M-Jet 30 Update & Full Build / 3D Printed Jet Pump

[@mjetdevelopment]

M-Jet 30 files available for purchase: www.cgtrader.com/3d-print-models/hobby-diy/other/m-jet-3d-printable-jet-drive-for-rc-boats Hardware and electronics kit by RCPrinter: rcprinter.com/products/m-jet-30-pump-build-kits

[@airevolution926]

This is a great pump with way more power than I was expecting for its size.

[@jasonscutella2549]

Very impressive mate. Enjoying our first build with the supersprint thanks

[@cameraman1234567890]

Love your designs! I personally use two of your two-stage MJET 60's for my electric surfboard. Only modifications I've done to it is increased diameter for water cooling and a second large water pickup for better heat dissipation

[@NineStars75]

Very great conception

[@AKRCPRODUCTS]

so cool. looks amazing.

[@arif_fadillah_]

great design, love it

[@WJdriver000]

Hell yea ! You should design one for a kayak. Like a 200mm. Lol you’d need a Jupiter resin printer.

[@SpencerGaming7580]

For 200mm you would need at least a over 100horsepower Motor Dude

[@WJdriver000]

@@SpencerGaming7580 is that how it maths out ? There’s a few jet kayaks available already and 100 horse isn’t impossible. But i agree that’s a bit over kill

[@SpencerGaming7580]

100mm is more than enough for a Kayak, it also mostly depends ob the Form of the hull. Kayaks are Not really designed to Go plane and have a lot of drag, so you would Just waste all that Power unless you Take a Kayak Like youngsters Jets If you know him. When the Jet Diameter gets bigger the Power needed to operate IT properly rises exponential

[@BassforFun]

You answered my question that was if you can put the m-jet 30 into the Valkarie, thanks!

[@MrShaneSunshine]

3d print some soft vice jaws so you don't damage the metal parts with the vice eh! 🇨🇦

[@mjetdevelopment]

Yes good tip:)

[@Ghosty-RC]

I LOVE it!

[@nej113]

Hey! Could you please explain the equations you showed in an earlier video to calculate input/output efficiency? What do the symbols represent and what do I need to measure? Input is easy of course but I’m a little confused about the output power calculations.

[@mjetdevelopment]

@@nej113 I measure thrust of the pump. I also know area of the exit nozzle. From these two, I can calculate mass flow. See, Thrust T, mass flow m, volumetric flow Q, nozzle area S, exit velocity v, density Ro, metric SI units: T = m*v T = Ro*S*v*v Therefore v = (T / (Ro*S))^0.5 And m = T/v Then power output P is equal to kinetic energy of water which flows out per 1 second P = 1/2*m*v^2 Hope that helps.

[@nej113]

@@mjetdevelopment So you would start with v = (T / (Ro*S))^0.5 as the known variables are thrust, water density and nozzle area? And then go on from there?

[@mjetdevelopment]

@@nej113 Yes

[@mjetdevelopment]

@@nej113 Also keep in mind this is only valid for static thrust test. For a running boat it gets way more complicated and so far I havent managed to fully measure performance of a running boat.

[@nej113]

@@mjetdevelopment Thank you so much! I'm in my final year of school before university and we have to do some kind of bigger project. I've been watching you since the original M-jet 30 and I thought this was a perfect opportunity to try and design my own jet drive. My plan is to design and 3d print a jet drive and then measure static thrust efficiency (input and output power) and try to optimize it to some degree. You've really been the inspiration for this project so thank you.

[@Bein_Ian]

Do you ever think about going bigger? Kayak size or maybe even regular speedboat sized?

[@mjetdevelopment]

So far I am not intending to build any kayak or a regular size boat, so I wouldn't be able to test such a big pump. But maybe I will have an opportunity to work on a jetski pump or something in the future, I'd like that, yes.

[@dfg1ml]

wow.....klasse

[@Jish79]

Will the part kit from Rc printer work on this pump?

[@mjetdevelopment]

@@Jish79 RCPrinter has a hardware kit dedicated for the M-Jet 30: rcprinter.com/products/m-jet-30-pump-build-kits

[@burner8126]

Do you have a reverse bucket design? I haven't seen one of yours with one?

[@mjetdevelopment]

@@burner8126 Currently no M-Jet pump has any reverse bucket. I don't design them because: 1) The boats can usually turn 180° in place, there is very rarely need for reverse 2) If there comes a need for reverse, it works to slowly spin the motor backwards and drive backwards that way 3) A reverse mechanism would be bulky, add complexity, pars and weight, which goes aganist the intention of a simple and robust design.

