Mason Home-built Lathe
Based on a design fist published in his 1970s book "Building a Small Lathe", this effective little 1.75-inch centre height by 10 inches between centres lathe was built during the Chinese Virus lockdown by John Lukey in Guildford. Based around a bed made from a 2-inch wide, and 1/4-inch-thick steel plate, the rest of the lathe is mostly constructed from standard steel stock With a diameter of 1/2", the spindle has a 'short' No. 0 Morse taper socket and carries a nose thread of 14 x 1 mm. Although plain-turning with no changewheels to turn the leadscrew, Mr Lukey intends to drive this with a 12-volt, variable speed motor to provided a powered sliding feed.
The builder writes: During the lockdown, I was looking for a project and remembered that I had enough steel to build a Mason Lathe. I'd already part-built one of these about 40 years ago for a friend, and he finished it using that lathe. Anyway, the steel had been sitting in my tool shed for 40 years so I raked it out and started the project on the 3rd March 2020.
I did not follow the design exactly, but incorporated some of my own ideas and was also dictated to by what materials I had to hand; hence, this is the "simple" model without the back gears as described by Mr Mason in the 70s. One addition I made was a spindle-mounted, 60-hole indexing wheel - and I also constructed a number of accessories including a faceplate, live centre, adjustable carriage stop, ordinary Morse centres, a fixed steady and a splash-back - and am in the process of making a 12-Volt drilling attachment for indexing. Drive (through PolyV belts). is by a 90W induction motor giving speeds of 395, 775 and 1500 r.p.m.
The builder writes:
I had the 1/4 x 2 inch steel and some of the bits that I had made for the first lathe that I built for a friend 40 years ago. These items included a leadscrew, a Norman type quick-set tool post, the tailstock barrel and feed wheel and the centre part of the cross slide and top slide "V" slides; these were all in a bright mild steel. However, most of the stock that I have is brass, aluminium and dural, so I used dural for the outer bits of the cross-slide and top-slide "Vs." One of more the difficult things I found was lining up the headstock - made from two pieces of 1"x1" steel bar - with the bed. The bed, constructed from 1" x 2" bright mild steel, is spaced apart by the headstock bars and two further 1-inch diameter spacers bolted through with 6 mm bolts and an end plate of 1/4" aluminium; the top of the bed is then secured by means of 4BA c/s screws. I used a 1/2" silver-steel bar to line things up as best I could, but this was time consuming as the reading were not always consistent. It all seemed to work out in the end and the centres in the headstock and tailstock now meet point-to-point!
Made from two blocks of aluminium riding on a 1"x 2" steel plate fitted to the bed ways, the tailstock - with a 'short' No. 0 Morse taper barrel - has its locking lever fitted with a brass thread to bear on the bed so as not to mark it - and this proved to be a successful design.
The motor I'd had for many years - and I know little about it, or where I acquired it (I have always collected thing like this and found, eventually, that all finally have a use - you just have to remember where you put the darned things….). The motor did have a faded label that read "Universal Motor. Co. Owosso, Michigan. No oiling required, thermal protection. O.83A 2500 RPM". The motor measured 90W on no-load and seemed adequate to drive the lathe. As I wanted to get the motor as close as possible, tucked in behind the countershaft brackets, the drive arrangement was designed to take up as little space as possible - and this part of the build worked out well. I used 3/8" silver steel for the shaft running in Oilite bushes, although it proved difficult to get the bushes to line up but, after a few hours of head scratching and fettling, it came right.
Having reached the stage of trying out the motor before making up its mounting bracket, it seemed to run nice and smoothly. Every few days, as I worked on other aspects of the lathe, I would switch it on to make sure all was well but, as I was about to fit it to the lathe, it started to clatter. This became progressively worse over time, so I had to strip it down - and I don't think it was designed to come apart easily! The problem turned out to be the pressed metal "top hat" housing that held the front ball race being loose. The whole thing was flopping about, so I ordered another ball race, fixed the housing - and all was well.
Following the old-fashioned factory way of building a lathe - assemble and checked everything first - the whole thing was taken apart and painted. I used a grey etching primer on the non ferrous parts and sprayed the lathe with several coats of thinned light blue Hammerite Hammer finish. I used a cheap Badger airbrush with a 2oz pot at 35 p.s.i.