Fire blueing

Karl · 12-12-2002, 12:27 PM

A few evenings ago I decided to see if I could fire blue something. I set a highly polished repro C96 extractor on the orange-hot burner of an electric range and it immediately started turning the desired peacock blue. Took it off after about 20 seconds and let it cool. The blueing was perfect, only it rubbed right off. Is there an easy way to fire blue small parts? KFS

Heinz · 12-12-2002, 06:45 PM

Karl, the technique is straightforward but tricky. First the part must be absolutely squeeky clean. The heat source must be oxygen poor, fuel rich. A charcoal fire with very low air draft or a gas burner with low air and a "smoky" burn or an acetylene torch, same conditions. Heat the piece slowly and keep it at the blue temperature for at least 10 minutes, without overheating (therin lies the tricky part). Low oxy levels cause the blue to form slowly and bind better to the surface. Immeadiately quench in oil when removing from the heat. I suggest highly polished ten penny nails as a learning tool. You do the polishing so you learn two things.

Heinz

saxman · 12-17-2002, 07:22 PM

And bear in mind that if it's a spring you're working on and you overheat it, it's ruined.

12-12-2002, 12:27 PM	#1
Karl Lifer - Twice Over Lifetime Forum Patron Join Date: Jun 2002 Location: Savannah Posts: 515 Thanks: 0 Thanked 253 Times in 112 Posts	Fire blueing A few evenings ago I decided to see if I could fire blue something. I set a highly polished repro C96 extractor on the orange-hot burner of an electric range and it immediately started turning the desired peacock blue. Took it off after about 20 seconds and let it cool. The blueing was perfect, only it rubbed right off. Is there an easy way to fire blue small parts? KFS

12-17-2002, 07:22 PM	#3
saxman User Join Date: Jun 2002 Posts: 301 Thanks: 0 Thanked 0 Times in 0 Posts	And bear in mind that if it's a spring you're working on and you overheat it, it's ruined. __________________ You can lead 'em to the water, but you can't make 'em drink.

12-12-2002, 06:45 PM	#2
Heinz User Join Date: Jun 2002 Location: Greenville SC Posts: 1,004 Thanks: 377 Thanked 410 Times in 180 Posts	Karl, the technique is straightforward but tricky. First the part must be absolutely squeeky clean. The heat source must be oxygen poor, fuel rich. A charcoal fire with very low air draft or a gas burner with low air and a "smoky" burn or an acetylene torch, same conditions. Heat the piece slowly and keep it at the blue temperature for at least 10 minutes, without overheating (therin lies the tricky part). Low oxy levels cause the blue to form slowly and bind better to the surface. Immeadiately quench in oil when removing from the heat. I suggest highly polished ten penny nails as a learning tool. You do the polishing so you learn two things. Heinz