Hydro: The Low Cost Waterjet Cutter

Waterjet cutters are generally huge machines, with equally large price tags. But what if there was a hobbyist level waterjet cutter that was actually affordable? Well, for their Senior Design Project at the University of Pennsylvania, [Adam Libert] and his team made one that could retail for less than $5000.

[Adam] was the lead mechanical designer on this amazing project, and he designed the fully waterproof XY gantry, capable of withstanding the water and abrasive from the cutter. The entire machine is only 2′ x 2′ by about 5′ tall, making it extremely portable and easy to move through doorways — and it runs off of plain old 120VAC and shop air. It is capable of cutting through up to 1/4″ aluminum and 1/8″ steel with a working area of 12″ x 14″ at a tolerance of 0.005″.

Not surprising, the project won the Mechanical Engineering Senior Design competition in 2012 with accolades for outstanding creativity. We weren’t able to find any information on the future plans for this project, but we hope they make it open-source, or even run a crowd-funding campaign for it.

The goal was to create the first ever low-cost, small scale, and easy to use waterjet cutter, and judging by the video, it looks like they did it — stick around after the break to see for yourself.   

103 thoughts on “Hydro: The Low Cost Waterjet Cutter

        1. Holy cow. For a student in college, this is a great accomplishment. Maybe they used some OTS parts, but putting all of this together and making the nozzle work at 10k psi (claimed) is quite a big deal.
          Don’t get caught up in the world of negativity. Efforts like this should be praised. Adam and the team will likely get some great job offers.

          Well done.

          1. Don’t get me wrong, it’s pretty a pretty sweet build. Just curious as to the specifics and want to understand how their design stacks up against “baseline”.

    1. The video threw a few numbers around and claimed their pump/piston thing was something in the region of 10kpsi. I’ve not yet seen any detail about it beyond what was said by someone off-camera when discussing the mechanical advantage of their dual-piston arrangement when working from a 100psi air-line (there weren’t even any close-up shots of it).

  1. I hope they release the design as open-source. It is a wonderful job, but right now it is a black box rather than “available to hobbyists and small businesses on a budget”.

        1. Good luck beating the copycats.

          The reason why open source can’t make bank is because you have to spend a ton of your money in developing the thing, while the others don’t, so you’re at a disadvantage from the starting line even if you did get to market first, since you have to amortize the investment and they don’t. Therefore you can’t afford to sell as cheap as the others and will subsequently lose sales.

          That’s why you always patent, or keep some secret sauce that the others can’t get at.

          1. Or, you simply keep the design to yourself until you have earned back the R&D.
            Due to comments about the off the shelf parts, this is not likely patentable.
            The design however, does have copyright protection.

            I get why people like open source and free, but I don’t get why so many demand that a person not make a living off of their talents.

            Everybody has to eat, pay rent, buy clothes and do all of those other things that no one wants to just hand out, but they sure have a problem with people earning a living off of what they can do.

            So many Christians so completely UN-Christian.
            So many Americans so completely UN-American.

      1. Not really, it is low pressure and there are several companies that make small footprint machines.

        The pump is a pretty generic air/hydraulic intensifier and the stage is controlled with Mach3. No big deal, really.

  2. I do not want to sound negative about this project, but this is nothing special:
    Nearly everything is see in this project are standard components.
    The gentry, the pump, the cutting head, the valve, etc. These are all standard parts, none of them seem to be made especially for this.
    They bought ready-to-use parts at ‘insert WaterJet-supply vendor’ and put it together. Just like you build IKEA stuff.

    1. So?

      Do you expect him to make his own gantry, linear bearings, intensifier pump, cutting head, etc? He’s using Mach3 to control it – do you want him to write his own CNC control software? If your complaint is against using “standard parts”, then that could be carried _ad infinitum_.

      Having looking at waterjets several years ago and wondering whether it would be possible to do a small-scale unit, I can tell you that waterjet heads are not something you even want to consider building. For example, there’s several tungsten carbide parts (nozzle and feed tube) to resist the abrasive. If there’s a standard part available, then by gum, use it. I think you could get a complete cutting head for around $1500 at the time.

      The point is he has a _complete_ machine! Shaddup and take my money ;-)

    2. Which is why it would be awesome if they decide to release it as open source… Pre-made components or not, it’s still an impressive build!

      Most engineering these days isn’t about re-inventing the wheel, it’s about re-imagining it.

