Borax or laundry detergent are the first ingredient in your homemade concrete cleaner.
Best solution to clean concrete mixer.
Clean baking soda residue by spritzing it.
Use chisel and hammer.
You can tilt the drum a little so that the rubble scrapes the upper edges of the drum.
Answered 3rd may 2017.
Leave it 10 minutes or so maybe give it a few hits on the barrel as it spins.
Your supplies are likely to be a bucket scrub brush and detergent.
Could give this a try.
Hydrogen peroxide or ammonia also work well too.
Often the sharp edges of the spade damage the inner surface of the drum which further adversely affects the cement solution.
Semi dirty outdoor concrete cleaner bleach water 1 8 cup dishwashing detergent.
For a gentle cleaning solution add one half cup of baking soda to 1 gallon of water.
Try putting broken up bricks in there with acid mortar cleaner and water and turn it on let it spin.
Empty the drum of rubble and water.
These products are good for removing basic dirt and some stains.
Mix equal parts baking soda water and salt for highly soiled areas.
When mixed with normal household vinegar and baking soda in a bucket with hot water you get an effective grease cutter and cleaning product.
Put on protective gloves and a breathing mask then apply the solution according to.
Pour some water in the drum along with some old bricks or rubble and leave turning for about 30 minutes.
You should now have a clean cement mixer ready for work again.
Apply a diluted hydrochloric acid solution to the inside of the drum if the cement still refuses to break free.