Operation; Drum Speed; Getting Ready For Mixing - Cleform Gilson 59015C Operator's Manual & Parts Manual

2-OPERATION

DRUM SPEED

The mixer drum should revolve between 20 and 25 R.P.M.'s for best results in
mixing concrete. To obtain this speed using a 1725/1800 R.P.M. electric motor, use a
2" diameter "A" section V-pulley.
If using a 6 to 1 speed reduction 3 H.P. gasoline engine, use a 6 ¼" diameter "A"
section V-pulley.

GETTING READY FOR MIXING

Lay out forms for your concrete floor, patio, driveway, sidewalk, etc.
The quality of concrete is directly related to the quality of the cement paste. The
quality of the paste, in turn, is directly related to the amount of water mixed with the
cement. For a given amount of cement, as the amount of mixing water is reduced, the
strength of the paste increases, making the concrete stronger and more durable.
The proportions by weight given in Table 1 can be used as a starting point to make 1
m3
cu. Ft. (0.028 ) of strong, durable concrete. The proportions given in Table 2 are
volumetric; 1 bag of cement is equal to 1 cu. ft. (0.28
(42.6 kg). The Canadian bag of cement has a net mass of 40 kg.
The proportions are only a guide and may need adjustments to give a workable mix
with locally available aggregates.
Table 1. Proportions by Weight to Make 1 Cu. Ft. of Concrete
M a x i m u m -
size course C e m e n t
aggregate in.
l b
3/8 2 9
1/2 2 7
3/4 2 5
1 2 4
1 1/2 2 3
*If crushed stone is used, decrease coarse aggregate by 3 lbs and increase sand by 3 lbs.
Metric conversion: 1 lb = 0.121 kg
1 i n . = 2 5 m m
Table 2. Proportions by Volume*
M a x i m u m -
size course
C e m e n t
aggregate in.
l b
3/8 1
1/2 1
3/4 1
1
1
1
1 1/2
*The combined volume is approximately 2/3 of the sum of the original bulk volumes.
Portland Cement Association 1980
Air-entrained concrete
Course
S a n d aggregate W a t e r
l b l b l b
5 3 4 6 1 0
4 6 5 5 1 0
4 2 6 5 1 0
3 9 7 0 9
3 8 7 5 9
10 lbs = 4.54 kg
1 Cu. Ft. = 0.028 m
Air-entrained concrete
Course
S a n d aggregate W a t e r
l b l b l b
2 1/4 1 1/2 1/2
2 1/4 2 1/2
2 1/4 2 1/2 1/2
2 1/4 2 3/4 1/2
2 1/4 3 1/2
3
m3
) and weighs 94 lbs.
Concrete without air
Course
C e m e n t S a n d aggregate W a t e r
l b l b
2 9 5 9
2 7 5 3
2 5 4 7
2 4 4 5
2 3 4 3
3
Concrete without air
Course
C e m e n t S a n d aggregate W a t e r
l b l b
1 2 1/2 1 1/2
1 2 1/2
1 2 1/2 2 1/2
1 2 1/2 2 3/4
1 2 1/2
l b l b
4 6 1 1
5 5 1 1
6 5 1 0
7 0 1 0
7 5 9
l b l b
1/2
2 1/2
1/2
1/2
3 1/2