      1. hey, thanks for the good press! totally unexpected. how did you come across our project?

        “Most engineering these days isn’t about re-inventing the wheel, it’s about re-imagining it.” – well said.

        in fact, i was hoping not to have to even design my own XY gantry. however, I looked into all the available XY gantries on the market from CNC routers etc., and it became pretty clear that adapting and water/abrasive proofing any of them would have been a nightmare. so, we decided to build our own. which i’m glad we did, because it was a sweet opportunity for a fun design project! in retrospect, there are definitely some changes i want to make to the gantry, but for the most part i’m pretty happy with the way my gantry design turned out.

        we also looked into making our own pump because we had a hard time finding any that we were happy with, but designing a 10,000+ psi pump definitely wasn’t in the scope of the project. we were lucky to find the pump that we did, though i’m still looking for one that runs off of commonly available electrical mains power instead of shop air.

        and thanks everyone for the positive comments!

        1. How many CFM does the “intensifier” use? Some of these use 130+ CFM of air. That’s a solid 30 HP compressor. Most intensifers that output 60,000+ use 25 – 100 HP motors. Using this to generate 10,000 PSI gives you 1/10th the speed at the same cost as a more traditional intensifier, because generating and using that much shop air is extraordinarily inefficient. The motion system is pretty sweet though. I wonder if you could put a hole in the catch tank?

          1. Seems to me that using hydraulic pumps to run the accumualtor intensifier would make much more sense in a closed system whereby eliminating the need for air besides you could essentially operate at much higher pressures on a small intensifier. Simply a servo powered reciprocating pump connected to a hydraulic intensifier seems the way to go. Given a 4000psi car wash pump and nozzle can cut 1/8 steel efficiently you would be able to cut thicker materials at a faster feed rate. A basic arduino would be fine for operation, water proof step/dir servos and a 40mm gantry would make for a nice 2×4 table. Add 18” acrylic panels around the sides for splash guards along with 80 grit gravity fed sand using a one way check valve to prevent backup would be the route I’d consider in a diy prototype machine. All which can be made on a mill and lathe along with some purchased components for around 2k if you can handle a number of self made parts and not depend on off the shelf components. I may have to see about this if love to make an open source project and sell the parts as a kit with instructions for one to diy build.

      2. if you ask me, i think the fact that its all shelf parts makes it a better design. i believe it takes more creativity to make a machine like this without having to machine special parts

      1. Yes, respect! It takes literally nothing to make rude comments on the internet. No prototypes, no failed designs, no intellect. If you actually built stuff you would know it takes hundreds or thousands of hours of design and prototype time, even if you buy the parts off the shelf. Then after all that, some of you want them to give all that work away for free? The internet gives voice to experts who don’t actually know anything.

    3. Your inability to see something special is not this projects fault, it’s your lack of imagination and insight. Having the vision to put stuff together in such a way that it becomes something functional in a way that has never been executed like that before is as special as you can probably hope for doing once in a lifetime.

    4. I think you are being negative, just because most of the parts are off the shelf doesn’t mean choosing parts and putting them together is easy.

      It’s certainly not “Ikea easy” where everything is in a box and they provide instructions.

    5. hey, i custom designed that gantry and fabricated it with my team. maybe you thought it was an pre-made part because it looks so professionally made? :D

      and i’m not sure why you’d be against an IKEA-style waterjet cutter. imagine being able to buy a bunch of cheap modular off-the-shelf components and DIY assemble them into a waterjet or cnc router or 3d printer or laser cutter, all with just slight reconfigurations… sounds awesome to me!

      1. Yes, for example, the Blacktooth laser cutter is nearly IKEA-like. It even uses MDF, nut inserts and cross dowels. IMO, assemble-it-yourself is a tangible and significant step between between design-it-yourself and store bought. It means the design is workable, that a BOM of available parts has been established, software is available/compatible and that it’s been dummy-tested to some extent.

        Another thing people overlook about invention: In the old days of the U.S., it took months and years for inventions to propagate. There wasn’t such a large economy and there was less capital. Also, there was less specialization and fewer different kinds of jobs, requiring fewer varieties of tools. That meant you only ever saw relatively few new inventions each year.

