Wednesday, July 25, 2012

How To: Silver Brazing Threads To The End Of A Steel Knife Tang.

TANG EXTENSION

#1. File a “V” notch in the end of the tang with a triangular file and file or grind one end of the threaded piece to match as perfectly as possible. Make sure the area and surfaces to be joined are clean, and free of scale and oxidation.

#2. Use hard grade/high temp., silver solder granules. The granules are made by fluxing pieces cut from sheet or wire solder and then heating them with a torch until they melt and pull into tiny spheres. The granules can then be transported with a stainless steel soldering pick. This is done by melting flux on the tip of the pick and the granule simultaneously and using the tackiness of the flux to hold the granule.

#3. Flux the joint and position the granules.

#4. Heat the steel, (tang and threads), evenly with a torch until the solder flows into the joint by capillary action.

#5. Pickle and wire brush the area for clean up. Check the seam and file off any excess solder if needed.

For general information on brazing and the strength of silver brazing, click here.

For further study, also see what MS Wayne Goddard has to say, more information.

Wednesday, July 18, 2012

How To: Filing Shoulders With Inside Radii For Tang To Ricasso Transitions

This technique helps distribute stress more evenly through the tang to blade transition area during heat treating etc.. This can be easily done with a round file, and a flat file with one blind side with rounded corners. An ordinary flat bastard file can be modified with a bench or belt grinder. The round file is for establishing the inside radius, and the flat file with the rounded blind side for flushing off and squaring up the tang to the ricasso angles without disturbing the inside radius.

Friday, July 13, 2012

Tip: Hand Sanding a Knife Blade.

This technique is helpful with seeing and establishing nice crisp “grind lines” on knife blades with multiple planes. By using opposing angles on the different planes, light reflects off the surfaces differently and there is a more visible apex where the lines or scratches from sanding meet up. In the pictures the lines on flat part of the blade run parallel to the blade and the lines on the bevel run diagonally. Once it gets down to the finest grit or finishing, when very little material is being removed, the lines can all be run parallel for more of a standard looking satin finish or hand rubbed polish if desired.

The angles of the lines can be changed as the grit goes down. This also helps to see the scratches from previous grits as the surface is refined whether with single or multiple planes.

Monday, July 9, 2012

Tip: Draw filing a knife blade.

This is a great technique for keeping the planes on knife blades flush, even and straight while filing. Instead of using a forward or diagonal motion, the file is held perpendicular to the blade “drawn” back and forth in a parallel fashion to the profile of the blade.

Friday, July 6, 2012

Tip: Marking steel with a brass stylus.

This works well on steel with hard fire scale covering the surface, the same way that a pencil point abrades onto a piece of paper. It makes a nice clean durable line.

Thursday, July 5, 2012

How To: Making a Kiridashi.

#1. Start with a suitable piece of steel. I’m using a piece of 1095, approx., 1/8 x 1 x 6 inches long, with a slight taper in width already in it.

#2. Texture one side with a texturing hammer at a forging heat.

#3. Hot chisel a groove in one end at about a 45 degree angle and snap it off in a vice, cold.

After the forging sequence, normalize and stress relieve the 1095.

Recommendation: For 1095, normalizing and stress relieving should be sufficient. Annealing should be done subcritical with a spheroidizing regime if necessary. Avoid slow cooling from above critical.

#4. Stock reduction: File or grind the profile and bevel. Drill a hole at the back end and sand.

Tip: Prior to stock reduction descale the piece with jeweler’s picking compound (sodium bisulfate) or vinegar. Vinegar will work fast if you bring it to a boil, but be sure and do that outside because of the fumes. Also, be sure and do it in a non corrosive container. A ceramic crock pot works well for this. Jeweler’s pickling compound may also be used hot, but it tends to work relatively fast at room temp. Removing the hard iron oxide scale before stock reduction will help save on files and abrasives.

#5. Harden and temper the Kiridashi.

Note: For heat treating specs, click here.

Recommendation: For quenching/hardening sections of 1095, 1/8 inch thick or under, use eco friendly canola oil at 120-130 F degrees. For more information, click here.

Temper at 425 F degrees for one hour and cool to room temperature, 2-3 times.

#6. After heating treating, pickle it again to remove oxidation. Next, rub it with finishing pads first, then extra fine steel wool impregnated with MAAS polish crème to bring up the luster. Use a heat patina (optional) done with a torch and be sure to use a vice as a heat sink so as not to over heat the edge and lose the temper. Lastly, sharpen the edge (no secondary bevel).

Tuesday, July 3, 2012

Tip: Bending jig for straightening knife blades, etc.

This tool comes in handy for straightening blades out of an interrupted quench,… when you don’t have much time and otherwise for bending and straightening hot steel. It’s simply a 3/4 inch round bar of steel, bent into a “U” shape and held in a leg vice.

Monday, July 2, 2012

How To: Forging an “ugly” face on the end of a square bar.

These are fun. I use them on the ends of blacksmith knives a lot, to add detail and give the knives a bit of character.

(Note: All steps are done hot, though not shown in the pix.)

#1. Forge all four corners in on one end, tapering and blending into the length of the bar.

#2. Shoulder the end over the edge of the anvil to form the brow and snout.

#3. Punch the eyes.

#4 and #5. Punch the nostrils with an oval punch and cut a slit for the mouth with a slightly curved chisel.

#6. Make an indentation for the teeth with a flat faced punch.

#7. Punch the spaces between the teeth with a slightly curved chisel and wire bush to clean up.

Here’s an example of one of my blacksmith knives with an “ugly” on the end.