[@BassforFun]

what type of battery should i use with the 2150 kv motor and 100a esc?

[@mjetdevelopment]

3S 2400-2800mAh for best runtime. 4S 1800-2200mAh for best performance.

[@BassforFun]

@@mjetdevelopment thank you!

[@scoty7392]

Which is bigger, 30 or 35? What is the thrust difference? I second the request for jet surfboard pump.

[@mjetdevelopment]

M-Jet 35 has approximately 35mm impeller diameter, M-Jet 30 has approximately 30mm impeller diameter. M-Jet 35 has much higher performance potential, depending on the electronics. M-Jet 35 requires bigger motors and much bigger ESCs. The setups I had produced 5.3kg with the M-Jet 30 and 6.8kg with the M-Jet 35, however in those tests the M-Jet 30 operated at the peak of its capability, while M-Jet 35 could still achieve much more if high end electronics are used.

[@scoty7392]

@@mjetdevelopment Thank you for your information. Can you please make M-Jet 50?😂

[@mjetdevelopment]

@@scoty7392 Hahaha maybe

[@wilsonyip81]

Where you guys buy the jet motor?😃

[@mjetdevelopment]

The M-Jet 30 STL files, which you can 3D print yourself, are available for purchase: www.cgtrader.com/3d-print-models/hobby-diy/other/m-jet-3d-printable-jet-drive-for-rc-boats You need to self-source all hardware and electronics, including the electric motor.

[@SpencerGaming7580]

and now a 100mm model of this awesome pump plz

[@mjetdevelopment]

Maybe one day I'll get to developing one for a jetski or bigger. Would love to.

[@SpencerGaming7580]

Or a Jet Surfboard 💓

[@ripmax333]

The 3d printed parts shown here are all in PLA?

[@mjetdevelopment]

This is all ASA, but you can use PLA too.

[@ripmax333]

@@mjetdevelopment but is there a particular reason why you choose ASA? You recommend ASA for the drive unit?

[@mjetdevelopment]

​@@ripmax333 I have good experience overall with printing ASA lately, my printer is well tuned for it, prints fast. It can also be acetone smoothed, which I used to increase efficiency of the Supersprint pump. I also used PLA before for many different builds with good success. I find that many people use many different filaments, and everybody has different experience. Therefore I suggest that you choose the material you have the best experience with and are able to print it in the best quality.

[@Bein_Ian]

​@@mjetdevelopmenthas anyone tried SLA prints with your models?

[@mjetdevelopment]

Yes, it also results in the best surfaces in the pump, getting best performance. Some people succeeded. However it can cause some complications with the threaded inserts, 100% infill ends up heavy, and overall I design everything for FDM. I don't recommend SLA unless you really know what you are doing.

[@dannyjames5582]

Hi Do you sell these Thanks Danny

[@mjetdevelopment]

I only sell digital files, which you can print on a 3D printer: www.cgtrader.com/3d-print-models/hobby-diy/other/m-jet-3d-printable-jet-drive-for-rc-boats

[@thrcvidz5091]

God get over your little pump..anything to try n keep yourself cool... move on.try building something else

[@jerichojoe307]

If you're so tired of it, why are you here 🤔. You could have easily kept scrolling 🤷. But instead choose to bash someone for no reason. He probably makes a butt load off it as the hobby is huge. Not to mention the implications of upscale for full size watercrafts. Let this kid live his dreams and go find some ambition of your own to accomplish something., instead of trying to bring people down cause you have no ambition or ideas that are better 🖕🙄🫳🎤

[@thrcvidz5091]

@jerichojoe307 well considering I m a retired Catapillar engineer who designed the 793 ..biggest haul truck in world...ya ill go get inspired..lol

[@airevolution926]

You didn't "design" the truck, you helped in a large team of people to design a part of that rig. To say you Designed it like you thought of and built the thing yourself is arrogant. Besides how long did it take the team you were in to think of a usable solution and with how much funding. M-Jet Development has made not only a functional unit, but a unit that anyone can make at home with a printer and some basic electronics. His channel is named after the pump he is making what else could you expect, unless you're just ego flexing.

[@Bein_Ian]

You're pretty weird to shit on someone else's hobby like that. Seems like you'd do "anything to try n keep yourself cool..." Try existing as a better person.

[@geekmidget]

It's called perfectionism, something you apparently cannot comprehend 😆