        Nowadays, we see many more remixes, transectorial innovations, and intermediate steps and inventions which differ depending on how they’re used. As if that wasn’t enough, we have pervasive media informing us every time any invention improves by 5-10%! We’re looking harder! So, the traditional definitions of “invention” and “innovation” are outdated. Instead, of these words, try considering whether something amounts to a *fresh formulation* instead and your judgment will be more useful, I guarantee.

      2. Yes, i have seen a comercial gantry like this, so i assumed it to be premade. My fault, and well done on your part. You should show how it’s made.
        No, i am not against IKEA-style. If it works, it works. And i DON’T want to see you try building the high pressure parts. I’ve seen a 26to tool been ripped apart by 80000(!) psi high pressure, parts of it digging deep into the concrete floor, flying through the walls and a mans hand. Talk about bad design….
        Like i said before, i do not want to be negative about your project. You people spend a lot of time/work on it.
        Just missed the ‘hack’ part.
        But i want the hacks! The parts made by people themself. Or stuff totaly used in the wrong way, so it has a new function. People building a Moonrocket out of Pixiedust, Trashcans and crazy ideas.
        I don’t care if a project is big or small, cheap or thousands of $.
        So nothing special.

    6. I agree nothing new here. Yes, he did put it all to gether, but award winning? well he competed against other students, but real world award winning? I dont think so. If I buy all the parts to make a laser table, can I get an award? nope, unless I was a student

      1. Thats the way machines are designed these days. There’s no use in fabricating all the parts by yourself. For a lot of parts, there are standard solutions available – much cheaper then selfmade and often in better quality. You don’t get the award for buying parts, but for carefully choosing the right ones and combining them in new ways.

        A waterjet built inside a mobile case made of aluminum extrusion sure makes for a hack!

        What bothers me a little (from the video) is the pressure fluctuation caused by the switching between the two high pressure pistons, which may cause inconsistent cuts and faster material fatigue then a constant cutting pressure. Isn’t there a way of smoothly switching the pistons?

        Anyway nice build!

          1. That was a poorly written law that did not convert the US to Metric on a specific date but gradually over time. This caused more problems than it was worth and industry began moving back to SAE. Due to that stupidity, it is not likely to ever cause the US to convert to pure Metric.

            It seems that Washington prefers to create new problems while solving old ones and at the same time not truly solve the old ones. In the end, we end up with more problems than we started with.

    1. The X and Y planes on this system are naturally measured in “Egyptian rivers” of which 1 is approximately 2 kilometres. The flow speed can be pronounced in myriad-miles(the modern Swedish myriad-mile) which is about 10000 metres.
      The Z axis I’m not entirely sure about, but it’s either set in fathoms or mark twain. The latter of course being twice the former.

      1. hahaha loved this. hilarious.

        trust me, i would have loved to use metric on this project. in the states, though, it’s sadly just more convenient to use imperial. McMaster supplies mostly imperial hardware, all of the machines in our shop are imperial, all of the tooling around the building is imperial, etc.

        i look forward to the day when i never have to use a “slug” again. worst unit ever.

        1. It doesn’t really matter! I’m European, I can do conversions! And regardless of units, it’s a proper build.

          Lets just all be thankful that our whole set of measuring units do not change any more, every time we get a new bloody king with various new dimensions to his extremities.

  3. Looks like they could usen an attenuator. Might help smooth out some of those striations you can see on their first cut. Basically just a high-pressure version of those anti-hammer units you can get for your home.

    They may also want to consider adding a second intensifier unit cycling on the opposite phase from the first. Combine that with an attenuator and that should improve their cut quality significantly. Might also allow them to move the head a little faster during the cut, especially if they drop in a slightly larger orifice.

    But kudos to them for putting together a DIY waterjet! I wouldn’t mind having one of those in my garage…

    1. we could have used an attenuator for sure! in hydraulics, people refer to it as an accumulator. and we sure wanted one, but we asked around and the quotes we got back for a 15,000 psi accumulator were well out of our budget. we considered making our own accumulator for cheaper, and it’s something i’m still interested in doing, but for the time being we’re just living with the pressure oscillations. fortunately, it still cuts pretty cleanly! another funky idea would be to have the gantry speed up and slow down in phase with the ~1 Hz stroke of the pump, but we didn’t implement that.

      all of this could be avoided with a better pump, though! ours was single-acting, meaning that the power stroke was in only one direction. a double-acting pump would be a lot better. again, senior design budget constraints…

      1. Well done considering the constraints! The 1Hz gantry compensation is really interesting. I love hearing about the thought that went into projects like this. I’d rather have some meticulously designed monstrosity than something that includes a gun in the design to shoot yourself with, because it’s so difficult to use (or just useless).

