Inverting a bottle jack. Part 2

Another gallery shows how I modified a bottle jack for use in a workshop press. It worked very well but after a period of non-use the main internal seal leaked and dumped all the oil over the floor one night while I slept. The easy way would have just been to replace the seal but I had an idea that would avoid the mess if the seal ever failed again. Firstly I decided to hone the cylinder to ensure that the new seal had a good start. As one picture shows the initial honing showed a spiral pattern indicative of a cylinder made by wrapping steel sheet in a helix instead of using DOM tubing. No wonder the seal leaked. Did someone mention cheap Chinese tools?
Some measuring showed just how poor the cylinder was, so I decided that it was better to hone the cylinder true even if it meant making it a bit oversize. The seal would have an easier task in a true but oversize cylinder. Then I junked the outer containment cylinder to just leave the inner working cylinder. This was then piped to a reservoir for feed and return flows. I addition I added a drain tube from the lowest point which is not subject to the working pressure. Now if the main seal leaks at all the fluid will simply drain down to the reservoir. This drain also allows air to flow in or out as the piston moves up and down in the cylinder, displacing air in the gap between them.

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