Safety : “we” stand in front of spinning steel attached to a motor with the ability to pull us in and flip us all over.
Only safety I would be worried about is the chemical vapors.
That said if you dont feel safe around Hot things dont hot blue.
I have used every cold blue out there. They all work. The degree of how well is subjective and very dependent of Alloy type and environmentals
Brownels products and Casewell are my go to products.
Although I use whats on hand sometimes that Birchwood brand does well also.
The secrete is clean clean clean
Then the light “scrub” o or “carding off” between treatments.
Also never redunk the applicator if applying this way. Light even coats work best.
I have had little luck getting any better finish with immersion , only with small parts.
Old steel can be harder to get a even finish vs fresh clean metal.
I dont like the casewell sealer its more like a clear coat.
I find so far the best “sealer” after I get the parts very clean and all salts removed is a good 24-48 hour soak in old school dark cutting oil. Old smith near me said old dirty engine oil works great. I will use the cutting oil until I run out.
Last thing
Cold blues are not exactly durable so dont expect a lot.
Cold blue is quick and easy and unless your doing many parts I cant see investing in all tanks , chems and the space needed for hot blue or parkerize Especially for longer parts.
I do the rust blue for many things as its even quicker and easier. Many times the pieces are already rusty so just drop them in boiling water then the cutting oil.
The key to rust blueing is getting that very fine even “crust” on the parts. Depending on alloy the rust blue solutions can attach areas more than others.
Only safety I would be worried about is the chemical vapors.
That said if you dont feel safe around Hot things dont hot blue.
I have used every cold blue out there. They all work. The degree of how well is subjective and very dependent of Alloy type and environmentals
Brownels products and Casewell are my go to products.
Although I use whats on hand sometimes that Birchwood brand does well also.
The secrete is clean clean clean
Then the light “scrub” o or “carding off” between treatments.
Also never redunk the applicator if applying this way. Light even coats work best.
I have had little luck getting any better finish with immersion , only with small parts.
Old steel can be harder to get a even finish vs fresh clean metal.
I dont like the casewell sealer its more like a clear coat.
I find so far the best “sealer” after I get the parts very clean and all salts removed is a good 24-48 hour soak in old school dark cutting oil. Old smith near me said old dirty engine oil works great. I will use the cutting oil until I run out.
Last thing
Cold blues are not exactly durable so dont expect a lot.
Cold blue is quick and easy and unless your doing many parts I cant see investing in all tanks , chems and the space needed for hot blue or parkerize Especially for longer parts.
I do the rust blue for many things as its even quicker and easier. Many times the pieces are already rusty so just drop them in boiling water then the cutting oil.
The key to rust blueing is getting that very fine even “crust” on the parts. Depending on alloy the rust blue solutions can attach areas more than others.
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