Are aluminum grinders safe for me?
This is a complicated question. Generally speaking, with the form of aluminum grinders today, they are not safe for you. This is a bold statement from a grinder manufacturer that actually chooses to incorporate aluminum in their products. Make no mistake—our products are different than any other grinder out there, as the main parts are buffered by a plastic buffering ring.
Aluminum is a soft material and very common in the making of cannabis grinders. Take a close look at the bottom of your grinder. You should be able to see the tool path markings, such as those shown in the image below.
COLORED ALUMINUM HERB GRINDERS
Under the Federal Food, Drug, and Cosmetic Act (Chapter VII, section 721), color additives, except for coal tar hair dyes, are subject to FDA approval before they may be used in food, drugs, or cosmetics, or in medical devices that come in contact with the bodies of people or animals for a significant period of time. The following resources are related to the use of color additives in FDA-regulated products.
ANODIZED ALUMINUM HERB GRINDERS
Anodized aluminum herb grinders are very common, and we’ve gotten used to seeing them around. However, this would not be the case if the market was not overlooked, since adding coloring pigments disqualifies the coating from food contact.
There are 2 types of anodizing processes. Here are the differences:
Soft (regular) anodizing builds an organic layer above the material surface. It is considered soft because it doesn't harden the aluminum surface. If your product color can be peeled off easily, it means that it has been soft anodized.
Hard anodizing builds equally above and below the material surface. This hardens the raw material surface and presents very good wear resistance.
ALUMINUM GRINDERS - WHAT TO AVOID
WEAR, WEAR, WEAR!!! Aluminum grinders tend to wear out rapidly. This happens because aluminum is considered a soft metal. But, the wear is more related to the chosen materials in assembly; the friction between identical materials is higher compared to a hard material and soft material. As the grinder builds up some resin, it will be harder to operate. This means that friction is being built up, and as a result, little by little, the material starts to degrade, and little pores are created on the surface of the grinder. If you are using an aluminum grinder, the word "shaving" represents the above-mentioned process.
You may say, "Yes, but it can be cleaned!" This is true, but not really effective, as the little pores that were created earlier multiply the friction rate. For good friction, a smooth surface is required.
If your grinder is colored, you can perform a simple test on your own. Simply take a sharp tool and (lightly) scratch the grinder’s surface. If it peels off a thin layer quite easily, then it is colored. If it takes a little more effort and the result shows a very thin color mixed with some aluminum, then it is anodized. If this test doesn't provide any evidence, then you probably didn't apply enough pressure, or your grinder was coated using a hard anodizing process, which is less likely.