      2. Budget constraints do tend to put a bit of a cramp in one’s style, unfortunately.

        Varying the head speed in time with the cycle of the pump is an interesting idea. Your programmer might wind up going postal on you though. Gut reaction says that you would have to tweak your algorithm for each material you wanted to cut, and it still might not work quite right. However, since your gantry is so small and has such a small mass, it might actually work. I’d be really interested to see your results with that tactic.

        A double acting pump would indeed help a lot. That, in my personal experience is the industry standard. I’m actually the maintenance tech at an abrasive waterjet cutting shop, so this stuff is my bread and butter. I’m not necessarily on the initial design end, but I’ve wound up with a pretty solid working knowledge of high-pressure and ultra high-pressure pump mechanics, having been in charge of servicing three of them for a few years.

        Like I said before, kudos on putting this thing together. The industrial ones are big, expensive and can occasionally be a royal pain to service. But if you guys decide to open source this idea, anybody with a bit of spare cash and some technical savvy can knock parts out in their garage, which is profoundly exciting. Good luck taking this thing forward!

  4. Will it cut Art glass? This type of glass is used in stained glass art. I get it in 12x12inch square and Avg. 1/8 thick, depending on surface texture. I see your jet will cut metal, plastic etc…

  5. First of all congratulations for the low cost machine. It is nice to see clever people in the pressure business… Maybe I am out of place, but we manufacture an industrial pure water 40000 psi cutter for pastry. Its lowest version SELLING price is in the 69000 euro here in Europe. 16×24″ table. We keep looking for ideas to make it cheaper. http://www.mttec.com ideas welcome! 6 years ago it was much more expensive, but we developed newer models with price in mind, Regards

  6. Adam,
    I am looking to cut out organic curves and shapes for jewelry designs. Most cuts would be for a 1/8″ sheet of silver or thinner. Do you think this application would work for your system? Are you selling these machines? Selling the Design guides and specs? Or are you going to give the information away for free as some have stated above? In any case I would be interested in hearing from you. Thank you.

  7. Adam,

    I would love to buy this water jet cutter off you so that I can use it to help my jewelry business grow. Right now u am sawing all my pieces by hand with a coping saw and your water jet cutter would increase my production 100% per piece. Please contact me asap.

  8. That’s a lot of criticisms for simply making things to well!

    Nice work. A lot of people are keen to have a waterjet cutter and that includes me!

    I was thinking of ways last night, & a big piston did occur as the most straightforward way to go. The other thing I’ve thought of is the 2 stage pumps in modern common rail diesel engines. These are from 15kpsi up to 44kpsi, so are up to the job, at least in theory!

    1. Now I have a wifi connection I’ve just watched the video.

      Brilliant work. A small format machine like that would be incredibly useful for a small fabricator, all the way down to a hackspace or individual.

      To those whining above that “it isn’t anything new”? I’m going to guess it is sour grapes. This is a hundred times better than a small tweak to a RepRap gantry.

  9. Great work! We use those pumps at our shop for pressuring up blow out prevention systems to test them for oil and gas wellhead work. It’s a lot of power in a small package and a great choice for this machine. I may have to drag the test trolley home and run a line to my 3D printer!

  10. I was fascinated to read of Adam’s work. Great job. I read all of the above comments and want to add that there is a low cost waterjet machine available that you can put together yourself.

    WARDJet has just started selling a “”KIT” at a much lower cost than the Emerald waterjet that they sell for $125,000 (the kit has the same American made parts but costs $65,000 for a 2×2 and $75,000 for a 5×5). Still a hefty price but cuts virtually any material. I know people who use it for knife blanks, plastics, , rubber, foam, composites as well as the metals you would expect.

  11. A low priced waterjet cutting? A dream for lots of small business out there. They can start produce and carve small things themselves to sell later on their own. Certainly with this kind of development, we will see much more reliable equipment in the market. I am waiting Adam!

      1. FYI, there is an issue with your website. “The server at tinijet.com can’t be found, because the DNS lookup failed. DNS is the network service that translates a website’s name to its Internet address. This error is most often caused by having no connection to the Internet or a misconfigured network. It can also be caused by an unresponsive DNS server or a firewall preventing Google Chrome from accessing the network.”

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.