Kuzma XL AIR KIT User manual

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INSTRUCTION MANUAL
KUZMA XL AIR KIT for STABI XL DC Turntable
S/N:…….......
A r pressure:..............
2019-06

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CONTENTS: Page:
1.0. General 2
2.0. Description 3-4
3.0. Turntable modification 5- 6
4.0. Air supply set up -11
5.0. Platters 12-15
6.0. Maintenance 16
.0. Troubleshooting 1
8.0. Transport 18
1.0.0.0. GENERAL:
1.1.0.0. PRODUCT REGISTRATION AND WARRANTY:
Kuzma products have a non transferable 2 year limited warranty on parts and labour.
1.2.0.0. TECHNICAL DATA:
Mass (total w/o PS and compressor) : 120 kg
Bronze platter- lower 22 kg
Air pressure 4 bars
Dimension-compressor: 180x410x430 mm
Compressor mass: 20 kg
Mains: 110V or 240 V, 50/60Hz (factory set)
1.3.0.0. SAFTEY PRECAUTIONS:
Electrical connection to the compressor from the mains comes via supplied cable. Please keep
compressor away from moisture and be careful not to damage the mains cable. Keep it dry in a ventilated
place above freezing temperatures. See page 6.
1.4.0.0. PACKING:
Be aware that the box is very heavy and that the centre of gravity might not be in the middle of the box.
Inside are cutouts in the packaging blocks of firm foam for various parts of the kit. Some parts are very
heavy, so handle with care while lifting from the boxes and placing them on the assembly surface.
BOX :
2 pcs internal boxes A+B
1 set Double PVC bottles
1 set Silver filters with stands
Box A:
Bronze platter, base with air bearing, brass tonearm tower plate, Allen key 6 mm, 2 sets of 4 mm black
tubes (21+ 4 m), 1 pvc bottle of isopropyl alcohol.
Box B:
Compressor, oil, air intake filter, compressor manual

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Fig. 1. XL AIR kit parts without compressor and silver filters
2.0.0.0. DESCRIPTION:
The XL Air turntable uses an air bearing instead of a coventional bearing which allows improvement of
two important parameters in turntable design. Air bearings have almost zero friction and thus no vibration
in the bearing itself, so no noise reaches the cartridge. The second advantage of a properly designed air
bearing (not simply floating on an air cushion) is a higher load. Adding an additional 22 kg bronze platter
increases the rotational mass of both platters to 44 kg, making it more immune to cartridge drag which
slows down any platter regardless of mass and drive.
Conversion into an XL AIR version is simple but requires some technical skill. Using a high pressure air
supply ( 4 bars) requires you to follow the instruction manual until you become familiar with what is
required.
The air bearing actually consists of two bearing surfaces. The top surface carries the vertical load while
the cylindrical hole carries the horiontal load. The air bearing surfaces are made from porous carbon which
has milions of small holes to let air pressure out. This creates more uniform pressure inside the bearing's
gap thus making the air bearing stiffer with zero movements.
2.1.0.0. MODIFICATION:
This can only be done on an XL DC turntable. If you have XL, XL2 or XL4 version you would need first
to covert your turntable into XL DC version( AC motors in older versions will just not be able to rotate
such a heavy mass turntable).
The upper part of the base is replaced with a new upper base which holds the air bearing. The new
subplatter with the air bearing shaft will support both platters.
The bronze platter (22 kg) fits on the new subplatter and supports the existing platter. The mat height is
now 40 mm above the supporting shelf. For this reason the tonearm tower also needs to be raised with an
additional tower support brass plate. Fig.1.
An air compressor supplies air pressure flow to the air bearing base.

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2.2.0.0. AIR PRESSURE SUPPLY:
This consists of the compressor, silver filters and tubes.
2.2.1.0. A r pressure l ne
NOTE: The air supply line is under high pressure 4-8 bar so do not disassemble any parts under
pressure. Turn off the compressor and release pressure from the air supply line.
Pressurised air flow comes from the compressor via the black PVC tube to the silver filters. From the
silver filters the air flow goes via a black PVC tube to the base with the air bearing (turntable). The air
bearing requires clean air to function properly. Air contains dust particles, water and oil moisture and
these are removed using filters along the air supply line.
2.2.2.0. Compressor
This creates pressurised air flow ( up to 8 bars). Position the compressor in a suitable place with its own
mains outlet. It generates heat and requires natural ventilation to cool down.
The compressor has 3 filters built in. The first filter is an air inlet to filter dust, the second filter is below
the pressure regulator and the third filter collects condensation from the compressor’s reservoir. The
compressor’s automatic system removes all this debris via three tubes into double PVC bottles. Fig. .
2.2.3.0. S lver f lters
These filters remove the final fine dust and moisture from the air flow just prior to the air
bearing.Fig.6&11..

