Same experience. The paste blue by Oxpho works much betterI’ve had much better luck with Oxpho over the years. Bare metal is best for matching consistent color.
Apply each layer with a fresh cotton ball or a clean cotton rag piece, not a brush.Got a Star BM on order and wondering if the cold bluing from Birchwood Casey could be sprayed on with a good quality air Brush? I have used the liquid blue before with a brush and as I recall it went on kind of streaky.
Yes, thanks for the reminder. Or rinse the steel wool in acetone before use. Oil stops and "fixes" the blueing process.....(the steel wool is slightly oily) ....
That is how I got the best finish; I believe that the ferrite in the steel wool helps catalyze the reaction, and using steel wool to apply also opens up the surface of the metal a bit. At least that was my theory as to why it worked so well…Hmm, can you use wool daubers instead of cotton balls?
Got a Star BM on order and wondering if the cold bluing from Birchwood Casey could be sprayed on with a good quality air Brush? I have used the liquid blue before with a brush and as I recall it went on kind of streaky.
I’ve had much better luck with Oxpho over the years.
Apply with the cotton ball as mentioned. Then rinse and dry and card each coat with 0000 super fine steel wool. Wipe with degreaser (the steel wool is slightly oily) and apply the next coat of cold blue. Repeat up to 3 or 4 times. If it's still blotchy after that then it's an issue with the metal.
As mentioned already it's a chemical reaction, not paint or stain or coloring. So put the airbrush down and step away....