Tuesday, 11 January 2011

How (not) to Build a Workshop

In 2006 I fulfilled an ambition I'd held since I was twelve..I became the proud owner of a lathe. Now I could progress my rocket project. Or so I thought. The lathe I had bought was a fairly inexpensive Chinese import. It was of a type that boasted a mill/drill head incorporated into the headstock.

 You get what you pay for, and I soon realised the machines' shortcomings. I decided it was a better option to buy a second hand, high quality British lathe than to spend more on modifications to make my Chinese lathe into the machine I needed it to be. 

My requirements for a lathe were:-

Geared headstock
Screwcutting gearbox
Power crossfeed
Coolant system
Camlock chuck mount
Quick change toolpost
Single phase motor

I spent a good deal of time deliberating before I made a purchase. My initial port of call was the Myford range. Reckoned by many to be the ultimate amateurs lathe. I found it to be somewhat over priced for what is essentially an outmoded design.

I decided to go for a Harrison M250. The Harrison company has a pedigree going back to the halcyon days of the Industrial Revolution. It is situated in Heckmondwike, West Yorkshire. The county of my birth and the cradle of British Engineering. So called model engineering lathes often sacrifice some functionality in return for compactness and affordability. Whereas the M250 is a scaled down industrial quality machine, designed for small one off production work. It has many constructional features more usually associated with precision toolroom machines. They were in full production throughout the 1980s and 1990s and were much favoured by schools and colleges. There was also a factory single phase version. You can read more about the machine here:-

I found a genuine factory single phase M250 on a secondhand machine dealers site, here in the UK. My new (to me) machine arrived wrapped in polythene and bolted to a pallet. I had to chop out sections of the pallet with a circular saw, to make room for my engine crane. Once this was in I lifted the lathe off its' pallet and fitted the base with resilient, adjustable machine mounts.

 Once on terra firma I inspected the machine thoroughly. As I'd expected from the photos I had seen prior to purchase, it was in superb condition, basically just needing a good clean. I set to this and also changed the headstock, screwcutting and saddle gearbox oils. The well illustrated manual was excellent, giving recommended lubricants and equivalents. I also fitted a new 50 volt 60 watt bulb to the machine lamp. I got it here:- http://www.lightbulbs-direct.com/ 

Inspection of the headstock gearbox revealed very little wear. The machine seemed hardly to have been used. This was also borne out by the condition of the paint on the pedestal; generally the coolant (especially the soluble variety) tends to lift the paint. The finish was more or less intact. I ran through the manual and adjusted the motor mounts and all the gibs in the ways. I decided not to use soluble coolant - it starts to smell and I have always questioned the wisdom of allowing a water based fluid to sit on precision steel surfaces. It causes corrosion, no matter what the manufacturers may say. I used Castrol Ilocut 486. Shining like a new pin and adjusted to perfection the machine was now ready to be tested.

While all this was going on, I had also invested in a mill/drill and a metal cutting bandsaw. The mill/drill and the saw were both of Far Eastern origin. In contrast to the purchase of my first lathe, I had been able to visit the dealer and inspect the machines thoroughly. I'm pleased to report that they were both well built, sturdy and workmanlike bits of kit. They have given me excellent service so far.

I now had the makings of a decent machining capability. Next I'll relate what happened when I switched the new lathe on for the first time.

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