Ferric chloride crystals

[spareparts]

I have access to ferric chloride in crystalline form. What concentration would I make the solution to use it for etching steel?

 

[delbert ealy]

I have found that 1 lb per gallon of water works great, start with cold water and be careful. let sit for 24 hours and its ready to go.
Thanks,
Del

 

[Stacy E. Apelt - Bladesmith]

FC should be mixed to make a 42 Baume stock solution. You add one pound of crystals to 18 ounces of water to get this strength - one pound to one quart is close enough. Let it sit for a couple days, as Del suggested. Dilute the working solution form this stock . Three parts water to one part stock is what I use ( that is the same as Del's one pound to one gallon).
If you are just making up one gallon, skip the stock solution. If making up a larger batch, one gallon of stock solution is easier to store than four gallons of working solution.

Mix outdoors and don't breath the fumes when it is dissolving. Wearing gloves and a face shield, is a good practice.

 

[Dmitry.M]

And don't store it long, it may degrade even in stock solution.

 

[Stacy E. Apelt - Bladesmith]

Photodegredation may be a problem, but properly stored, the stock solution should have a nine month to one year shelf life. Keeping all chemicals out of sunlight (and thus UV) is always good procedure.