Saturday, October 24, 2009

backyard blacksmithing

with this post im bouncing around a little chronologically but its too exciting to resist sharing with you the backyard blacksmithing course

enjoy





this is a home made blacksmithing forge. its basic components are a galvanized washtub, a steel pipe, a bellows and a whole crap load of charcoal. in the set up you see in the picture the bellows is a hand turned air blower which gives the set up a nice rustic look which i am a big fan of but you can also use a hair dryer. if you play your cards right everything seen you can put together for about 60 bucks. all the other tools and equipment for operation will bring you up to about 100 plus or minus 20 bucks. in the next few weeks i think you may see a posting on my attempt at duct tapping one of these together...


so.


blacksmith party at my house. on the outside chance that anyone comes across one of those old hand cranked air blowers please let me know. im also taking donations of any worn down wood or metal files you have. more on that in a bit.



these are some examples from the personal collection of our instructor, earthwalks outside expert Howard Schwartz.  from sheaths to handles, all these knives and tools were hand made by Howard using the forge pictured above. 




thats just sweet. that thing will take out small trees.

in case you are interested in a class next year, Howard does yearly courses through earthwalk northwest. for those enrolled in earthwalk's primitive skills class the backyard blacksmithing course is included.




the project: turn one old, rusty file into one elk horn handled bush knife. 




the forge is filled with charcoal and the charcoal fired. here Mark cranks the blower while Howard uses a propane torch to start the coals burning. i suppose one of these would work to and would save the cost of a new propane torch when the old ones run out.




the forge is ready!




the very first step is to break the end of the file off to size the blade. as a general rule a good blade length for an all purpose bush knife is something about as long as your palm is wide.


"but my palm is so narrow"


well, if you have small hands, something proportionate is best.

hold the file up next to your hand and mark the length. sink the file into a vise and cinch it right up along that mark and then WHAM. a solid whack from the forge hammer and you have your knife blank.


after breaking the end off the file, the metal needs to be annealed. as is, the metal is too hard to be worked into shape and it needs to be softened. 





cherry red is the magic color for annealing. the metal has reached the correct temperature when it is glowing this beautiful color. when the metal gets this hot it also loses magnetic attraction so as a final test a magnet is held to the metal while hot to make sure that it isnt sticking to any part of the metal. there should be an even heating so when the metal is reheated later on there wont be any weak points.



when the metal has reached the right temperature it needs to cool. after annealing the blade is kept in an insulating medium to allow it to cool very slowly so it retains the right softness. we used vermiculite in a 5 gallon bucket. after the metal had cooled over night it was time to file the metal in shape. i will say this is definitely the hardest part of the process. if you want the process to go a bit faster you can use a belt sander and a bench grinder but in keeping with the electricity free motif we did this part by hand. as hard as the work was its incredibly satisfying to chip away, by hand all the excess and watch the blade hidden in the file, starting to emerge. 

after a while i had something i felt looked vaguely like a knife blade. or at least close enough to rationalize not doing anymore filing and giving my back and arm a break. 


the grind of a knife blade is the point where the flat of the blade slopes into the edge. there are few different kinds of grinds:hollow, flat, sabre, convex, compound bevel and chisel grind. since this was going to be a small knife, probably for delicate work and because i love to over-challenge myself i decided to try and put a full flat grind on my blade. when you are doing this type of grind you are taking off a lot more metal than with the other types and the transition has to be very smooth from the spine of the blade to the edge. all things considered, for my first time i think i got a pretty nice finish on mine.


this is some examples of the other students' work:






almost as hard and time consuming as the filing is the sanding but also it is twice as rewarding to see the blade start to shine into mirror finish. 

when the blade is as smooth it is going to get (or as smooth as you feel like getting it after your fingers start feeling like they're falling off) it is heated again for the hardening phase. 

the blade edge should be the hardest part of the knife with the metal getting gradually softer toward the spine. to do this the metal is re heated to cherry red/non-magnetic tempurature  and then squelched in an oil bath. it is not submerged all at once. first the blade is held in the oil from the tip to the back of the blade about halfway up the width of the metal. after a few seconds the rest of the blade is then submerged entirely for a complete cooling. make sure your oil pan is aligned north to south and when squelching, the blade point should point north. thats just good juju.

the oil is washed off and the blade is almost done!!! the black finish you see is called scalling. this is oil that has bonded to the metal and is nice for rust resistance or it can be polished off.


at this point the metal is once again hard and brittle and must be tempered. this is a slow heating to a relatively low temperature to soften the metal just enough so that it is functional as a tool but not soft enough to bend of dent easily. for these blades that meant about an hour in the oven at 425.




the handle for these blades were cut sections of elk horn. the horn sections are boiled for about half an hour to soften the inner pith. directly from boiling the bone is shoved on to the end of the blade and left to sit. or, in the case of my knife, a hammer may be called in for particularly stubborn pieces of bone. 


rough draft.


this is my blade with elk handle. it still isnt quite finished though. it needs to be sharpened of course but i also want to do some work on the handle. the handle was shaped by cutting points off the horn and this has left some hard angles and lumps that i want to sand down. after a varnishing this will leave a very nice, smooth finish on the handle. the only bummer is that i have to wait at least a month for the bone to fully set and seal around the blade end befor i can fuss with it. 

the count down begins.




you cant have a knife without a sheath. here sections of leather have been cut from a large piece and left to soak and soften


when the leather is soft and maleable it is formed around the knife(wrapped in cellophane to protect it. and dried out. as the leather dries it molds into shape around the knife. this makes for a snug  fit that the knife will not slip out of.

when fully dry the seem of the sheath is glued and drilled for sewing.


unfortunately, as of this writting none of the sheaths have been finished yet but as that process continues and more knives get the finishing touches we should see some really beautiful pieces of functional art.





Howard says he gets asked "whats so primitive about blacksmithing?"


to which he replies "blacksmithing is more than 4000 years old. how primitive do you want?"


indeed.






5 comments:

  1. very primitive, indeed! for a blower, i'd check with your friends who still have grandparents (like me) who were say, mechanics (like mine) who may have something along these lines. i wouldn't be surprised at all to see one in my grandpa's garage. not that i'd try to get it or even ask for it until he passed away, which i hope is quite a ways away yet. or, check rural antique malls, there are quite a few in snohomish. you'd probably have to shell out some dough, but there you are.

    i can't wait to see your knife and whatever else you make!

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  2. I was going to whittle one from an old toothbrush, but this looks better. Teach me!

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  3. oh man i cant wait to get a set up going. i would love to have people over to try and re-enact the learning experience. i want to do this while the order of procedure is still relatively fresh. ill keep you guys posted....

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  4. Spring steel from a large truck makes the damn best, hardest, toughest, sharpest edge retaining knives I have ever owned n used like my machete, I bang hard as I can w/a sledge on it to split Kiave wood, the bugga is barely flanged out n wont break chit holmes I chop trees as big around as my thigh down using it with technique and a sledge.

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