How my home made lathe works

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For forty-five years I worked as an engineer starting at fourteen years old in 1939 as an apprentice mechanical engineer. In those days tools were basic and sparse, so we had to improvise and make our own. No such things as spare parts then, if anything broke it was repaired or remade.

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This is a copy of my ‘lines' as they were called at that time. No fancy typewriters or word processors then. Note the handwriting, most people could write like this in those days, writing being a main subject in education.

When I retired I continued to make things as a hobby, mainly wooden toys, ornaments etc. One item which people kept asking me to make for them was a wooden butterfly Making these butterflies involved quite a lot of hand carving and filing to shape the round bodies, and after I had made quite a few my hands were beginning to show the strain, so mechanical help was needed. Using bits and pieces from the junk box the above lathe eventually evolved.

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These are samples of the butterflies, that required the shaped bodies, and for which the lathe was initially made.

In my shed an old 12"-inch cylinder electric lawnmower looked like it had possibilities. If I could remove the blades and spin my wood in their place filing and polishing would be simple, saving my poor hands.

Making a start I completely dismantled the mower putting aside the handle, rollers and parts I thought would not be needed. The blades were all hacksawn off the main spindle and the welds cleaned up, the two ballraces were cleaned, greased and laid aside for fitting later.

At this point it struck me that to do the job I wanted, a bit more thought was required, and the idea of a lathe was born. Never having paid any attention to wood turning lathes or ever used one, all my plans and ideas were based on the metal turning machines that I used in my apprenticeship days. As you can see from the picture it looks more like one, with the parallel shears or ways running out in front of the headstock.

When the main spindle was in the mower it was only long enough to reach the front ballrace, and finished flush with the outside of the front cheekplate. This spindle had to be drilled and tapped to take a threaded extension the same diameter as the spindle This would hold the chuck, or rather, the driving and holding appliance, still to be designed.

At each step snags and problems appeared. In this instance I felt this extension should be supported. From the junk box a pipe flange with a short spigot was bushed with a brass pipe fitting, bored to suit, then bolted tight against the front cheekplate. Another modification, which had to be tackled was resiting the mower motor to the outside of the casing so that it was driving anticlockwise, the correct direction for turning.

Below is a sketch of the assembly so far, showing the spindle and its fittings.

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In the above sketch the faceplate is shown fitted, but the temporary rod is needed in place to facilitate the building of the bed and shear [way] timbers. A height gauge is used to set them level, with a ruler and setsquare to align them.

The bed sections are 2" x1 ¾" and the shears are 3 ½ x 7/8 oak. The length to suit the requirements e.g. 2ft protruding. Mine were 2 ft because that was the length of the drawer fronts saved when granny's sideboard was scrapped. The wood was hard and smooth ideal for the shears [ways]. You will notice I have inserted the bracketed word ways after the word shears, It was pointed out to me that shears was a local term for the saddle slides and I had to read up the word ways.

I had a bag of 12mm x 115- mm-long bolts, with nuts and washers, left over from my working days. These were used throughout the assembly and made a really strong firm framework.

In the sketch on the next page you will see an additional feature, a heavy-duty electric drill was set up on an adjustable bracket behind the lathe with their centres level. This was for an extra power drive, a bit like the back gear on a metal turning lathe. Although the lathe was ideal for light work ie.butterfly bodies and small items, it struggled to turn large diameters and rough wood. When extra drive is required for this, a switch diverts the current from the lathe motor to the drill, which has a simple clutch arrangement. This consists of a bicycle wheel spindle held in the chuck, a 3" dia. Pulley 3"long with bushes slides on this .To drive, a wing nut pushes the pulley along against the chuck ,a recess in the end allows the teeth for the chuck key to grip and turn the pulley. When the wing nut is slackened the pulley freewheels.

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Below a sketch of the clutch assembly showing the wingnut and the sliding pulley

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A view of the pulley and the wingnut which gives a stronger drive when required

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The tailstock is simply a 6" x 6" x 6" long angle bracket made from the same wood as the ways i.e. drawer fronts. A half- inch drill chuck is clamped in the middle at the exact height of the headstock centre. The bracket is located and clamped in the 3" gap between the shear ways. The hole for the drill chick was actually drilled in situ using a drill held in the headstock, thus ensuring its position was exact. A short piece of half-inch diameter steel sharpened to a point is the running centre held in this chuck.



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The toolrest is again another simple arrangement. A piece of 1"x 1" angle 6" long is fixed to a bolt, with a plate to clamp it to the ways. All these fixtures are very Heath-Robinson and someone with better workshop facilities could easily improve on them.


As I did not have any 3 or 4 jawed chucks the face plate had to be the main holder. A piece of seven eighths thick wood was bolted to the faceplate and turned to 5"diameter then faced up.

This operation corrected any wobbles in the faceplate. Another search in the junk box unearthed a three-phase wall socket the type with a 2 1/2" screwed outer wall and a lid, which screwed on. This outer wall was bolted to the now wooden faceplate,and made dead true. The lid and another three which I found,were the basis of all the holders I use.

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As this lathe was built in stages the wiring is a bit complicated, but it could be simplified. However I will describe it as it is now. The connection to the supply is an ordinary 13 amp plug to an off- on switch on the front of the machine, then to a foot switch, which was added to leave the hands free to use the tools. From the foot switch it ran to a selector switch, which was "Down" for the mower motor via a thyristor based circuit speed controller, and, " Up" for the heavy-duty motor or the back gear, not forgetting to tighten the wing nut to engage the clutch. This arrangement works very well. The heavy- duty drill with the 3" pulley driving the 4" one on the main spindle gives an ideal speed and torque for turning rough work, i.e. tree branches, square timber and large diameters.

The mower motor is very fast, great for polishing, but needs the speed controller to slow it down for intricate turning.

My lathe J was made in the first instance to do the one job,ie turn butterfly bodies. It did this successfully, for interest I tried to make more elaborate articles. To do this, new tools and workpiece holders had to be made, I now have a good selection of both and can make any bits and pieces required for my other projects. Or I can turn a little cup or an ornament to give as a present.



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Some Turnings Main driving fitting exploded


© John K Wilson