Concrete doesn't need a lot of equipment to be mixed or poured, but the right tools will make the job much easier.
Here's a list of the tools and supplies I'm using in this class:
Personal Protective Equipment
The mighty bucket and trowel are the cornerstone of mixing concrete. For larger jobs most people use a wheelbarrow and a shovel, which is just a scaled up version of a bucket and trowel. You'll want a sturdy plastic bucket which has enough height to prevent spillage while mixing. Plastic buckets like this are very inexpensive, so pick up a few different sizes so you have choice when working with different sized projects.
The trowel is a flattened shovel used to float on top of concrete after pouring to help smooth it out. It's also the concrete multi-tool which you can scoop, mix, and use as a spatula. It's your go-to tool in the world of concrete.
Variable Speed Grinder
To grind and polish concrete you'll need special diamond polishing pads, and a tool to mount them on. Typically professionals use a special grinder that can drip water on the work while grinding, which will suppress the dust. However, wet grinders are very expensive.
A variable speed grinder will have a dial somewhere on the tool that can change the speed of the angled wheel, allowing slow rotations which will create less dust and give a more even finish.
Grinding / Polishing Discs
Since concrete is very hard we'll need an even harder material to grind and polish. Like sandpaper, diamond polishing pads come in different levels coarseness, from rough to smooth. This kit has doubles of the coarse grades of polishing discs, then steps up to very fine grade for a mirror finish.
These pads are interchangeable, so moving up a grade is really simple. Just like sanding wood, start with the coarsest grit and work your way up to the finer grits.
For most grinding and smoothing in concrete you will need the grinder mentioned above. However, you can also use a variable speed random orbital sander to knock off any flashing and sharp edges.
Since concrete is so tough and this tool really isn't designed for stone work, I'd only use 60-80 grit sandpaper.
The two largest concerns when working with concrete are dust and the alkalinity of Portland cement. First we'll look at dust and the protective equipment you can wear to limit your exposure.
Personal protective equipment (PPE) for working with concrete are rubber gloves, cartridge dust mask, sealed eye protection, and a face shield for good measure. This is totally overboard for most applications. However, if you consider that Portland cement contains crystalline silica dust which when inhaled can cause silicosis, a serious and incurable respiratory disease, then the safety measures included here make sense.
Make sure your cartridge mask has dust cartridges that are NIOSH (National Institute of Occupational Safety and Health) approved, and is snugly fitted to your face.
Aside from the usual (PPE) there's an added caution to working with concrete, it can cause burns. Most people are familiar with what acid is, and that it can cause burns. On the other end of the scale from acid is base, and just like acid can damage your skin so can basic chemicals.
Portland Cement is very basic (or, alkaline - the opposite of acidic), meaning it's caustic and can burn your skin. If tap water is neutral at a pH of 7, Portland Cement has a pH of 12 to 13. In addition to high alkalinity, the hydration reaction that cement goes under as it cures is aiming to draw out moisture - in this case, your skin.
In most cases you're likely to have concrete on your hands. If left untreated it will feel like the worst dry skin sensation you've ever had. Even brief exposure to concrete can have effects hours later, so wear gloves and be sure to treat any areas by neutralizing the concrete.
How To Neutralize Concrete
To neutralize a base you need to add anything more acidic. Before you go dumping battery acid all over your hands there's a much easier way to combat an alkaline substance: vinegar.
It's a good idea to wash any affected area with water first, as this will begin to bring the pH levels down (pH 7 is more neutral than pH 12), this can be easily done with a hose or a bucket of water.
Flush area with plenty of water to remove all traces of cement as soon as possible - the longer you wait to remove alkaline from the skin the worse the impact to your skin. When you're sure all cement has been removed from your hands and anywhere else you can move on to raising the acidity even more to neutralize any lingering alkalinity.
Pour common white vinegar over the area to bring the pH up even more (vinegar pH is around 2.5-3) and fully neutralize any lingering alkalinity. Make sure yo rub your hands together to really get good coverage.
After, unless you want to smell all vinegary for the rest of the day, it's a good idea to rinse your hands once again with water to neutralize the vinegar acid and bring the pH back to neutral.
Share a photo of your finished project with the class!
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