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Welding/Tempering hatchet head

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Question
Hello Ernie,
I have a Greenland-pattern Norlund hatchet head that was found in the remains of a cabin fire.  Not much rust on it, but it was covered with thick black scale which, after scraping off, revealed grey metal underneath...it is fully intact with virtually no pitting. Anyway, is there an easy way (e.g. using only a campfire/bbq and/or regular kitchen oven)to re-temper/ heat-treat this head to make it reasonably serviceable again?  Is there any reason (or point) in me going to the trouble and expense of having it magnafluxed first?
Thanks, Jim

Answer
Magnafluxing is a bit extreme for a hatchet head. Magnafluxing is a dye-penetrant test using UV flourescent dye to show hidden cracks, but the head wasn't pounded on by an elephant, it was annealed. Annealing renders the metal soft. The only part of an axe head that is hard is the edge.
The simplest way to re-harden the steel is to heat the edge up with a torch, but since you don't have an oxy/acetylene torch we will go for another option. You need to achieve 1650 degrees F which is glowing orange, but only for the last inch or two of the blade. You can do this with a camp fire if you can add some form of blower to increase the oxygen going into the fire. A bellows, hair dryer or reversed vacuum cleaner will all provide enough air to boost your heat. You can make a simple forge by digging a hole in the ground and lining it with ashes. Bury a pipe at an angle so the lower end is under the middle of the hole. Use duct tape or something to attach your air blast source to the upper end of the pipe. Try to keep the angle of the pipe pretty low or you can get hot air coming up the pipe melting your hair dryer. Place some smoldering charcoal at the bottom of the hole above the pipe end, then a few pieces of unburnt hardwood and more charcoal. As you start blowing air into the pipe the heat in the fire will climb. Place the edge of the axe head into the heart of the fire. When the edge is glowing hot, pull it out and quench it in a water bucket.
At this point the edge has been made extremely hard. DO not drop it or it can crack. Carefully grind the edge clean without getting it hot. When it is cleaned up place the axe head in your oven and cook at 450 degrees F for 2 hours. At this point your edge should be a purple to blue color and has been tempered and is ready for use.
Have fun.
What you are really doing is building a very basic blacksmithing forge, but charcoal is a very inefficient heat source for sustained smithing as it burns very fast.
Everything I just described I have done, so I know it works.

If you want you really get into this buy Jack Andrew's book "The New Edge Of The Anvil".

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Ernie Leimkuhler

Expertise

Questions about Oxy-Acetylene welding/cutting, MIG, TIG, Flux-core, Stick welding, brazing and soldering, bike frames, air frames, motorcycle frames, structural welding. Also questions about Welding Certifications and Inspections. All questions about fabrication of metals (stainless steel, steel , aluminum, brass, bronze, copper). Basic questions about underwater welding. TIG is my strongest subject.

Experience

Extensive background in most welding fields. 18 years fabrication of metal theatre scenery, 16 years structural steel, 2 years pipe welding, 9 years as a Welding Instructor at South Seattle Community College, and 5.5 years as a Welding Instructor at the Divers Institute of Technology. 16 years Industrial Welding Consultant for fabrication shops in the greater Seattle Area. 11 years Architectural Metal Fabrication. 8 years in Film/TV; SPFX/construction/set-deco/props/. 33 years Blacksmithing and Knifemaking. Currently a Field Welding Inspector for Otto Rosenau and Associates.

Organizations
American Welding Society - Certified Welding Inspector Washington Assoc of Building Officials (WABO) - Special Inspector - Structural and Reinforcing Steel.

Publications
Do a search on google groups for "Ernie Leimkuhler" in the rec.crafts.metalworking and sci.engr.joining.welding groups. http://www.stagesmith.com/ http://www.metalwebnews.com/ Blacksmith's Gazzette - Anvil Making

Education/Credentials
BA Theatre Technology - Purdue University.

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