Technical Library

KEYBOARDS IV: Keyboard problems

K E Y B O A R D P R O B L E M S	OBSERVATION	CAUSE	CORRECTIVE ACTION
	Key sluggish in return.	Balance mortise swollen with humidity.	Ease balance mortise, preserving round hole at bottom of key, and parallel sides of mortise at top.
		Balance pin dirty or corroded.	Clean or replace balance pin.
		Balance pin bent.	Straighten balance pin.
		Key loose front to back on balance pin.	Restore bottom of balance mortise.
		Key wobbles sideways on balance pin.	Restore top of balance mortise.
		Key lead has corroded.	Remove key lead corrosion.
		Odd key is head heavy, or there is insufficient weight in the tail to overcome friction.	Rectify incorrect key balance by carving or using a weight to match surrounding keys.
		Keylevers left rough from being sawn apart.	Plane sides of offending keylevers smooth.
		Key end cloth is catching on the touchrail or adjoining key’s cloth.	Trim offending keyend cloth.
		Poorly located cloth nail has penetrated key side.	Relocate offending cloth nail.
	Key loose front to back.	The hole at the balance point on the bottom of the key is damaged or worn.	Restore bottom of balance hole to circular shape.
	Key wobbles sideways.	The balance mortise is damaged or worn at top.	Restore parallel sides at top of balance mortise.
	Excessive side to side motion of key.	The thumbnail at the rear of the key is too thin.	Replace thumbnail.
		The lower manual guidepin has been filed too thin.	Rotate or replace the guidepin.
		The slot in the rack has been worn or damaged.	Restore the slot in the rack to original dimensions.
	Key flops side to side unhindered at all times.	The guidepin is missing, or too short to reach the rack.	Replace guidepin.
		The thumbnail is missing or broken.	Replace thumbnail.
		The plastic key insert is dislodged.	Reseat plastic key insert.
		The plastic key insert is missing.	Replace missing plastic key insert.
	Key flops side to side unhindered when depressed.	The guidepin or thumbnail is too short and is leaving the rack.	Replace guidepin or thumbnail of sufficient length.
	Keyhead displaced sideways.	Keylever has warped because of climate change.	Bend or relocate guidepin, or in serious cases, wedge the key lever.
	Scratchy noise when key is depressed or released.	Guidepin is rough and rubbing on the rack.	Smooth guidepin and lubricate rack slot if necessary.
	Key squeaks when played.	The rack slot requires lubrication.	Lubricate rack slot with soft lead pencil.
	Clacking sound when key is depressed.	Accidental key is hitting natural keycover.	Realign accidental key.
		Underside of accidental keylever is hitting balance rail.	Check that keydip is not excessive before adjusting key to allow for clearance.
		Underside of natural keylever is hitting frontrail, casefront moulding, or coupler rail.	Check that keydip is not excessive before adjusting clearance.
		Keyend cloth is worn.	Replace keyend cloth.
		Keyend cloth is not correctly located on key.	Correct keyend cloth location to provide sufficient padding for jack bottom.
		Bottom of jack is hitting on a nail used for fastening the keyend cloth.	Ensure nail is fully inserted, or relocate nail.
		Top of jack is hitting on a nail used for fastening the jackrail cloth.	Ensure nail is fully inserted, or relocate nail.
		Insufficient jackrail padding.	Replace jackrail cloth.
		Guide pin or thumbnail is hitting touchrail.	Relocate guide pin or thumbnail lower in key tail.
		Tongue axle pin has worked loose and is projecting from side of jack.	Reseat tongue axle pin flush to side of jack.
	Clacking sound when coupled lower manual key is depressed, particularly in midrange.	Underside of upper keyend cloth is worn.	Replace upper keyend cloth.
	Clacking sound when key is released (especially accidentals.)	Italian nameboard has warped forward.	Investigate an unobtrusive method to keep nameboard flush against wrestplank.
		Coupler rail has bowed downwards.	Pack coupler rail higher to avoid bowed effect, and pad underside if necessary.
		Rear of accidental key is hitting the nameboard batten.	Check and secure keyframe position.
			Check & adjust coupled position of upper keyboard.
			Ensure nameboard batten is screwed to nameboard.
			Restore clearance between rear of accidental key and nameboard batten.
	Key is not level with its neighbours when at rest.	Key is not fully returning.	Diagnoze and fix.
	Key is not level with its neighbours when at rest.	Keyboard requires leveling.	Level keyboard.
	Key is above the level of its neighbors when at rest.	There is foreign matter under the key at the balance point.	Lift key and remove foreign matter.
	Key is below the level of its neighbors when at rest.	There is foreign matter under the key at the backrail.	Lift key and remove foreign matter.
	Keyhead is tilted so playing surface is not level.	Balance pin is not vertical.	Realign balance pin.
