Blade Coffee Bean Grinders

The main advantage of blade coffee bean grinders is the cost. If you want a cheap coffee grinder you will probably get a blade coffee grinder. These electric coffee grinders are simple to use and maintain but they do have some drawbacks and they are not suitable for every brewing method. Here I will explain to you what the problems with blade grinders are and how you can work around them.

Blade grinders have a grinding chamber with a metal blade that spins very quickly. The blade chops the coffee beans repeatedly until the grinder is turned off. The longer you let the grinder run the finer will the coffee be. So you control the coarseness of the coffee by how long you grind it.

Drawbacks of blade coffee bean grinders

There are some drawbacks that you should think about before buying a blade grinder.

First, the blade grinders do not grind the coffee uniformly. The coffee will contain grains of various different sizes ranging from coffee dust to large chunks of coffee beans. This uneven grind is the main problem with the blade grinders. I will talk about it more in a minute.
Another issue is that they heat up the coffee while grinding it. That can damage the flavor of the coffee. The more the coffee heats up during the grinding the more flavor is lost.
Some blade coffee grinders also build-up a lot of static electricity. When the coffee particles are charged with static they will try to attach to almost anything that is around (plastic in particular). This can be quite messy.
Some blade grinders can be very noisy.

Uneven grind - why is this a problem?

The ever present coffee dust is the trouble-maker. It can either get through your coffee filter or it can clog the filter. You can end up either with some sediment in your coffee or with a big mess to clean up. If you are using paper filters then this should not be a problem because the paper filter can cope with the dust fairly well. You can minimize the sediment and the risk of clogging the filter by following the tips below.

Another problem with the uneven grind is that it will actually impact the coffee taste. The small grains will over extract and the large chunks will under extract. So you will not get the best flavor out of your coffee beans. Having said that, you will still be much better off than using pre-ground coffee.

Tips for using the blade coffee bean grinder

Follow these two tips and you will make the ground coffee far more uniform than if you leave the grinder running continuously. The coffee will also heat up much less and it will be less static.

Grind the coffee in short bursts - let the grinder run only for a couple of seconds at a time.
Shake the grinder after each burst.

If you have a problem with a lot of static charge in the coffee grains:

Wait for several minutes after you have finished grinding and only then open the lid. That allows some of the static charge to dissipate.
You can also moisten slightly a few coffee beans before you do the grinding. Static builds up easier when the humidity is low, so adding a tiny bit of moisture will reduce the static charge.
To avoid the ground coffee flying all over the place, tap on the lid before you open the grinder. Then remove the lid very slowly.

When to use the blade grinder

Blade coffee bean grinder is best suited for a drip coffee maker that uses paper filters. The blade grinder also works reasonably well with a French press, a Moka pot, Toddy coffee maker or a drip coffee maker with a metallic filter. Just be prepared for some sediment in your cup of coffee.

When it comes to espresso machines, the blade coffee grinder is definitely a bad idea. Not only will it make an awful espresso shot, it can actually clog the filter and potentially even damage the espresso machine. For an espresso machine you should get the best burr coffee grinder that you can afford.