(a) Have the following items on hand to complete the calibration.
(1) 36 bags type 1 (normal) Portland cement (minimum quantity).
(2) Stopwatch (accurate in seconds).
(3) Six clean, dry, 3 cu ft (.084 m3) containers
(4) Scale -0-250 lbs (0-113.5 kg) accurate to 1 lb (.454 kg).
(b) Empty sand and stone bins.
(c) Remove mixing trough assembly. (Notify organizational maintenance).
(d) Clean sand and stone bins thoroughly. Sweep and brush until all aggregates are removed.
(e) Clean conveyor belt thoroughly. Be sure chain is clean.
(f) Check operation of four vibrators. (Check by feel of hand against side of bin close to vibrator).
(g) Clean meter-feeder wheel thoroughly.
(h) Check that spring tine arms move three-fourths to one inch (1.9 to 2 5 cm) against spring tension (notify
(i) Check cement bin auger for bent or missing fingers (notify direct support maintenance).
(j) Check meter register operation.
Be sure there is no loose play in cable (notify organizational
(k) Using auxiliary cement bin or quick-loading hopper, add 3 to 5 in. (8 to 13 cm) of cement to cement bin
(I) Actuate air pads with short, sharp blasts (para 2-12). Check for gentle puffs of cement. Torn cloths will
cause blasts of air If no puffs are seen, cloths are clogged (notify organizational maintenance).
(m) Using auxiliary cement bin or quick loading hopper, fill the cement bin with type 1 (normal) Portland
cement. Bin must have at least 36 bags of cement in it.
(n) Remove auxiliary cement bin or quick loading hopper and inspect air breather hole (fig.2-12). Hole (1)
must be free of all dust or dirt. Clean, if required, using a stiff wire.
(o) Be sure ground straps (2) and (3) are in good condition and touching ground. Avoid calibrating on
wooden floors since ground will not be established.