Make a Point Tool

While at Woodworking in America 2015 I attended a class with David Marks showing his woodturnings.  He passes some tools around and one that caught my attention was the tool he referred to as the point tool.  He went on to say how to make it and I left with an idea for a new tool in my turning arsenal.

After making the brass mallet from an old machinist mallet seen here, I had a 6″ length of bar stock in my possession.  What to do with it?  Turn it into a point tool.  But it was plain mild steel.  Tools need to be more durable than mild steel to keep an edge.  I have seen plenty of videos on how to make knives from old saw blades or rail road spikes to know how to harden and temper steel so I decided to give it a shot.

So I began.  The first issue was how to get the three bevel equally around the bar stock.  The solution was within the high school subject of Geometry, triangles specifically.  The equilateral triangle has 3 congruent sides and 3 congruent angles.  There is part of the solution to my problem.  The next was finding the center.  There are different types of center in triangles: Centroid, or the center of balance in a triangle, the outcenter, the center point which a circle can circumscribe a triangle and touch each apex of the triangle, and the incenter, the center point which a circle can inscribed a triangle and be tangent to midpoints of each side.  Since I had to drill a hole for the steel rod to be fixed into the answer was simple: the incenter.  To find the incenter the intersection of the angle bisectors need to be found.  For any other triangle this isn’t as simple.  A compass needs to be used to bisect the angles.  BUT since this is an equilateral triangle, the nature of the triangle states that the angle bisectors will pass through the midpoint of the opposite sides.  Hence, all I needed was a straight edge.

Now with the incenter found I drilled a 7/16″ through hole and glued the rod into it to keep it from slipping or twisting whilst grinding the bevels.

I then started grinding slowly until the bevels were approaching the appropriate length, which was found by multiplying the diameter of the rod, 7/16, by 1.5.  So 7/16″ x 1-1/2 (or 3/2 for ease of multipying) = 21/32″.  I then drew a line on the grinding platform as a reference point for the grinding block (triangle) and finished the bevels.

Now to heat treat the steel.  Using MAP/Pro torch, I heated the 2″ of the end to 1500 degrees (when the steel turns red) and then quenched it in oil.  Water could be used but oil is better for mild steel.  Then the steel is tempered in the oven for 4 hours set to 400 degrees.  No need to dilly dally here, use this time to turn the handle.

I chose a piece of figured Maple with a copper cap as the ferrule.  I like to use caps instead of pipe because the cap covers the end grain in the handle.  I drilled a 7/16″ hole in the blank, in the cap,  and turned the tenon on the end to fit the ferrule.  The shape of the handle is entirely up to the user.  For fine detail tools I like to have a shorter handle.  This may change over time and if it does I will just remove the rod from the handle and make a longer one.  No glue on this means it can be disassembled.  It is still very snug but it can still be disassembled.

With the handle shaped, sanded, and the ferrule on, I applied the finish.  My finish of choice for most tools is a Natural Danish Oil.  It wipes on easy, brings out the figure in the wood grain, and dries quickly.

After the steel has had time to temper and cool to room temperature it could now be driven into the handle.  I put a scrap block of wood down with the point of the tool on the block and tap the handle with a dead blow mallet until it is seated.  Then I regrind the bevels and it is off to the races for this new (reclaimed steel) tool.

If you are interested in making a point tool of your own I would suggest buying a length of high speed steel (HSS) or tool steel bar stock so you can skip the tempering process.  It will also hold an edge much longer.

 

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