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3.0.0.0. STABI XL DC MODIFICATION:
3.1.0.0. AIR BEARING BASE FITTING:
NOTE: Some parts are very heavy, so be careful when handling!
NOTE: Choose a suitable supporting table which can hold over 120 kg kg without warping. If you
are using more than one tonearm tower be sure that the support can handle the extra mass.
NOTE: While the parts are packed in plastic bags for protection, these are not intended to be
strong enough to lift or carry the contents.
3.1.1.0. Remov ng parts:
Remove tonearm tower and protect your cartridge. Remove platter, belt, subplatter and motor tower.
Clean all the oil around the shaft area. Mark current base and motor tower position. Fig. 2. See XL DC
manual for details.
3.1.2.0. Replac ng the upper base w th the a r bear ng base:
Four screws underneath hold together the upper and lower base. Carefully position the base slightly over
the edge of table to expose one screw at a time. Release all 4 screws using Allen key 6 mm. Then remove
one screw at a time. Remove the upper base with ruby shaft from the lower base. Fig. 5.
Fig. 2. Base with ruby shaft Fig. 3. Base –underneath are 4 screws
Locate the new upper base with air bearing (Fig. 4.) and position it over the lower base ( Fig. 5.). See that
the air indicator is in the front position above the Kuzma label. Insert one screw at a time and fix them
gently. Only after you fit all 4 screws secure them firmly.
Fig. 4. Upper base- air bearing covered Fig. 5. Complete base over the table edge

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3.1.3.0. Base w th f tted a r bear ng
Position base back in the same position as was before.
Fig. 6. Base with air bearing-for now ignore silver filters
NOTE: Before you proceed further with motor tower or platters you need to set up the air supply first!

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4.0.0.0. AIR SUPPLY SET UP:
4.1.0.0. COMPRESSOR:
NOTE: Do not tilt compressor with oil inside!
NOTE: Do not switch on the compressor before filling with oil and connecting the air intake filter. Also
ensure that all air supply tubes are connected.
NOTE: The compressor has a safety valve and overheating protection!
NOTE: Do not position it in a small non ventilated space!
NOTE: The compressor is factory set up to a max pressure of 8 bar (120 psi) higher than
quoted in the Compressor Instruction Manual. (See label at the side of the cover!)
NOTE: Everything is set and checked by Kuzma Ltd. The only item to be added is compressor’s o l
and a r ntake f lter. If the compressor is in an upright position, it can be moved safely.
Open the box and lift up the compressor by the handle. It is a heavy item. Remove the plastic bag. Inside
the box is the instruction manual for the compressor (no need to check it), a bottle with oil, and double
PVC drain bottles. In a small bag inside the compressor housing are the air intake filter and PVC nozzle
with tube for pouring oil into the compressor. Remove the two pieces of cardboard wedged between
compressor head and housing. Fig. .
The compressor should not be transported with oil inside unless you can guarantee that it will be in a
vertical position at all times.
Position the compressor on a hard surface with plenty of air for ventilation! Do not position it in a closed
space, in direct sun or in temperatures below freezing. The compressor must be connected to the mains
voltage.
4.1.1.0. O l
Remove the small plastic cap from the metal input tube. Fig. 8.a. Fix the nozzle with clear tube onto the oil
bottle.
Remove the plastic cup from metal tube. Fig. 9. Put the clear tube from oil bottle into the metal tube at the
side. Gently squeeze all the oil into the compressor. Wipe any spillage of oil. Cover the tube with plastic
cap.
Fig. . Compressor with Double PVC drain bottles

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Fig. 8. Compressor parts- front Fig. 8.a. Compressor-rear
Fig. 9. Oil filling from side of the compressor Fig. 10. Double PVC bottles
At the rear of the compressor is a glass bubble which will show the correct level of oil, which is half the
bubble. ( Correct level is shown only if compressor has not been working for at least an hour) Fig. 8.a
Fix the air intake filter onto the metal tube at the rear of compressor. Fig. 8.a
Locate the double PVC bottles which have three black 'quick fit' fittings on the top. There are three black
tubes (6 mm in diameter), which drain moisture from various parts of the compressor (pressure regulator
filter, cylinder, reservoir, ). Pull them out of the compressor and insert into the top of the Quick fitting on
the bottle. Fig. 10. Position them near the compressor.
When you first turn the compressor ON it will take a little longer to fill the compressor’s reservoir from
zero to 8 bars (4-5 minutes). The compressor must be connected to the air supply tube with the valve closed
otherwise air will freely flow out and compressor can not build up pressure.
NOTE: Oil should last for at least 5 years of normal use and should be replaced when it is very dark -
almost black in colour. Check oil level when the compressor is in the cool-rest position for 2 hours.
NOTE: Check water condensation occasionally, 1-3 months approx in double PVC bottles.
NOTE: For extra details consult original instructions supplied with the compressor.

