Vernon #0 Horizontal Mill

This page describes a Vernon #0 horizontal milling machine that I have renovated and improved. The machine is essentially the same design as the later-produced Sheldon #0 mill. I believe that Sheldon purchased Vernon's mill design, along with the that of a 12" shaper, around 1939. Sheldon did make some improvements to the design, particularly to the variable speed adjustment mechanism.

Here are a couple of pictures of it showing its initial condition which were taken by the party from whom I purchased it.

I believe that my machine was originally used in a school shop; one of the nameplates on it referred to a school district. It seems to have suffered the abuse that a machine in that environment would be expected to see. In particular, the taper on its B&S #9 arbor was significantly marred with evidence of aggressive use of vise grips, probably in an effort to loosen the left-hand thread arbor nut. This fact led me to undertake the effort to refit the machine with an R-8 spindle. Since I also have a vertical mill with an R-8 spindle, this is an economical choice since I can share tooling between the machines.

Instead of modifying the existing spindle, I chose to fabricate a new spindle from scratch. For this purpose, I selected some 1.500" 12L14 stock of suitable length. The spindle's largest diameter, where the arbor enters the spindle, is actually 1.750" for a length of an inch and a half or so. Instead of starting with a larger piece and turning most of it down to the smaller diameter, I chose to add the larger piece on using a press fit, welding it and then turning down the weld bead. Because my lathe's spindle, on which the arbor was fabricated, only has a 1.500" through hole fabricating the spindle in two pieces made the process simpler. This was particularly so for drilling the through hole which had to be done from both ends since I don't have a bit that could drill the entire 15" length in one pass. A picture of the original B&S #9 spindle may be seen here along with the bit used to drill the through hole.

The Vernon's spindle rides in a pair of Timken tapered roller bearings so I decided to machine both bearing seats on the spindle in a single setup in order to get the best concentricity. I decided to do the final machining on the R-8 taper bore with the spindle installed; the theory being that machining "in situ" would provide the greatest accuracy.

To facilitate the finish machining, I acquired the compound from a 14" South Bend lathe and fabricated a plate for mounting the compound on the mill's table. I then used the Dorian CXA toolpost from my lathe to hold the various tools required for the finish machining. Pictures of the setups for the final bore operations appear below.

This picture shows the lathe compound mounted on the mill table and the Dorian toolpost holding a 1/2" boring bar preparing for the finishing of the inner bore. Because the innermost part of the bore is over 4" deep, very light cuts were taken with frequent measurements and trial fittings.
After the picture above was taken, I set up two dial indicators to help me monitor the cutter position; one mounted on the table and indicating on the main casting (near the over arm support bore) to tell me the cutter depth and one mounted on the front of the table and bearing on the knee to tell me the X position.
Here you can see the setup for cutting the initial taper. For this operation, the compound was set to approximately 8 degrees off of the Y axis using a protractor. This taper was intentionally cut shallow so that an R-8 collet could then be mounted and indicated on in order to dial in the exact taper.
In this picture, the collet is installed and the compound is being set to achieve the correct taper. Note the black "Magic Marker" mark on the spindle. A diametrical line was drawn across the end of the spindle using a center square to assist in setting tool height. By comparing the tool height to the mark on both sides of the spindle the cutting tool could be set to the spindle's center height reasonably well.
After the correct compound angle was set, the full depth of the taper was cut with a small allowance for final grinding, the setup for which is shown here. The stone in the die grinder is a crankshaft grinding stone and is very hard. It only took a few passes to produce a very nice ground surface.
Here is a shot of the spindle after the grinding operation. The runout on the taper after grinding was a tenth or two using a 15-0-15 indicator.
This picture shows the R-8 arbor installed in the spindle. Because this arbor is slightly longer than the original, I replaced the overarm support shaft with a longer piece of 2" 1045 Ground & Polished stock. Also, the outboard arbor support bearing needed to be replaced since the new arbor has an 11/16" pilot while the old arbor had a 1-1/2" running bearing.
The mill has a continuously variable drive system that employs a variable pitch idler pulley like that used in the Logan 8" shaper. The original speed adjustment on the Vernon was a notched rod with a catch (shown at left below). I decided to replace this mechanism with a crank like that used on the later Sheldon version of the mill. This was achieved internally using a U-joint and some 1/2" round stock. I changed the threading in the internal lever to right hand to allow clockwise motion to increase speed. The rightmost picture below shows the speed adjusting handwheel and also the zerk which supplies grease (through a hose) to the variable pitch pulley shaft. The later Sheldon models had a similar setup for greasing the pulley.

To mount the zerk, I used a 3/8-24 bolt drilled through and tapped 1/4-28 for the zerk. The bolt is fixed to the casting using an adapter nut made from a short piece of 1" round stock that is drilled through, tapped for the bolt on one end and tapped 1/8-NPT on the other for the grease hose. Flats were milled on the adapter nut to facilitate holding it while tightening.

Finally, there are some shots below of the finished renovation from various angles. The mill was missing the lower access panel on the left side. I fabricated a replacement for it using sheet steel. I also extended the X-axis leadscrew out the right side of the table with a 1/2" square drive on it. This allows me to use my right hand to feed the table. I also cut square drives on the Y and Z-axis leadscrews to allow the same crank to be used in those positions as well instead of the smaller handwheels.

Scans of two different editions of the manual for the Sheldon version of this mill may be found here.