Water Jets?


I've had several local folks tell me that water jet cutting can get me the same result as the laser cutter...is this accurate?


That seems like a reasonable claim. I've used the waterjet at TechShop for other things (like cutting through metal- it can cut through 6" of stainless steel!) but it can do thin- soft stuff as well. Acrylic is a bit brittle so there is some risk of cracking, but I think it would work. Three things to be aware of while doing this though:

1. The width of the jet is different (thicker) then that of a laser, so the cut pattern will not produce parts that are the right size.

2. The waterjet leaves a texture and sometimes a slight taper on the edge of parts, so things like end caps may not work as well.

3. The waterjets are quite expensive to run (the waterjet at TechShop uses more energy then the rest of the shop combined when it's running and also consumes huge amounts of abrasive garnet while running) so unless you're really in a pinch, it's probably much cheaper to find a laser cutter to use.

I've toyed with the idea of cutting an OpenROV out of aluminium sheeting using a waterjet, but since it probably wouldn't be functional and would be over-ballasted, I've never perused it.



At last i can add something useful.

The waterjet will get the same results with the right kind of machine, The jet thickness is easily compensated and if the machine is a flow dynamic then the taper is also automaticaly compensated, The other thing is the machine needs to be able to do a low pressure pierce which reduces the risk of the material cracking.

Waterjet does have one advantage over laser and that is the lack of heat so less chance of stress fractures, this may not be a problem for acylic but many other materials do suffer on lasers.