tern opens as adjustment is made (FIG. 12).

FIG. 12: Opening Spray Pattern

5.Fine tune spray pattern:

a.After you back out adjustment screw, make fine adjustments (1/8 turns or less in either direction as required) to obtain pattern shown in FIG. 13. Moving the screw out beyond this point may cause the pattern to split, as shown in FIG. 14.

FIG. 13: Desired Pattern

Spray Pattern Adjustment

FIG. 14: Split Pattern

b.If full-round pattern cannot be achieved, ensure that material temperature and spray pressure are correct. If pattern remains closed upon reaching maxi- mum specified number of turns out from point of valving, material temperature is too low

c.If pattern splits or has hollow center, even with the adjustment screw at mini- mum number of turns from point of valv- ing, material temperature is too high. Refer to FIG. 12.

d.After reaching satisfactory spray pat- tern, note temperatures at proportioner and hose, and position of notch on the adjustment screw. As spraying pro- ceeds, pattern may occasionally streak or change. If this happens, inspect chamber tip and remove any build-up of solid foam with wooden stick or brass wire brush.

311320H

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Image 15
Graco 311320H important safety instructions Tern opens as adjustment is made FIG