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@@gregschweers8124 No, I don't offer 3D printing on demand. All I can suggest is to find a local 3D printing company which would print this for you.

@@Need_more_free_time Yes you are right, good tip

Hey, This is a long-term project. Since this video (7 months ago), I did multiple tests in very hard terrain. The chassis has amazing potential and I am very happy with where this design is going. The whole drivetrain - the gears and gearboxes - still needs great amount of work. I did 2-3 versions already, still not how I want it to be. It is specifically difficult to combine 1) excellent reliability, I want to make the drivetrain unbreakable and eventually stall the motor rather than break gears 2) comfortable accessibility and easy disassembly of all parts independently. I know what to do for the next iteration and have solutions in mind, but since this video I haven't had time for such a big redesign. Apart from massive CAD work, every new iteration requires printing and assembling 8 gearboxes. Currently, my other projects have priority - new jetboat related development, and a bachelor thesis:) I will absolutely get back to this when it is possible, which could be next summer. It's been a year and half since this project started, maybe it will take a year and half to finish it. You will see it here when it happens:)

Yes, you are right, I hid the video. After I released it, I had some more thought around it. Right now the M-Jet Development is my only side job while I am studying. I really like it and I would like to continue. In order to keep my position on the market and my income, I can no longer give away all of my knowledge and methods. Anyone who comes to design jet pumps after me can copy what I do without having to spend those 5 years to figure it out as I did. As you can see from my videos, I like to share stuff. However, by doing it, at this point I am just putting my job in danger. Therefore I need to find a balance between sharing everything and keeping some tricks for myself. I will continue to share the results of my work; probably no longer everything which led to them. Thanks for understanding.

@@mjetdevelopment Fair enough, thank you for the info you have shared so far, and I truly wish you success. 👍

@@mjetdevelopmentCompletely understand your reasoning. It’s too bad though, I’ve been learning so much from you and really enjoyed that last video. It’s been very interesting following your progress. Keep up the great work, we all appreciate your efforts 🙌🏽.

BTW Stepan, even if you no longer share the internals of your data logging experiment, I would appreciate if you could at least validate how far off are my calculations in the spreadsheet I left at the RC Groups forums 🙏

@@geekmidget Yes I will take a look.

@@darkokatrasnik9810 The KV is a bit too high, 2400KV would make a good 3S setup. You can still run 3S, maybe 3S 2400-3000mAh but pay attention to how hot the ESC will get. Lower KV would be better and then you could run 4S for example. Please follow the Supersprint manual for the most detailed up to date information: drive.google.com/drive/folders/1f-epKNBlcqGcuJU5rGvYQleL7ayPnrRe?usp=sharing

@@rafc843 Thanks for your understanding, that aliexpress sellers who violate my design rights should not be supported. Nevertheless, things have been going well for me lately, so no worries. The M-Jet Development is continuing.

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

@@petervenema9628 Most importantly, choose the filament that works the best for you, you have well tuned settings for it and your printer prints it well with good layer adhesion. I used ASA this time. PLA worked for me well in the past too. People use all different materials mostly with success.

Yes good tip:)

@@allenarceneaux The rollers go into the main big printed bearing, in the video it's yellow. Try googling "crossed roller slew bearing". In case there are more questions, feel free to send me a direct message on CGTrader: www.cgtrader.com/designers/m-jet-development

@@zohrabmamedov5446 You could try scaling it to 200% or 300%. Then theoretically, performance might be sufficient. However there is so much trouble with the upscaling process: If you upscale it, all bearings, shafts, hardware will upscale too, possibly resulting in non existent hardware sizes. Imagine 300% M3 screws -> M9, pretty much doesn't exist. The mount for motor and servo will no longer be compatible with anything. Tolerances might get screwed up randomly. Overall - the upscaling process would require great effort. Then, trouble will come as you will need enermously powerful electronics to spin the upscaled pump. Torque scales with 4th power of size here. 2x size -> 16x torque. Power consumption scales with 3.5th power of size. 2x size -> 11x power input and motor wattage.

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

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

@@mjetdevelopment thank you!

@@lots_haus The Supersprint has self righting. When built correctly with components placed according to the manual, it will always flip itself back to the correct position.

@@Debraj1978 I don't find it that simple to continuously dissipate 1000+W into anything. More importantly, I need to be able to adjust torque. I assume it could be possible to adjust the DC resistance on the second motor, but then it would require an adjustable resistor? An adjustable resistor capable of 100A.

@@NeverMind0113 No, I don't sell any physical pumps. You can purchase the files and build them yourself. If you don't have a 3D printer, you can ask a company to print the parts for you.

@@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.

@@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?

@@nej113 Yes

@@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.

@@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.

@@burner8126 It's barely enough for the full width of the hull. The hull itself is 20cm wide at the widest point. For more comfort I would recommend a wider cloth, alternatively you can use 2 overlapping pieces.

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.

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

@@scoty7392 Hahaha maybe

@@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.

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

@@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

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

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.

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.

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 🖕🙄🫳🎤

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

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.

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.

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

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

Or a Jet Surfboard 💓

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

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

​@@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.

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

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.