Suggestions: How to buy the right Cement Mixers
When calculating what your cement mixer can produce you must understand how
cement is being batched. When making cement in your cement mixer you start off
with one bag (usually 80 lbs.) of Portland cement. Next you add sand gravel
and water to your mixture in the cement mixer. The breakdown of this combination
is as follows:
1 bag of Portland cement (80 lbs)
Sand (180 lbs)
Gravel/P-Gravel (240 lbs)
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= 500 lbs of material in the cement mixer
Please note: 1 bag of Portland cement is equal to about 6 (80 lb) bags of Pre-mix
cement for your cement mixer (Pre-mix is a mixture of Portland cement, sand
and gravel to which you only add water to in your cement mixer)
When buying a cement mixer you must look at what the overall cubic feet of
the cement mixer is. Most manufacturers will say that the total volume of their
cement mixer or drum capacity is 9 cubic feet. This 9 cubic feet is really 6
cubic feet of batch output for the cement mixer (remember cement mixers do not
mix straight up and down they mix on an angle which means the entire drum is
not used all at once, only about 2/3 of the cement mixer).
Another way of looking at a cement mixer is to look at the total weight the
cement mixer can actually mix in one batch. If a cement mixer rates its capacity
at 250 lbs of cement, then you must remember that 1 bag of Portland cement requires
500 lbs of material. This means that the cement mixer will be able to handle
� a bag (80 lb) of Portland cement plus sand, gravel and water in the cement
mixer.
BE CAREFUL: Some people get confused between Portland cement and Pre-Mix and
some manufacturers will base batch capacity on Pre-Mix for their cement mixer
since a lot of consumers will purchase Pre-Mix. Pre-Mix is more efficient for
almost all jobsite applications.
So you must ask or realize that if the cement mixer has a rating of 1-2 bags
and it is only a 5 cubic foot cement mixer it is based off of pre-mix bags.
Because 2 bags of regular cement or (Portland cement) would require a 1000 lbs
of mixing material to complete the job and any towable cement mixers cannot
handle that, only in industrial sized batch plant.
If you have further questions about cement mixers, or would like to purchase
a cement mixer you can call one of our cement mixer specialists and they will
be happy to assist you.
Concrete Mixing Tips:
Volumes & Weights of Materials
* 1 Bag of Cement = 88 lbs. *
1 Cu ft. Sand/Gravel = 85-100 lbs.
* 1 Cu. ft. Plain Concrete = 140-150 lbs.
* 1 Cu. ft. Water = 62-65 lbs.
* 1 Gallon of Water = 8.33 lbs.
* 1 Cu. Yard = 27 cu.ft.
CONVERSION CHARTS
* Average maximum load = 200 lbs.
* 2 cu. ft. = 6 sq. ft. 4" thick
* 2 cu. ft. = 8 sq. ft. 3" thick
* 1 yard = 27 cu. ft.
* 1 yard = 80 sq. ft. 4" thick
* 1 yard = 108 sq. ft. 3" thick
* 1 80 lb. bag = 2/3 cu. ft.
* 1 80 lb. bag per fence post
How to Mix Sand & Gravel
* Use an 8-1/2 x 12" square point shovel.
* Portland cement, gravel or round stone and masonry sand.
* Start mixer in motion.
* Put in 2 gallons water.
* Add 6 shovels full of gravel or round stone.
* Add 2 shovels full of Portland cement. Slowly add 4 shovels full masonry sand
* NOTE: WATER WILL VARY ACCORDING TO MOISTURE CONTENT OF SAND & GRAVEL.
How To Mix Concrete
* You will need approximately 2-1/2 gallons water.
* Two 80 pound bags pre-mix concrete.
* Start mixer in motion.
* Put in 2 gallons of water.
* Add one 80 pound bag of pre-mix concrete
* NOTE: MIXTURE WILL BE VERY SLOPPY
* Slowly add 2nd bag of 80 pound pre-mix concrete.
* Add 1/2 gallon water slowly to obtain desired thickness.