Steve Culver Knives

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KMG Grinder Jigs and Attachments

Integral Grinding Attachment

The platen is Ό” x 3” x 12” that has been cut down at the end that fits into the small wheel fork.  The end that fits between the fork is 2 Ό” x 2”.  That area has been milled down on the back side to a thickness of 3/16” to allow it to match the top radius of the ½” wheel.  You will also have to file out the corners of the small wheel fork slightly, so the platen can fit properly.

The angle iron “riser” piece is 2” x 2” angle iron.  My “riser” is welded about 1 3/8” from the end of the platen.  That is the distance (on my machine) that positions the platen to fit under the belt.  You want the belt to lie smoothly on the top of the platen, so position your riser to lift the belt slightly as it runs over the top end of the platen.

The base plate is Ό” x 3” x 5” with two 1” long slots milled into it for the attaching bolts.  I drilled and tapped two Ό” x 20 holes in the top of the small wheel fork to attach the platen.

To attach the platen to the machine; slide it onto the attaching bolts and move it into a position that matches the top of the wheel (I use a straight edge to check) then tighten it down.

Clip Grinding Attachment

The work plate on the clip grinding attachment is 4” X 20” X Ό” steel.  The brackets are made from 3” X 3” X Ό” angle iron.  The arm to attach it to the KMG is 1 ½” X ½” X 10”.

A 3/8” slot is milled in the arm that attaches the fixture to the KMG.  The fixture doesn’t need a long range of motion, so you only need to make two shorter slots centered over the attaching bolt holes. 

The angle iron brackets were clamped together and two holes were drilled of the size required for tapping 3/8 X 16 thread holes.  The two holes in the bracket for the work plate were drilled out to 3/8”, and the holes in the bracket for the attachment arm were tapped with 3/8 X 16 threads.  The attachment arm bracket was clamped in the vice on the milling machine and the work plate bracket was bolted to it through the pivot bolt hole.  The bolt between the two parts was left loose enough so the work plate bracket could move.   A 3/8” end mill was lowered into the other hole in the work plate bracket, the mill turned on and a Crescent wrench was used to crank the bracket into the end mill and cut the curved slot for the adjustment bolt.

Bolt the attachment arm to the KMG.  Assemble the brackets and the work plate and hold them in place with C-clamps.  After squaring everything up, tack weld the parts together.  Take it off of the KMG and weld it together solidly.  DO NOT overdo the welds!!!  This fixture does not take a lot of pressure in use, so it doesn’t need huge welds.  The long piece of steel that the work plate is made from will probably warp when you weld it.  The more you weld, the more it warps and it will have to be straightened.

Once the attachment is welded together, the unit will need to be fitted to your machine by installing it in front of your flat platen and marking it to saw and grind a section out to fit around the flat platen.  Install the attachment to your grinder and make marks on the work plate, about an eighth of an inch outside both edges of your flat platen; laying out vertical lines about 2 1/4" apart.

Draw a horizontal line between the two vertical lines, and about 3/4" below the top of the work plate.  Saw out this rectangle area.

Put the attachment on the grinder and set the angle of the work plate to about 10 degrees.

Loosen the mounting bolts slightly, so you can slide the attachment.  Start the grinder and push the attachment into the running belt to grind the back side of the work plate.  This will relieve the back of the plate so that when you use the attachment, the face of the belt will be close to the front surface of the plate.  Grind into the back of the plate until there is about an 1/16" lip left at the front.

Use a file to clean out the corners of the relieved area.

I have put painter's tape over the work plate on my attachment to protect the blade from scratching.  Other materials could be used; and may work better too.   I've heard that it was possible to have things ceramic coated.  Ceramic coating is very hard and slick.  This may be a good option.

The sharp corners at the back of the riccasso tend to dig into the painters tape on the work plate.  I have found that it helps to also put tape on the back of the blade.

Install the attachment to the grinder and set the angle that you wish to use for grinding the blade clip.  20 degrees is often a good angle to use for bowie knives.

To use the attachment, hold the knife blade down against the surface of the work plate at the riccasso.  Raise the front of the blade up into contact with the grinding belt.

To cut radiused plunge cuts in the clip, I made a secondary platen with the edges rounded to go over the flat platen on the KMG.  (If you like for your clips to have a square shoulder where they end at the spine, you don’t need to use a second platen).  I made the secondary platen out of micarta and used a 3/8” radius round over router to cut the radius on the edges.  It is held in place on the KMG flat platen by two 1/8” pins.  The secondary platen would be better if made from steel.  The micarta wears quickly from the belt going over it.  I usually cut the clip in using only the flat platen on the KMG and then install the secondary platen just to cut in the radiused plunges.  I recommend making the secondary platen out of steel, radius the edges as you wish and then heat-treat it.