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4.2.0.0. SILVER FILTERS:
NOTE: Keep the silver filters in an upright position. They might leak otherwise.
NOTE: Keep valve closed between compressor and silver filters until pressure is raised in the
compressor.Fig.13.
NOTE: Keep valve closed between silver filters and turntable.
NOTE: Open the same valve to put pressure into the silver filters. This will seal the drain system.
The silver filters which are positioned near the turntable in their own stands have an automatic drainage
system ( it will collect very little moisture).
Fig. 11. Silver filters- see arrow for airflow
4.2.1.0. Seal ng s lver f lters
The silver filters must be connected with both PVC tubes between compressor and turntable.
Filters are sealed only when air pressure is inside them.
4.3.0.0. AIR TUBE CONNECTIONS:
4.3.1.0. Compressor to s lver f lters
The silver filters should be positioned near the turntable in their own stands.
Choose the longer piece of black tube (21m- with the valve nearer to the compressor) and connect the
compressor output to the silver filters input. Fig. 8.
4.3.2.0. S lver f lters to a r bear ng base
Choose the shorter piece of tube (4m ) and connect the silver filters output to the turntable’s input. Fig. 12.
Fig. 12. Tube from filters to airbearing Fig. 13. Valve in closed position
4.4.0.0. AIR PRESSURE SET UP:
NOTE: All tubes must be connected. Keep both valves on air tubes in the closed position. Fig. 13.

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4.4.1.0. Compressor
Plug the compressor into the mains. The main switch is under the cover on the top. It has two positions.
When the main switch is turned ON, pressure will start to build up (working time) and this will be shown
on the pressure gauge on the left side of the compressor. This will show the air pressure in the reservoir. It
should rise and reach 8-8.5 bars (110-120 psi) in about 4-5 minutes then the compressor will stop (cooling
time). The right hand pressure gauge shows output pressure. It should rise and then show constant
pressure at around 4 bars (60-65 psi). Leave it permanently turned ON. When the air supply is closed at the
turntable’s end valve, the compressor will go on standby.
The knob on top of the pressure regulator is for readjusting the output pressure. To readjust, it must first be
pulled up. Fig. 8. Output pressure is set up in factory to 4 bar.
4.4.1.1. Compressor working cycle when air flow is open:
The working time (heating time) of the compressor is around 90-120 seconds while building up pressure
from 6 to 8 bars. When pressure reaches 8 bars, the compressor switches off (cooling time). When the air
flow is in use, pressure will slowly drop. When the pressure in the compressor drops to 6 bars it will
switch on again and pressure will build up to 8 bars. The cooling time should be at least the same time as
the heating time. This allows the compressor’s head to cool down. It is good to monitor the working cycle
occasionally!
4.4.1.2. If the working time is longer then 3-4 minutes and cooling time shorter than 1 minute, then stop
using the compressor and check maintenance, “troubleshooting“ pages or FAQ ( web)!
First check for leaks. A longer working time will cause the compressor to overheat and can damage it.
NOTE: When you close the air flow on the valve at the turntable end then the compressor will go
on stand- by. But it might switch on every few hours to build up lost pressure. Also you will hear
2-3 second long burst of air leak caused by the timer on “the test switch” releasing moisture from the
compressor every few hours.
NOTE: If you switch off the compressor completely, the air pressure will drop in 12-24 hours. Then
start set up air supply as for the first time.
4.4.2.0. S lver f lters
When full air pressure is reached in the compressor for the first time (the compressor stops working in
about 4-5 minutes) open the valve on the tube before the silver filters and the air pressure will flow into the
silver filters which will seal the automatic drain systems in these filters. Fig.11.
Check if it is sealed properly by listening, there should be no hissing noises.
4.4.3.0. A r bear ng
IMPORTANT:
Do not assemble or operate a r bear ng w thout a r pressure flow!
NOTE: Do not insert subplatter into airbearing without air pressure in the air bearing
Open the valve behind the turntable ( Fig.12& 14.). The front pressure indicator on the base will show a
similar level of air pressure ( 3,5 - 4 bar) as on the right hand pressure indicator on the compressor. Fig .15.
If not, check for leaks (hiss noise) at silver filters or at compressor. Check if the valve on the longer PVC
tube is in the open position.