Improved method of cold blue touch up.

[His lordship.]

For years I have used Cold blue for touch up on my guns, followed the instructions which usually said to rinse with water after applying and oil to protect the metal within a minute after chemical application .  I had used Birchwood Casey previously and went to the Brownells T-4 for better quality about 3 years ago.
 
Often times the blue would rub off after being wiped down with oil after one or two trips to the range, some members have mentioned using heat during application, I have not done that yet.  My local library has numerous old gun books and read something on gunsmithing that I never heard before.  They said to let the cold blue "cure" by leaving it alone after application for 24-36 hours and then apply oil.  I have done this on 2 projects for 24 hours and it seems to be more durable.  Only time will tell, has anyone used the "cure" time on their cold blue projects?  And did it seem to hold up better?
 
Thanks. 
 

[gunnut69]

Cold blues AND hot blues should be cured after application and before use. I use OcphoBlue from Brownells. It works thru a little oil and is much tougher after curing. The T-4 is used with a different process. The Birchwood Casey product I'm familiar with is mo9re of a metal stain than a cold parkerizing type material like OxphoBlue. I use heat in the OB application process, by heating the metal to be blued to a fairly high heat (not enough to sizzle the OB liquid). Keep the surface wet until it stops darkening. Then gently wipe dry and when DRY, burnish with 00/000 steel wool. This step polishes the blued steel and clears the surface for further darkening. After rust si greatly rduced with the OxphoBlue product but after bluing with any product I oil without rubbing and allow a day or 2 before use or assembly. If just touching up a spot usually disaseembly is not needed so I simply oil..