This is a digital angle gauge that was made for woodworkers to set the angle of the blade in a table-saw.  It works great to check and set your flat platen 90 degrees square with the work rest and to set the angle on the clip grinding jig.  The bottom of the digital gauge is magnetic, so you can stick it to the steel platen.  It also has a zeroing button, so you can set it on the work rest, zero it, and then attach it to the platen to see what angle the platen is to the work rest.

Install small stops behind the ends of the angle iron brackets that hold the flat platen.  The stop plates have slotted holes so the plates can be adjusted.  This allows you to take the platen off for slack belt grinding and then re-install the platen and it will go back on the machine square with the work rest.

This is a 30" long piece of 3" x 1/4" steel that is bolted to the work rest to provide a longer support for grinding long blades.  The long plate has been drilled and tapped for 1/4" bolts that come up through holes drilled in the work rest.

This is a small platen that is bolted under the grinding belt by a drilled and tapped hole in the platen fork.  The bolt slot in the small platen is slotted for adjustment.  I use this small platen for starting the rolled edges on my blades.

I have drilled and tapped holes in the platen fork to allow me to bolt the work rest onto the fork in a vertical position.  I had to mill about .030" from the work rest arm, just behind the work rest to allow the work rest arm to clear the platen.  This set-up makes it a lot easier to grind things like the edges of handle slabs square.

A piece of angle iron bolted to the top of the round wheel arm makes it possible to use the work rest in the vertical position with that attachment.

A piece of angle iron is used again on the small wheel attachment to mount the work rest vertically.

To facilitate a difficult grinding operation, I removed the small wheel attachment from the tool arm.  I then installed the work rest on top of the tool arm and used pieces of steel to shim the small wheel fork up to the height that I needed for it to be.

Any piece of steel can be clamped to the work rest to provide extra area for positioning parts for grinding.  This is a plate of 3/16" steel that was cut to fit around the side of the flat platen.

 

Shop Jigs and Fixtures

This is the most used fixture in my shop.  It has been used for drilling precise vertical holes, holding parts for milling and a multitude of other uses.  It has threaded holes for attaching clamps to hold parts and also precisely placed holes to pin two folder handles to it for milling.

This jig is made from two pieces of precision ground bar stock.  The two pieces are bolted together and are made to set in the jaws of my milling machine vice.  The tops of the milling machine vice jaws are surface ground flat and square with the top of the milling machine table.  This jig will set on top of the vice jaws and provide a work surface that is square with the milling machine table.

One of my uses for this jig is to drill pin holes through the handle material and tang of a knife.  The knife, with the handle glued on, is clamped to the jig by the riccasso.  A piece of wood is used with a tapered wedge to hold the handle rigid so the pressure from the drill doesn't cause it to flex downward.

This is a handy little jig for a multitude of uses.  It is just a standard Dremel router base that has had a piece of Micarta added to it.  There is a hole in the center of the Micarta for the attachment to fit through.  The height of the attachment can be set by use of the router base's adjustments.

The Dremel can be fitted with a sanding drum for grinding the edges of parts, or with an abrasive disc to cut grooves in the sides of fittings; like a ferrule.

This is a mandrel for shaping a San Francisco style handle frame; like the handle in the third photo.  The center mandrel piece is made of steel.  The outer pieces are made of aluminum.  The strip of frame material is clamped between the mandrel parts and then the edges of the material are hammered over the center mandrel piece.

The second photo in this gallery is a shot of the formed handle frame after being measured for the width of the edges.  The edges of this frame were trimmed to an even width, using the Dremel jig above.

 

    6 inch leg vice on wheels.

 

This is a set of tools that I made for cutting a groove around an oval guard.  They are made of 3/8" micarta, cut to 7 3/4" long and 5/8" wide.  An 1/8" slot is milled all the way through the micarta, stopping a short distance from each end.  Both ends of the micarta piece have an 1/8" hole drilled into the slot.  A 1/8" chain saw file is inserted in one piece of micarta and an 1/8" piece of drill rod is inserted into the other micarta piece.

The tool with the file inserted, is slipped over the edge of the guard and used to cut the groove.  A piece of sandpaper is wrapped around the drill rod in the other tool and used to sand out the file marks.  A bullet shaped Cratex point is held in a pin vice and used to polish the bottom of the groove.

This tool makes it possible to cut a perfectly centered groove around the guard and easily finish the bottom of the groove.

Hydraulic Press

Modifications and fixtures on a Riverside Machine Shop hydraulic press.

Modification to a Riverside Machine Shop hydraulic press. Five nuts are welded to a strip of steel. The strip is welded to the press ram. By moving the bolt between the nuts, the ram can be adjusted so that it does not return all of the way to the top of the stroke.

