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Note (b)
This type of reading, with both floats equally low and pressures correct can be due to:
Restricted nozzle holes or undersized air nipple or dirty air nipple or too much air
pressure.
Restricted mixing block holes.
Pressure gauges reading too high or extra-long hose lengths being used.
In all cases the pistol will be quite usable if flowmeter readings are within 15% of
recommended readings. Spray throughput may be slightly reduced.
Note (c)
Readings of this type show an incorrect ratio of oxygen/gas mixture. With standard
type nozzle assemblies, i.e. 1015, 1020, 1010 etc., the imbalance can be easily
corrected by raising or lowering the oxygen pressure by a small amount. With other
nozzle assembly types, the mixing block holes should be checked for restrictions.
Note (d)
Procedure for Fine Spray
Set the flowmeter markers to: Gas 1.5, Oxygen 1.5
Set air to 50 psi, propane to 20-30 psi, oxygen to 34-45 psi
(Note: The higher gas and oxygen rates give slightly higher spray rates, however this does
lead to hotter deposits).
Open valve and check that gas float is spinning:
(A vertical tube and slow valve opening may be needed) (If gas float are not spinning freely,
then reading will be approximately 0.2 divisions too high)
Adjust oxygen pressure to bring to top of the oxygen float to the same position (relative
to the top of the gas float is to the gas marker).
Note: If the tops of the floats are higher than 2.0 on the tube scale then lighting may
be difficult.
NB: If the top of either float is lower than 1.5 then check mixing block for restricted gas holes.
Light the Pistol and start the Wire Drive.
If gas float is spinning freely, adjust oxygen pressure to position top of
oxygen float to same relative position as top of gas float.
Adjust wire speed if necessary
Close valve and stop wire
NB: This pistol may be re-lit and used without further as adjustments through an occasional
check on the flowmeter reading, while spraying, is advisable.
NOTE: Excessively HIGH or LOW flows may indicate leaks or blockages in the Supply
lines to the pistol.
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