Hydro: The Low Cost Waterjet Cutter

waterjet

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.   

Comments

  1. Zee says:

    That pump-piston thing is the magic and it’s amazing. It could have a lot of applications.

  2. Kern Padde says:

    video not available @ germany because of SME and GEMA shit
    but nice idea, how many PSI / Bars ?

    • Sheldon says:

      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).

    • erniejunior says:

      Try ProxTube to conveniently unblock the GEMA shit. Works quite often for me (from germany too).
      https://proxtube.com/

  3. Carlos says:

    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”.

    • I don’t see why they would. There’s some serious bank to be made from this.

      • Drake says:

        Open Source != not for profit. You can still make bank off of open source products.

        • Dax says:

          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.

          • SATovey says:

            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.
            Sigh.

      • macona says:

        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.

  4. I wish there was more details about the pump and cutting end. Sources/part numbers/costs would be great. The XY gantry is the easy part

  5. Elias says:

    The video is available on vimeo, too

  6. NotMe says:

    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.

    • 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 ;-)

    • James Hobson says:

      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.

      • Adam Libert says:

        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!

        • Hello Adam,

          very impressive project.
          Is there a readable version of your presentation poster to be found somewhere?

          Would love to find out more about the performance of your machine & the problems you had.

        • James Hobson says:

          No problem, it’s an amazing project! An anonymous tipster sent us the link!

          What are the future plans for it anyway? Opensource or kickstart — I’m interested!

        • Hack Man says:

          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?

    • I thought the same, buy parts and putting them together is nothing special. I really liked more information about the water jet parts. The gentry is nothing special since the repraps are everywhere.

    • formatc1702 says:

      Yes, I could have built that easily. Probably, so could you!

      BUT: You didn’t! Neither did I! He did, and it’s awesome. Respect!

    • voxnulla says:

      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.

    • Then why, please tell me, is apple so darn successful?

    • JRDM says:

      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.

    • Adam Libert says:

      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!

      • diydsp says:

        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.

      • NotMe says:

        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.

    • JSon says:

      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

      • brassomat says:

        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!

      • Jeff says:

        Nothing new? Please show us your (or ANY) compact waterjet cutter build.

  7. Jerome says:

    The pump seems to be a Haskel-Pump, we have a such one in our isostatic press (1000bar).
    http://www.haskel.com/Haskel/en/Products/Pneumatic-Pumps/Liquid-Pumps/-2-HP-Air-Driven-Pump-Models
    I woult estimate it to be more than half of the cost of the cutter. And you need tons of schop air.

  8. Pretty neat setup. I wonder what type of life they get out of the air driven pump. I’ve found those need rebuilt on a fairly frequent basis compared to other types.

  9. is it too hard to use metric system?

  10. 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…

    • Adam Libert says:

      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…

      • 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).

      • Ben says:

        Terrific work Adam! Really impressive and this is bound to have a lot of real world utility. Cheers for engineering!

      • 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!

  11. Owen White says:

    Adam,

    congratulations this is fantastic. Not complaining but the kerf diameter of the cut seems fairly large (compared to a laser for example) do you think there might be a way to decrease its size?

  12. RDZOMBIE says:

    Well done, though I must say I’m a bit disappointed, I was hoping for a 30k plus PSI DIY pump

  13. deadlydad says:

    Bravo on a well done job! I wonder how long it will take Bre Pettis to contact you. :grin:

  14. anomdebus says:

    FYI, more information found here: https://sites.google.com/site/meamwaterjet/

  15. Jeremy @ TMC Water Jets says:

    I find it funny there are people above actually criticising this. It looks pretty damn good to me.

  16. Robert Elber says:

    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…

  17. Zig says:

    Adam,

    Are you guys working on making a garage sized (both in size and economy) model to sell to the public? I would be interested in such a thing.

    Best,

    Zig

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