|Removing the Gear|
|The finished product|
In connection with the acquisition of our 36" Swing American Tool Works lathe, I acquired a collection of chucks for it, as the ancient 24" Cushman which is likely as old as the lathe and in much worse condition. The spindle on the ATW is a 4.25" diameter 4 TPI. The threads are not quite an American standard thread in that they are a little shallow with the minor bore just a few thousands over 4". I went to some auctions and scrounged around on Ebay and came up with 4 chucks for the ATW. The included a 20" 3 jaw Cushman with a flat back, a 20" no name cast iron chuck that was an OEM for an Italian lathe with a D1-ll Mount, an 12" 3 jaw cushman with a flat back and a Kitagawa 12" 4 jaw. My mission was to adapt all those to work on the ATW lathe.
Our first order of business was to get some hub blanks which were simply 7 inch rod cut in 5 inch lengths. We bought those.
Once I got the blanks however, it occurred to me that I should make a sample of the spindle so I could check the thread making to save quite so many 'tries' to get it right. I was actually going to cut the threads on the London Machine Tool Lathe because I don't have the ATW in service yet. While a lathe is the only machine tool around that will make itself and repair parts for itself, it was convenient to have another lathe for some of the work. The chuck mounting work will have to be finished with the ATW under power, but the preliminary work can all be done on another lathe. You will see many of the photos of the hub making on the London Machine tool page, but the sequence of photos here show the making of a 'standard' for the ATW spindle.
We didn't buy any iron for this. Consequently, this meant digging around in the weeds and looking for some suitable iron. Fortunately some was found which between us and the guy we got it from has probably been stored for 50 years or more just for this occasion. Once piece had a gear on it which had to be removed.
I'm not too sure what the gear is for but the shaft was 5 inches --just what I needed.
So after whacking off the gear, the shaft went to the hacksaw. the really nice thing about 'old iron' is that it is usually virgin iron and doesn't have any 'hard spots in it' which the recycled material you buy today often has.
I then turned it a piece into a 'standard' with a major diameter of 4.25 inches and a minor diameter of 4" and I stayed with it until it would screw into my existing chucks and face places for the American Lathe.
With this 'warm up' I was ready to thread the first of several hubs I am making to mount chucks on.