
I am at last getting round to completing a lathe restoration which for various good reasons has not been finished. I have odd things (grub screws, pins, lost screws, etc) to do as I rebuild in sequence.
The last item to attend to is the sliding gear arm of the quick change gearbox which should give 4 to 28 threads with lever in, and out position 32 to 224 threads. Indecision, dithering, and doubt creep in causing stagnation of any thought and I would really like any comments and help offered please. I dont envisage ever needing 224 tpi.
It looks dirty from a rust solution I had it soaking in having dried on it so it has has a light brush up to go. I cannot move it apart. Totally locked solid. I tried home made wedges but possibly due to not being accurate enough did not work at all. I may have levered it very lightly apart. My assumption is; it is one shaft (or one with in one) with the direction division being at the a cog wheel with a gap of about 3.5mm. There are I presume two balls on springs which locate and stop the arm on the left in the wanted position. As it is on a sliding 'thingwaybob ' (key way?) it does not turn. I suspect the buried srings will be badly corroded and stuck fast or broken, and so to clean it up by stripping down.
Can anyone give help please with possible advice as how to best to get it off and strip? It is a Fortis late, built in Cornwall late 40's early 50's and was based on the American Clausing lathe. I think I have managed to save it but would like to see it finished, test it and see if I have or not! All help would be most appreciated. I havent wanted to use force in case anything goes wrong!
I could make up a puller of sorts and try that using flat bar and a screw possibly bolting them together (could dig out old welder) for rigidity. I could buy and an willing to buy a prop. made one just to get on to do the same task. The small space for puller teeth of the cast variety limits access is about 3mm. The larger cog, at present removed, is joined to the small cog by the dowel pin.
I may need to put it under tension and wait a day or so for it to crack in the night and so brake the rust bond. I dont see how I can bore or dig out the balls and springs. I am sure I have seen slide levers like this many years ago….somewhere, and must have been fairly common on pre-war machinery.
Every best wish to you all.
M
PS
I learnt many years ago not to go out to the workshop for a second chance late in the evening to resolve something. It invariably meant you were tired and didnt do it quite right and were heavy handed. Best to wait until the morning!