date showing through an aperture. Centre date hands can be moved backwards or forwards manually, except when the clock itself is trying to turn the date over a period of a few hours at night, if the clock is set in the correct 12 hour sequence. Hands on subsidiary dials sometimes change every 24 hours or quite often every 12 hours of half a division. The hand can be moved manually but if any resistance is felt at all it should be left to another time as the clock may be trying to turn itself. Two types of aperture dates are used. For those showing in a segmental aperture, the wheel usually turns through half a division every 12 hours and so at certain times it may not be moveable. The easiest way is to gently push round the dial through the aperture in the direction of the figures, counting up until the correct date is reached. Those dates showing a single figure in a square aperture are turned by revolving the date ring from the back of the dial after removing the hood. They can be moved backwards or forwards except when clock is driving the date itself.



The only way of regulating for most longcase clocks is by the pendulum itself. The nut at the bottom of the bob is screwed up to the right (clockwise) to make it go fast and left (anti clockwise) to go slow. It is advisable to hold the bob whilst doing this to prevent the rod being twisted and damaging the suspension feather.