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3. Setting the deposit size
Test different time and air pressure, to get the wanted dispensing volumes
.
- For medium to high viscosity glue, use a tapered needle.
- For low viscosity glue, use a metal needle with a smaller gauge.
- For micro dispensing volumes, select low pressure (0~30psi).
Note:
First select the suitable pressure, from low to high, adjusting slowly.
1. Depending on the viscosity, adjust the Air pressure:
- Aqueous glue – Pressure 0.1 ~ 1.0 bar (1.5~15 psi)
- Low viscosity glue – Pressure 1.5~2.0 bar(22~30 psi)
- Medium viscosity glue – Pressure 2.0~3.0 bar(30~45 psi)
- High viscosity glue – Pressure 3.0~5.0 bar(45~75 psi)
2. For low viscosity glue you should open the vacuum switch to prevent dripping.
3. Remove the air in the glue and piston.
4. How to Use the Vacuum Control
The vacuum control allows low viscosity liquids, even water, to be consistently dispensed without dripping
between cycles. The vacuum exerts a negative pressure on the liquid in the barrel and prevents dripping.
For these tests, you will use the test barrel with the clear fluid.
1.
While holding the barrel upright in one hand, remove the
orange end cap and insert the piston. Allow an air gap as
shown.
2.
Attach the barrel to the adapter. Snap the safety clip tightly
closed to prevent any dripping or bubbling. Remove the tip
cap and attach the tip.
3.
Set air pressure and the time.
4.
Press the “Man” mode.
5.
With the barrel pointing downward over a container, unsnap
the safety clip. Then press the foot pedal to fill the tip.
6.
If a drop begins to form at the end of the tip, slowly turn the vacuum control knob counterclockwise
to stop the drop from growing. Wipe the tip and adjust vacuum as necessary. Normally, only 1 to 2
psi of vacuum pressure is necessary.
7.
Press the “Auto” button to return to the preset dispenses time.
8.
Take the barrel and place the tip on the test sheet. Press the foot pedal. Check the dot size. Increase
or decrease by adjusting pressure or time.
