Choose Waterjet Cutting

Are you wondering if you should choose waterjet cutting for your next project?  Hopefully this will help you decide.  Waterjet cutting is the ultimate tool for cutting thick materials of most types.  It is extremely good at cutting thick aluminum as the material is relatively easy to cut, so is a perfect fit for the waterjet.  We have cut aluminum up to 12″ thick with our waterjets.  Steel cuts considerably slower than aluminum does, (roughly about 40% as fast) but it will cut steel 6″ thick or more and even the most powerful lasers will only cut about 1″ thick maximum.  So in thicker materials a laser is not even an option.  Plasma or oxy-acetylene torches will cut thicker steel than a laser but the tolerance and cut will not be nearly as good as the waterjet cut part.  Also those processes will leave a heat affected zone (HAZ) which makes any further machining more difficult as it will dramatically shorten the life of cutting tools.

Thinner materials can be stacked up several layers deep, thus offsetting the benefits of the much faster cutting speed of the laser.
There is definitely a limit as to how thick you can stack material and still gain in cutting speed/cost per part.  We will go into that whole calculation in a later post but in rough numbers any stack more than 1/4″ thick will start to become less efficient than stacks somewhat less than that.  The laser and other hot processes will not allow you to cut thicker than one layer deep as trying to do so would only weld the layers together while the material is molten when cutting.  For material that can be stacked you should likely choose waterjet cutting.

Waterjet can cut virtually any type of material as the process doesn’t depend on having to melt the material in order to cut it, so it does not matter how high or low the melting temperature is.  It also doesn’t depend on conductivity to cut as EDM does.  Waterjets will cut very high temperature alloys, as well as paper or wood.  Paper will ignite with a laser beam and while wood will cut, it chars the edges which are not acceptable for many projects.  High temp alloys take a lot of energy to heat up enough to melt for cutting, thus may not work well even if they are thin.

Waterjet is almost always faster/cheaper/easier to run prototype parts on, as it is far easier to program and setup than any mill, and most lasers.  Also if you want to test a part before a production run it is very easy to modify a program and re-cut the part for another test.  So, for prototyping you probably should choose waterjet cutting.

Waterjet can cut parts holding much tighter tolerances than a plasma or torch cutter so even though they are much cheaper to cut parts with they may still not be suitable.

Waterjet is the best process for cutting most any rubber project as conventional mechanical cutting processes do not lend themselves to cutting rubbers.  Laser will burn rubber and a mechanical cutter will likely grab the material and at the very least give a very rough cut if not pull it into the cutter making a huge mess of things.  So, for rubber cutting choose waterjet cutting.

It is a great process that can work well for you if you like artistic, home decor or DIY projects of many types.  It is a great tool for helping to build your own custom security door.  I even have a fire pit in my yard that was made on the waterjet and I promise you that there is not another one like it in the world.

What waterjet cutting may not be best at!

Waterjet is not the fit all process for every person and every project.  For example if you are wanting to cut one part each of say 50 different designs all from the same thin sheet  of metal it might be cheaper to use a laser, as they will cut several times faster than a waterjet will cut.  However you might have a difficult time finding someone with a laser to do the job for you as it would take much longer to program the sheet of parts than it would to cut them.  Many shops are unwilling to work with customers on small one time jobs especially with lasers.  They are very expensive machines and don’t lend themselves well to cutting small one time jobs.  The motion systems on lasers are designed to run at a much higher speed than most waterjet cutting systems, and once a Laser gets the material temperature up to the melting point they will cut at a very high speed.

If you are wanting to put a lot of small holes through thick material waterjet may not be the best choice, as often times a mill/drill will make a hole through the same material much faster/cheaper than a waterjet.  If there is only a few holes and the setup on a conventional drilling machine would take longer than the savings in machine time that would be realized then the waterjet might still be the best choice.  But if the part has to be setup on a mill for further machining or if you have a large quantity of the same part to run it may well be more economical to drill the holes by mechanical means.

If you are wanting to cut a few parts, and can’t justify the minimum lot charge we have ($100), then you may want to consider using a plasma cutter or some other hot or mechanical cutting means, as they are usually less expensive but the tolerances and edge finish are not as good as a waterjet will give and unless you really are bored and just don’t have anything better to do with your time you might find that all of the extra time you take to complete a job is more expensive than just having it waterjet cut.

If you absolutely can not get any moisture on the material that you are cutting, then waterjet is probably not for your job as, due to the fact that water is the cutting media or at least the carrier for the cutting media and parts are normally cut very close to or even under the water the parts will be next to impossible to keep totally dry.

Hopefully you will gain some useful insights into whether you should choose waterjet cutting for your next job.

If you do choose waterjet cutting, then we look forward to working with you here at Accurate Waterjet in Phoenix, Arizona.  Give us a call or email us to discuss your next project.