BUILDING THE WORDEN GRINDER

By Vince Cutajar

I had been thinking of making this tool for a while as my results in free hand grinding of lathe tools is, to say the least, atrocious. I ordered the kit from Hemingways. It arrived in less than a week.

There were two carton boxes, one containing the electric motor and the other one the rest of the electrical hardware and two bags of metric nuts and bolts.  All the bar stock and the steel prefabricated frames were neatly bubble wrapped.  There was also some paperwork included which consisted of

  1. 10 A3 sheets of technical drawings

  2. A set of construction notes

  3. A set of notes of how to use the finished tool.

I read somewhere that this kit can be done in three weekends.  Something tells me this is not going to happen especially if I do things the hard way. So, work started on the kit. It is recommended to debur all the pre-fabricated steel plates. Yes, they need it but I did not want to do them all at the same time. It was decided to only debur the part that I would be working on.  Started on the base as recommended.  Deburred that to remove all the rough and sharp surfaces.  The base has three 8mm captive nuts in it. Tried to screw a bolt in them but no luck. So, all captive nuts were refreshed with an 8mm tap.  Much better now.  I guess the start threads were deformed a little when the nuts were pressed in.
Next operation was to fit the two stiffener bars between the top and bottom of the base.  The bars provided were nearly exactly to size. Less than a mm longer than required.  I could have easily left them like that but being me I wanted them exactly to size.  So I lightly milled one side of the bar.  This also removed the saw marks.
A trial fit was attempted but the stiffener bar would not slide easily between the top and bottom of the base.  Two temporary jacks were devised to push the top and bottom apart so that the bar would easily slide in.
Next to mark, drill and tap the bars.  Here I did not follow the instructions as I thought that I would not be able to mark the holes properly and also I could not be certain that when I drill the bars that the 5mm drill will not wander.  So instead, I measured the locations of the pressed holes in the base from the front.  The measurements seemed to be in mm.  Just to confirm that my measurements were correct I asked Kirk if he had a drawing of the base with the locations of the pressed holes which he immediately obliged by sending me a drawing.  As I thought, the dimensions of the drawing were in mm and I had measured correctly.  The holes were marked on the bar and proceeded to start drilling.  I only drilled half way through.
Bar was flipped around and was drilled from the other side.  Next operation was to tap 6mm each hole, first from one side and then from the other.  Trial fit and all the holes lined up and the stiffener bar bolted up.
Finished the other stiffener bar and fitted in place.
Marked the excess on the unmilled side and milled it to the line. Also there is a nice space between the stiffeners to put in a drawer. Fitted three feet to the bottom of the base. These are just door stops that I bought locally. They are not part of the kit but it is recommended that they are fitted.
If I had to follow the sequence of the construction notes, I should have started on the working table.  However, the 4mm number stamps (I only had 2mm) were on order and I needed to study the sliding mechanism beneath the table a bit more. So I skipped that and did something else.

I did the two side plates clamp screws.  Straightforward lathe turning with no special accuracy required.  The only bit I made sure they are both the same is the 10mm collar which fits in the side plates 10mm slot.  I used a fine diamond knurl on the knob.  Knurling is a bit iffy when I do it so I did a test on a piece of scrap before. I did not think that buying a larger tool was cost effective, so I tried opening the scissors as much as possible and then pushing the knurl into the material.  It gave a decent knurl.

Happy to say that both turned out fine.
With these clamp screws finished, I turned my attention to fitting the side plates.  Cleaned up all the rough edges and took a while in cleaning up the slot to make it fit the 10mm collar of the clamp screw so that the sideplate can slide freely when the screw is loosened.  Used a small Dremel grinding stone and then finished up with some draw filing.
Both side plates fitted with the clamp screws.  Measured the distances between the side plates at various positions and the largest discrepancy was found to be 0.3mm.  Not bad.  They seem to be parallel to each other.


Part one here  Part two  Part three  Part four  Part five  Part six  Part seven  Part eight  Nine  10  11