Track of the Wolf browning solution. It was my first time browning anything so it was a little trial and error to start. Wear gloves and eye protection. The solution is an acid. Baking soda will neutralize it.
I cleaned and sanded all the metal. Degrease everything well with acetone (it dries immediately). Doing a thorough job degreasing is very important for a good outcome. Put a coat of browning solution on with a cotton ball. Q Tip in hard to get areas. An hour later put another light coat on. Put even light coats on. Let it sit for at least twelve hours. I initially tried using 0000 steel wool to remove the surface oxidation but got a little over zealous and removed too much. If you use the 0000 steel wool be gentle and only take the surface oxidation off. I ended up using paper towel to remove the oxidation. Worked fine and didn't remove too much. Clean oxidation residue off the parts and repeat the cotton ball and solution steps. If you run into a spot the solution isn't working you may have not gotten it degreased correctly there. Use the acetone again. It will not hurt the browning process and will remove the oily spot ( I had a spot like that) It will look a little splotchy to start but evens out with repeated treatments. Keep repeating until you get a uniform desired color. Humidity helps the solution work faster. Make sure the humidity is getting to all the parts evenly. If using a humidifier hang the or suspend the parts so all surfaces are exposed helps. After I got the color I wanted I neutralized the solution. I washed all the parts in baking soda and hot water. Neutralizes the browning solution. Stops the rusting process. I then dried the parts by hand using a soft cloth and then heat gun. I then warmed all the parts to about 140 degrees with the heat gun. I applied a coat of 5W30 motor oil to all the parts while warm and let them hang for a couple of days (motor oil isn't a penetrating oil). Wipe off the oil and assemble.