Keep the Atmos clock out of direct sunlight and avoid exposure to excessive hot or cold temperatures. The gold plating and lacquer on the case of the clock is very thin. Never use household cleaners or abrasives of any kind. Clean fingerprints and dust from the case with a very dilute, mild detergent and a soft, non abrasive cloth.

The Atmos clock is very sensitive and can react significantly to very minor adjustments. If the clock is running too fast or too slow, use the adjustment lever on the top of the frame which is just behind the dial at the twelve o clock position. Moving the lever anti clockwise this speeds up the clock and turning the know clock wise slows down the clock.  The lever is marked A for advance (speed up) and R for retard (slow down).  Move the lever half a turn and wait several days or a week for the clock to adjust and if necessary repeat.

Once the Atmos clock has been levelled and the hands set, the locking mechanism can be undone. The pendulum should start to rotate and then keep oscillating backwards and forwards. It is best to set the hands a minute or two in advance before the door is put back in so that the lever can be released at the correct time. If the clock was stopped abruptly or accidentally jarred, do not spin the pendulum round by hand as this can damage the suspension spring and the escapement mechanism. To start the clock again, gently move the pendulum in either direction by about half of a complete rotation (180°) using something like the eraser on the end of a pencil.

Set the clock to the correct time by using the minute hand only. It is best practice to move it in a clockwise direction and only when the pendulum is at, or about to reach, an extreme in its swing, or is locked. Do not touch the hour hand or move the minute hand backwards on an Atmos clock. When the summer comes in the Spring to change the clocks for British Summer Time, just stop the clock with the lever, when the pendulum stops moving, and move the minute hand forward by an hour. In the Autumn it is easiest to just stop the clock and restart it after an hour has passed.

Atmos clocks are designed to work best when placed on a stable, level surface that does not suffer any jarring. Use the spirit level at the front of the base plate to level the Atmos clock.  To level the clock the two feet at the front of the clock are raised up and down by the screws just inside the front case to assist with levelling the clock, adjust these until the bubble is completely central. If the clock will not level within the maximum adjustment of the screws, use a shim or packaging under the appropriate foot.

An Atmos is locked with the lever below the dial, it is locked in right hand rotation so that when the clock is set up and the lever is released by pushing to the left the clock will start on its own.  It should remain locked until you are ready to set the Atmos clock in its permanent place.  Moving the Atmos clock without locking the pendulum can cause serious damage to the movement.The correct time to lock the pendulum is when it reaches an extreme swing, i.e. it stops moving. Do not lock the clock whilst the pendulum is in mid-rotation.  The locking lever is quite stiff so push as gradual as you can whilst holding the clock steady.

Place the winding key into one of the winding holes and wind in a clockwise direction. As you do this it’s advisable to have the trunk door open so you can see the weights as they travel upwards into the case. As you approach the top slow the winding down and you will feel the brass pulley touch the bottom of the seatboard. Do not wind any further!

To do this you adjust the regulation nut which is at the bottom of the pendulum. If you turn the nut to the right you will speed up the clock and if you turn it to the left you will slow down the clock. You should hold the pendulum shaft with one hand with a little downward pressure and adjust the nut with your other hand so you do not unhook the pendulum.

To put the clock to the correct time you should always move the minute hand in a clockwise direction until you reach your current time. You must allow the clock to strike as you come to each hour or striking problems may arise. One of the main rules for antique longcase/grandfather clocks is never to turn the hands backwards. This can result in damaging the movement and it will probably need to be repaired.The date will also need to be adjusted if the clock has one. This can usually be done from the front of the dial by moving the date ring or disc to the correct date. If there is resistance then the date is currently in gear and you will have to take the clock forward in time to ascertain when the date changes. The dates on longcase/grandfather clocks change either every 12 hours (half a day) or they change once every 24 hour s. You can also change the date by moving the hood and locating the disc or ring behind the dial.

Listen to the tick if the tick is uneven then you will need to adjust the crutch to obtain an “In Beat” tick. Holding the pendulum bob in a central position move the bob to the right and then back to the left. If the longest gap is when the bob is swinging to the right then the crutch needs to be bent to the left and if the longest gap is when the bob is swinging to the left then the crutch needs to be bent to the right. With small adjustments on both sides you should obtain an even tick. If the tick is uneven the clock will usually stop. It’s also important to make sure that the suspension block is in a central position within the crutch loop. Bending the crutch either forward or backwards will solve this problem crutch shown below.