Many of the early machines were home-built systems consisting of purchased components such as pumps and nozzles married to other components for control and positioning. But these were prone to a lot of problems that have been addressed in the factory-built systems.
Here are some recommendations:
- Learn what the new machines can do
Visit several manufacturers and trade shows. This will help you understand what you are getting yourself into, and so that you can get some ideas if you still want to continue. You may also find that a manufactured machine will suit your needs very well.
- Join the waterjets discussion group
The Waterjets discussion group is a community of over 2500 waterjet users from around the world. There, you can ask questions and discuss ideas with other people who have done this.
- Use this web site as a resource for finding vendors of spare parts and accessories .
X-Y positioning system
Making the X-Y positioning system to position the cutting head is the easy part. Just be sure it is well-protected from dust, grit, and moisture, and that the operator of the machine is safely protected. Use enclosed bellows and non-rusting components wherever you can. Be wary of simply adapting an old plasma table, because it probably will not have the protection needed.
The controller is the part that controls the movement of the waterjet head. Since waterjets cut mostly by moving across material, controlling the speed of movement is critical to getting efficient cutting.
Making your own controller is not easy. You should definitely read the controller section of this web site for a brief overview of the complexity involved, and options in this regard. Doing it right is a huge effort, but the differences in ease of use, cutting speed, and part quality are dramatic. One manufacturer was able to speed up cutting by well over 200% over traditional non-waterjet specific controllers by optimizing the tool paths based on precision cutting models and such. Precision and edge quality of the cut were also improved dramatically. And all of this was achieved by optimizing the controller software.
That said, if precision and cutting speed and cutting quality are of no concern to you, then there are many controllers out there to choose from. Though if this is the case, you may also want to consider some other technology for your cutting, such as plasma or torch cutting.
Making your own pump is probably the hardest part. There are a lot of trade secrets to making a pump that can last more than just a few seconds without being dangerous. Instead of building your own, you should buy a used pump. There are quite a few used pumps on the market including factory rebuilt ones available from the pump manufacturers, and you may be able to find some on the internet. The waterjets discussion group is a good spot to post a “pump wanted” message.
Don’t expect to be competitive with a lot of the manufactured machines out there. These machines have years of development behind them in terms of software to control and optimize the tool paths, cutting models, and many other features and accessories that make them highly competitive. If you are doing this as a hobby, then have fun and be careful. If you are doing this for a business, know what you are getting yourself into.