A press can be one of the most useful additions to a workshop, once you have one you will wonder how you ever coped beforehand when it came to all manner of pressing in and pushing out tasks. An arbor press with a big lever and ratchet is very quick to use, while a hydraulic press gives much higher pressure but is extremely slow. [The Buildist] missed out on an arbor press, so turned his eye to improving the speed of his hydraulic one. The solution came from an unexpected source, an airless paint sprayer that had come his way because its valves were gummed up with paint.
An airless paint sprayer is simply a high pressure pump that supplies paint to a nozzle, and that pump is easily repurposed to pump oil instead of paint. Testing revealed it could produce a pressure of 3000 PSI, which would be plenty to move the hydraulic jack even if the hand pump would be needed to finish the job when higher force was required.
What follows over two videos is a masterclass in hydraulic jacks, as he strips down the jack from his press, and modifies it not only to take an input from the pump, but also to run inverted by the addition of an oil reservoir pick-up pipe. Along the way we learn a few useful gems such as the fact that a grease gun pipe is the same as a hydraulic pipe, but much cheaper.
The result is a jack that extends quickly, and has the pressure to do most pressing tasks without the hand assistance. He crushes a drinks can for effect, then pinches the end of a piece of pipe, because given a press, why wouldn’t you! Take a look at both videos below the break.
Nice build, and good reuse of an old paint sprayer. But I still don’t understand why he felt he had to invert the bottle jack. Seems to me he could have tapped the reservoir at the bottom, no matter which end of the cylinder was up or down.
Well, i think he wanted to use the business end of the bottle jack instead of its base to push on things. The addition of the tubing that is visible on the video thumbnails on the left side allows the jack to still be operated by hand. Without it, the pump handle wouldn’t work any more.
Since the ram on the jack doesn’t have a great deal of travel, having the ram pointed downward gives the ability to use the built-in jackscrew for quick height adjustments, lessening the need to move the table up and down as often. And it allows for custom pressing pads/heads that can be attached directly to the end of the ram.
Thanks, I rewatched the video and he explains it around the 8:00 minute mark. He wants to use the ram’s head for smaller pressing duties like the head of an arbor press.
Most bottle jacks actually operate up to around 10000 psi. You can get air powered bottle jacks and use those in the presses and get more force.
In the video he says this would theoretically go to ~12,000, he can just get the first 3k from the electric pump and then switch to the hand pump after.
Fast is one thing , but can you stop it quickly when things start to bind or crack?
For doing delicate work I use the hand pump once I get close.
Nice build and I really enjoyed seeing the bottle jack dissected. I had never seen that before so I thought it was really interesting. Now more than ever, I wish I had a more full sized lathe though!
A check valve could have been used instead of the manual valve between the pump and jack? Also a safety valve that would let out the pressure at lets say 2800psi?
Our Dad fancied himself a handy guy, and when we lived on 78th St in the late 60’s into the 70’s we shopped at Beacon with him all the time. He continued to live there into the 21st Century and continued to fiddle with stuff in his house. Any small business is a loss, but this one is personal. Glad you will be able to go to Janovic. All good luck!