I’ve been trying to sort a problem out with the website which means that I can’t upload photos. Hopefully I’ll get it sorted out soon but in the meantime I’ll just have to do without.
I was brought up with Smart and Brown lathes; my dad has had a Model A for around 50 years and a 1024 VSL for around 20 years. It wasn’t therefore a huge decision what I would look for when I started to put my workshop together a few years ago. The lathe I bought (unseen off ebay) was a Model M Mk2 which was a very nice 4″ swing tool-room lathe from the late 1940’s to the end of the 1950’s.
It was in a pretty poor state and I think it was a long time since it was a cossetted tool-room machine. Undoubtedly shifted to some unswept corner of the maintenance shop to turn spacers on. I made several other posts about the assessment and strip-down but the most significant matter was the slide-way wear. There was 0.010″ over the length which is quite a lot!
I had wondered about grinding and looked into the costs, but it didn’t seem to be a perfect solution. True it would be a lot quicker than scraping but I could see the possibility of knock-on problems. I wanted to keep the original position of the head, which provided the correct clearance arrangements with the feed drive gears at the rear. One grinder I spoke to suggested that they had ‘shaved’ gears to get over this problem. It just didn’t seem like the right answer. Whatever I did I was going to have to re-establish the original height of the saddle once the work had been completed to ensure that the half nuts still centered on the lead-screw, the feed shaft within the apron, and the main traverse gears had the correct clearance with the rack.
So, to cut a long story short, I decided to scrape the slide-ways using a hardened rail sitting on part of the original head location face and the end of the tail-stock slide as a guide. With a clock stand moving along that whilst clocking the front way, I was not only able to see the initial wear but it gave me a basis from which I could start the work, so that I could start to scrape the worst of it out and establish a reasonable state of parallelism before moving to the next stage.
Months of intermittent scraping have followed. A bit here, a bit there. A few weeks ago, I had arrived at the point of being within 0.001″ over the slide-way according to the clock and so I went to blueing the rail and using it directly on the slide-way to establish a better flatness.
Anyway, months of intermittent work ahead but the first stage is complete.