 

This is a set of pattern dies, set up in a spring loaded fixture. The bottom pattern die is fixed and the top die sets on springs. With this fixture, a damascus knife blade's bevels can be forged in, before pressing the blade with pattern dies. This will give a cleaner damascus pattern from the blade's spine, all the way out to the cutting edge.  Washers are placed around the fixture's guide pin on one side, to angle the top die to match the forged in blade bevels.

Propane Forges

Forge Front View

Forge Left Side Cut-Away

Forge Right Side Cut-Away

Forge Top View

 

 

These are sketches of the cast forge body.  The casting is of Mizzou Plus refractory.  The body is 12 inches tall and 10 inches in diameter on the outside.  The interior is 8 inches in diameter.  The forge body walls are approximately 1 inch thick.  The top and bottom  pieces of the forge are 1 inch thick plates of Mizzou Plus.

The forge body was cast using cardboard forms for concrete piers.  Door openings were cut through both forms.  Pieces of wood were cut from 2x6 boards to block out the door openings.  The wood blocks were inserted through both forms during casting.  This helps to stabilize the forms and shape the door openings.  When cutting the wood blocks, put a slight taper on the edges of the blocks, towards the interior of the forge.  This helps with removal of the blocks from the cured refractory.

The flame opening was formed using a piece of 1 1/2 inch PVC pipe.  The resulting flame opening is 1 7/8 inches in diameter.  The bottom of the flame opening is 1 1/2 inches above the bottom of the forge.  I cast a 4 1/2 inch tall, rectangular block around the flame opening for additional strength.  This may not be necessary.

Both forge door openings are 4 inches wide.  The front door is 5 inches tall.  The back door is 4 inches tall.  The bottom of the doors are 4 1/2 inches above the bottom of the forge.

The cast forge body is overwrapped with 1 inch thick, 8 pound Inswool.

 

Large Vertical Forge

Large Vertical Forge 2

Large Vertical Forge 3

Forge Stand

Forge Work Rest

Forge Work Rest Slider

Forge Work Rest Vice

Forge Doors

Forge Interior Bottom

Forge Interior Top

Forge at Welding Heat

 

This is my large, vertical propane forge.  The cast forge body in the section above is used in this forge.  The cast forge body is wrapped in Inswool and inserted into this steel casing.  The square casing makes it easy to mount doors and other accessories to the forge.

The doors are made of sheet steel, with 1/2 inch Insboard linings.  The doors hang on 3/8 inch rods, allowing them to be positioned on adjustment brackets that are welded to the forge casing.  The adjustment brackets are cut from 1 1/4 inch angle iron.

The adjustable work rest base is made of 2 pieces of 1 inch angle iron, with spacers welded between them.  The sliding work rest can be adjusted for distance to the forge, or removed from the base entirely.  The sliding rest can hold a variety of attachments, at adjustable heights.  I also have a drill press vice on a sliding mount, to use for holding rods for twisting.

The forge stand is made of a "Shop Fox" brand tool table and a "Shop Fox" mobile base.  The table just sets inside the mobile base.  The wood table top is overwrapped with sheet steel.

These are photos of the burner assemblies that I build for use on my forges.  The burner on the white background is made of 2 inch steel pipe, from the blower to the forge.  The nozzle is a pipe cap, with a hole drilled in it.  The gas inlet pipe is 1/4 in steel pipe.  The gas pipe extends about 1 inch into the elbow.  There is no orifice on the gas inlet pipe.  All control of the gas is by the ball valve.  A ball valve works okay for a large burner assembly.  But, a needle valve is easier to control when used on small burners.

Air control is by a sheet steel damper over the intake of the blower.

These burners can be built with either larger, or smaller pipe, depending on the size of the forge they will be used on.  The burner assembly mounted on a small forge, in the above photo, is made of 1 1/4 inch pipe.  This small burner assembly uses the same size blower.

Included is a line sketch of these burner assemblies.

When mounting the burner assembly to the forge, the pipe cap nozzle is not inserted into the body of the forge.  The nozzle just butts up against the side of the forge.  The blast is sufficient to blow the flame into the forge.

The size of the hole drilled in the pipe cap nozzle, is determined by the size of the forge that the burner assembly will be used on.  The hole in the cap in the photo is 1 1/4" in diameter.  This cap is installed on a large burner assembly, that is used on a forge that has about 600 cubic inches of interior space.  Start with a smaller hole size in the cap and try the forge out to see how long it takes to come up to heat.  If it takes too long, increase the diameter of the hole until you have enough blast to bring the forge up to temperature in a reasonable amount of time.

The blower that I use on these burners is a unit that puts out 146 cubic feet of air per minute.  This blower is a Dayton, Model #1TDP7.  I bought this unit from Grainger Industrial Supply.  I added the sheet metal damper to control the air volume through the blower.

 

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