		Key coverplate has warped.	Reglue coverplate to keylever.
		Key has twisted.	Realign balance pin to suit, then adjust level to surrounding keys and spacing.
	Uneven keydip from key to key.	The instrument has never been regulated, and the cut jack tops are uneven.	Regulate instrument and trim jack tops to consistent height.
	Uneven keydip from key to key.	Jack bottom screw has pushed into its hole.	Restore hole for jack bottom screw and reinsert.
	Excessive keydip at either extremity of compass.	The jackrail cloth is too short.	Ensure jackrail cloth is sufficient length for entire compass of instrument.
	Insufficient keydip: The instrument cannot be played.	Jackrail has been put on backwards.	Install jackrail correctly, observing any markings on underside.
	Accidental keys bottom out below level of natural keycovers.	Keydip is excessive.	Reduce keydip.
		Accidentals are too short for keyboard geometry or regulation.	Raise accidentals with punchings at balance rail.
	Lower manual key sticks at limit of keydip.	Insufficient clearance between keytail and rack.	Trim keytail to provide clearance at limit of keydip.
	Upper manual key sticks at limit of keydip.	Key is not tracking vertically.	Realign guide pin.
		Guide pin has been knocked out of position when keyboard returned to instrument.	Realign guide pin.
		Guide pin mortise does not have parallel sides at top.	Restore parallel sides of guidepin mortise.
		Upper keytail is rubbing against 4⁠´ jack.	Reduce ON position of coupler.
	Upper manual keys move slightly when keyboards are being coupled.	The coupler dogs are too long.	Regulate height of coupler dogs.
		The cloth tabs supporting the upper keyboard have worn.	Inspect and replace cloth tabs.
	Upper manual keys move slightly when lower keyboard is played, even though keyboards are uncoupled.	The coupler dogs are interfering with the keys.	Increase OFF position of coupler.
	Upper keyboard can skew sideways when coupled or uncoupled.	The upper keyframe is not confined to the coupler tracks.	Modify coupler tracks to confine upper keyframe.
	Depressing a lower manual key plays two adjoining upper manual keys.	Coupler dog is interfering with adjacent key.	Shape coupler dog to remove interference.
There is too much side motion in upper keyboard tracking.		Reduce upper keyboard side tracking.
Delay before upper manual keys move when coupled.	Excessive lost motion in coupler.	Reduce lost motion in coupler.
Lower manual key clacks when played in coupled position, but not uncoupled.	Coupler dog is hitting a cloth nail on the upper key.	Reposition cloth nail.
	The underside of the upper manual keyend cloth is worn from the coupler dogs.	Replace upper manual keyend cloth.
Lower manual key clacks on release.	Keycover is hitting coupler rail.	Raise coupler rail.
Upper keyboard clunks during coupling or uncoupling.	Insufficient or worn padding on coupler stop blocks.	Inspect and replace padding.
Upper keyboard clunks during coupling or uncoupling.	Boisterous performer.	Encourage a more gentle approach to the instrument.
One key jams down by itself.	Slot in rack is too tight at top.	Ease guidepin or thumbnail.
One key jams down by itself.	The thumbnail has dislodged from the key and is stuck in the rack.	Reglue thumbnail in key and check for correct operation.
Two adjoining keys stick.	There is a foreign object stuck between the keys.	Remove the foreign object.
Several keys play together and jam in down position.	Corroded key leads have expanded to interfere with adjoining keys.	Remove key lead corrosion.
Several keys play together and jam in down position.	The keyboards have not been correctly transposed.	Raise the offending jacks and let them return by gravity to their correct key tails.
Top key flops down without playing.	The keyboards have been transposed up, but this instrument has no action for the top note in the transposed position.	Normal operation.
Lower keyboard keyframe position indeterminate.	The instrument relies on keyboard holddown screws, and these have been removed.	Replace keyboard holddown screws.
Lower keyboard keyframe position indeterminate.	There is slop in the keyframe position because of climatic change.	Determine correct keyframe position and reduce lost motion.
Impossible to remove transposing block.	The block is screwed to the keyframe.	Remove action to access keyframe and remove transposing block screws.
Impossible to remove transposing block.	The space for the block has been squeezed because of climatic change.	Use an appropriate amount of force to dislodge block, and lubricate or adjust before returning.
Keyboard won’t slide sideways to transpose.	The instrument relies on keyboard holddown screws.	Find and remove keyboard holddown screws, replacing after transposition.

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