A Water Jet Cutter From A Cheap Pressure Washer

We’ve become used to CNC mills and 3D printers becoming staples of our workshops, and thanks to the wonders of international trade even a modest laser cutter is not beyond the reach of most experimenters. But there is one tool that has so far evaded all but either commercial operations or the extremely well-heeled, the water cutter. These machines use a high-pressure water jet, usually carrying a stream of abrasive particles, to cut through the material placed beneath them. From our perspective they are interesting in that they can cut metal, something not normally possible with the laser cutters within our reach.

A water cutter is something you might think would be impossible for an experimenter to make for themself, but [Applied Science] is on hand to disprove that notion. He’s taken a cheap pressure washer, and modified it to produce a much higher water pressure for a water cutting head.

His very detailed description of the modifications makes for an extremely interesting watch, and we’ve placed the video below the break. The higher pressure is achieved by modifying the washer’s pressure on-off switch with a newly-machined sleeve and a stronger spring. The description of how the washer switch works is interesting in itself. Then we are treated to a complete teardown of a water cutting head, with abrasive feed, tungsten carbide tube, and ruby nozzle. This last component is surprisingly cheap. He then gives us a run-down of its design, particularly with respect to choosing the size of the orifices to match the pump. Finally we take a look at his abrasive feed system, and the plastic funnel he uses to keep water flow back out of his hopper.

For now the cutter is static, but his obvious next step is to bring it to some form of CNC table. If this project brings water cutting one step closer to the masses, we can’t wait!

We’ve featured more than one water jet cutter here in the past, but nothing at this low a budget. A group of students built one for about $5000, while there was a crowdfunding campaign for one at about $3500.

Thanks [varun s] for the tip.

Filed under: tool hacks