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Heat Treating / Blade Making

Blades Heat Treated

How to Heat Treat
Tool Steel Blades

You can use a large can, clay flower pot or rear brake drum from a car or truck to hold the charcoal..
You will want some type of metal pipe and device to blow air into the bottom of the fire.. A hair dryer or vacuum like I use set up to blow into a piece of fence post of aluminum foil shaped like a tube.. You can use a hole in the ground or a stack of bricks or rocks..

You will lay down your tool steel on top of the coal till it is close to yellow.. The color you want is cherry red almost yellow.. Once it is at the correct temperature it will no longer be magnetic this phenomena is called The Currie Point you will then want to place the hot steel into a very warm can of oil about 150 to 200 F. so not to shock hot steel and crack it, temper immediately after.. I use Peanut but most any oil will work and I find cooking oils to be the least smelly..
After the part cools you need to clean and polish the steel.. You will then need to temper (make it softer) the steel as it will be so hard if dropped or struck it could break like glass does.. I find my kitchen oven to work best.. Heat oven to 350 and check steel after a an hour if you see the steel has a light blond or straw color it is good you do not want it to turn dark brown and if it tempers that much it will be to soft to use as a cutting blade..

 

I have worked as a machinist for over 30+ years
and have learned a lot about steel and heat treating but just in the last few months have I learned a lot about how to heat treat in my backyard..

Most of the info I picked up on building a forge was from
The ABYMC (Association of
Backyard Metal casters)
in particular
Backyard Metal casting and their page on how to make a Refractory (Heat Proof (Insulation)

Most of the pages on heat treating I found just use a open coal fire or a elaborate electric furnaces, so I decided to go with a metal melting style furnace, instead of a open style hearth.

 

McMaster-Carr 20Gal Trash Can

This is pictorial of how I built my McMaster-Carr 20Gal Trash Can Furnace..

Above you see the 3" thick refractory and loading door.. Instead of a door I could have made a fire brick out of the refractory that fits the shape of the door opening.

Heat Treating Oven Here you see the cover to help keep the heat in, I was hoping I could place the steel on a fire brick about the fire box but it doesn't get hot enough and must go in the coals ..
This is what the furnace looks like when its not in use, I keep the cover on it as if the refractory gets wet the heat of a fire may cause it to blow out the refractory from the side of the can.. Heat Treating Oven
Heat Treating Oven Here is a picture of the furnace in operation.. It has a 2" fence pipe going through the bottom back and I use a vacuum to blow air through so rubble stones and into the fire box.. On the right is a 1Gal. can with peanut oil I use for quench 0-1 tool steel.
View of some steel inside the fire box... Coal fires get to about 2000 degrees the 0-1 needs to reach about 1500* to reach it's critical temperature when it is quenched in oil.. Heat Treating Oven
Heat Treating Oven Here is an out of focus picture of roaring fire.. I use just plain BBQ Charcoal and add some gas for the lawn mower to start the fire.. Please be carefully starting the fire.. I do this with the top off so it has a lot a air to start and I do not have the vacuum on when I first start it..
Few blades and some marking knives after they where quenched in the oil.. You can see the smoke from the peanut oil can, after several blades go through the oil gets so hot it will catch on fire.. I leave the blades in the oil about 1 min. then lay then on the ground.. This helps stop the oil from getting super heated as fast as just leaving them in the oil to cool.. If the oil does catch fire I just place a brick over the opening and snuff the fire out.. Heat Treated Blades

 

You can find the Recipe for the Refractory Mix At Back Yard Metal Casters..

Also a link to the Two Buck Furnace this is what gave be the idea to make my furnace.. I used two 5gal. plastic pails for the mold inside.. One pail I just used the plastic from the sides with some masking tape to make a smaller size mold for the fire box under the full size I used for upper part of the furnace..

For info on Heat Treating Steel I really like Terry Primos' Web site
I also found some helpful info at The Knife Network's Online WorkShops

I have a lot more info written down on a yellow pad I just need time to format it and add it to this page..

MKIII Sharpening Machine I have almost finished building a LV style MKII \ Lap Sharp sharpening system.. I call it my MK III, the total cost so far is about $70, I used a 1/3HP GE motor and some Pillow Blocks, a Jet Lathe 8" Face Plate with a 5/8" shaft and some pulleys.. So far I have only flatten blade backs and it works super. I have clad the plywood with a sheet of SS metal and will build or buy a tool rest soon.. You can view the images and description..

Hand Planes 101This is a collection of pages I have put together with all the methods I use in tuning and refinishing hand planes for my self and as a service I provided to woodworking forum members on the internet ..I am no longer refinishing hand planes but I am trying to explain with pictures and text the methods I use..

Back Yard Heat Treating Oven had started making blades for hand planes and marking knives and needed a klim to do the heat treating.. This page explains where and how I made my oven and how to heat and harden 0-1 Tool Steel.
Most of the info on the oven came from Back Yard Metal Caster really great site if you want to build a oven of start casting metals..

Machine Shop Lathe Service have started making hardware parts for infill and woodworking tools.. So far I have a hand full of customers I have made items for.. These vary from First Class Norris Style Depth Adjusters to Lever Cap Screws to Frame Saw Adjusting Screws to Back Saw Screws.. Check out my Machine Shop page to view some of the items I have made already.. I have planes to also start making small hand tools..

Got Wood? I have a few places I found for great wood deals, Justin Holden's www.exoticwoodsoftheworld.com
is one of them.. I have bought 669 BF of Okoume (African Mahogany) for $669 + $303 shipping and its SUPER Quality.. So check his pallet loads or single boards at his eBay store and be aware to read listing well as some of the wood he lists has checking problems and some is FAS..

Your Cutting Edge A Collection of pages on different methods of sharpening plane irons, chisels and various other cutting tools.. The Main Page contains methods include Bench Stoned, Scary Sharp Method that is using sand paper glued to a flat surface like glass of granite, Power Sharpening page explains use of motor driven sharpening tools, Sharpening Jigs and Gauges as well as Super Charging, what I call adding loose abrasive grit to sandpaper or bench stone to renew the cutting action,Getting Started page has a short list of tools I think is necessary for sharpening.

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