Is Etching Worth Your Time?

Etching your titanium before anodizing will better prepare the surface of your titanium for anodizing. Using an etch will increase the potential vibrancy and the voltage you can anodize your titanium to. We etch all our titanium before anodizing, and it’s how we are able to consistently hit high voltage colors, like green.

Example of some titanium parts we etched before anodizing

Gather The Parts

We use a 1L mix for our in house anodizing. If you need a larger batch, you can double or triple our provided formula. We store the etch inside a 1L polypropylene (marked PP on the bottom of the container) mixing cup , that is sitting inside a crock pot. We’ll use the crock pot to heat the acid without having to directly interact with the acid.

Precautions And Safety

  • Rubber gloves
  • Safety goggles
  • Fume hood, or respirator capable of blocking vapors
  • If splashed on skin rinse off with regular water
  • Do not store acid in glass or metal containers, plastic only
  • Add acid to water. Never water into acid. This will reduce the chance of splashing acid.

Things You'll Need

  • Suitable container for the acid. We recommend something with a lid – Here is one of many examples. You can acquire suitable containers at your local hardware store as well. You can also store the acid inside a jug for long term storage. Here is an example.
  • Crock pot or some other way to heat the acid if you plan on using the acid hot. We recommend using it hot. Here
  • A scale designed for small measurements. Here is the one we use.

Ingredients You'll Need For: 1L (1.056qt)

  1. 114g (4.02oz) of APS (Ammonium Persulfate) – Here
  2. 21g (0.74oz) of NaF (Sodium Fluoride) – Here
  3. 1L (33.81oz) of distilled water – Here, or can be acquired at a local supermarket. Walmart typically has some.

Mix Instructions

  1. Add 1L of distilled water to a suitable container with a lid. This can be a jug or the container you’ll use for etching.
  2. Weigh out 114g of APS, and 21g of NaF, then add to the distilled water.
  3. Close container with lid or cap and shake vigorously, then leave overnight. If you plan on using it sooner, shake it again right before use.
  4. Here, or can be acquired at a local supermarket. Walmart typically has some.

In Use

  1. Place a suitable wide mouth container inside your crock pot. Unless the acid is already stored inside one.
  2. Heat the acid to 130 – 150ºF or until you see small bubbles.
  3. Swirl your titanium parts in the acid for 8 – 12 seconds. You should see the part react with the acid pretty fast. If nothing happens, the acid is to cold and you will need to leave your part in longer.
  4. Remove your part from acid and rinse in distilled water. We use a separate container and we will submerge our freshly etched parts in it.
  5. Anodize your part immediately or store in some distilled water so the part does not reform its natural oxide layer.