Homemade Jet Unit 3D Printed, Testing!

The 3d printed jet pump gets tested out a few times and repaired but ended up using a longtail motor setup which worked way better as the twin 2 stroke motors were under powered .
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[@erombalski]

Until recently, I assumed those longtails were something that got cobbled together out of some necessity of available parts. Recently I learned they are purpose built to offer a ton of advantages for shallow situations with lots of weeds or obstacles to go over/around. They are also dead simple and relatively cheap. So, armed with that new found respect for the design, I'm keen to see someone like you figure out how to make the most fun use out of it. Hunting down the limits of speed, control, efficiency, and perhaps a quieter exhaust, would all be cool things to see. Cheers.

[@DktheWelder]

They are awesome and simple but a bit awkward to control. I would like to quiet it down a bit

[@AtimatikArmy]

@@DktheWelder Maybe delete the muffler to offset that slight power gain by running a straight down pipe just below the water (deep enough to muffle but not cause significant drag. Maybe add a simple horizontal "surface plate" at about the point the pipe meets water surface to help prevent cavitation of the exhaust at exit point. (in other words, to keep te exhaust beneath the surface long enough to dissipate some sound without having to run the pipe too deep into the water? Just brain storming. Water is a great muffler and it's right there...

[@DktheWelder]

@@AtimatikArmy I have tried that before running the pipe into the water with those motors really robs the power , an outboard runs it through the centre of the prop where the water is turbulent so it pushes through it better I guess, there will be a way to do it though

[@AtimatikArmy]

@@DktheWelder what about a simple water pickup (prolly no pump needed) and have the line run to a silencer like a dirt bike but without the fiberglass packing?

[@LostCloudx4]

Here in Thailand I live 150mtrs from the beach, Every morning the noise from the fuckers wakes me up even with closed condo and aircon on lol... they have no mufflers at all

[@andersson.l.e]

Your adaptive skills are amazing. I like your determination to make it go. Like your video as usual.

[@BruceLyeg]

It moves pretty good with the longtail on it! Not getting chopped up by the propeller is a good idea. Happy Birthday to your dad

[@RCPMK]

Super cool project. A couple near our cottage in the late 70's had a pair of Surfjets they would cruise on together..always wanted one. I love your catamaran too!

[@CMBProjects]

Wow that's an amazing build! Great work! I also use those engines to make RC cars and they work pretty well!

[@dellingerboysadventures3954]

Your Dad is badass! Tell him Happy Birthday. My dad is the same way. My dad is always there for when I test and work on my crazy projects like yours. Love your channel.

[@rickbrooks1608]

Honestly I think you've hit gold with this setup. Along for the ride whatever your next idea is. Cheers🥂

[@marcdixon4292]

I think you should do what ever puts the big smile on your face 🖖

[@johncostello3666]

There’s no distance for the persistent love your work mate please keep it up for all of us Bucket heads👍👨🏻‍🏭

[@simonjeffery6836]

I truly enjoy your channel, learn with a giggle, love the channel and keep it up mate cheers 👍

[@azlongtales]

Koolest video demonstrating why longtail mudmotor are the best!!!!!

[@DktheWelder]

The longtail is just better it way more efficient you can carry the board easily then put the motor on in the water, then not have to worry about sucking stuff up , can change the prop in about 30 seconds, and cheap and simple

[@azlongtales]

@@DktheWelder posted up some clips of this on our Instagram with a link to the video and put you in a playlist on our channel. Koolest stuff ever

[@robertmckay694]

What a project! But of a bummer the power was low but what a great save and what a great day! Wasn’t there but felt the fun family vibes!!!

[@kellycostello2930]

My thoughts were that’s awesome and please don’t fall off, nice job man keep it up!

[@ncwarrior62]

Daniel your awesome mate ya never give up that’s why I love your videos! Looks like a lot of fun!! Enjoy n have a great one brother!!!

[@ncwarrior62]

Mate I would go the electric long tail route plenty of torque high speeds possible great compartment storage for batteries!

[@YML1357]

always put a smile on my face

[@liamunderwood3115]

hahaha your builds are awesome bro. always keeping it real and i love that the build just went straight to thai style long shaft.

[@jthoney]

Man I really enjoyed this video Daniel!!

[@DktheWelder]

Thanks Joel I need your advice on some other videos!

[@AfterThePavementEnds]

Electric long tail sounds like a blast! Got me thinking!

[@TheSmallEngineShed]

Looks like so much fun with the Honda clone engine on it. Great job.

[@EasyFold007]

I don't care what direction you going to head...just have fun doing it...come on you can do it we are rooting for you :)

[@simonbertioli4696]

Great fun... through all the mishaps..but they don't matter..enjoy the time with your dad... priceless.. I know, l am the same age. Simon a Brit in Spain 👍

[@DktheWelder]

Thanks, I am lucky to have such a great dad and he is always up for some fun

[@simonbertioli4696]

@@DktheWelder thanks. I know my son's feel the same. I miss them..we used to have so much mad silly fun... All good for the soul. Did not mean that in a religious way. But do have fun with dad. I missed out on mine with my father..but that's life.

[@deegee5702]

awesome build man, pity those little motors weren’t up to the job, looks like great fun with the long tail. keep up the great work and videos 👍🏻

[@joshuaharrison9331]

motors were fine he just didn't tune them at all ...

[@moshe778950101]

The propeller inside the jet unit is terrible. The only thing such a propeller does efficiently is destroy efficiency. The blades should be much smaller. Propellers don't push water like a screw. They generate lift. If you change the design you will get better performance. And it will be more resilient against seaweed.

[@coreyperris3688]

Bloody awesome mate

[@PatrickRich]

Bringing back memories of a jet surf i had. Disappointingly slow but an experience

[@iamkian]

i was talking about this 3d printed fuel cap some videos back 😕 and happy birthday to your dad.

[@DktheWelder]

Yeah I remembered someone saying that it only happened after that first test I guess from all the fuel sloshing around 👍. Do you know if that tpu filament is fuel resistant?

[@fazyluck]

Bro! That hauls with the longtail! 😂! Sick!

[@DktheWelder]

It has more in it too , my dad was going quick too!

[@littlelifters7543]

What a cool project, so much learnt. Remember to push away if you fall off so the blender doesn’t get ya.

[@DktheWelder]

Yeah it is a bit scary with that prop behind chopping away!

[@bluegrassmagee8697]

Yay! Super Outboard Surf/Ski Love it & glad you're not quitting, I just found you LOL! Would like to see more catamaran sailing with your dad too. 😀👍⛵️💖

[@azlongtales]

Such an awesome video!!!!!

[@handyandy345]

Love that beach was thinking of taking the kayak there yesterday.

[@gyffjogofl7676]

Awesome video!

[@blakebennett9904]

Another great video ! Good effort

[@bensprink9943]

I've been following this build for awhile, glad to see it on the water. I kind of expected that it would end up being underpowered. Jet drives are horsepower thieves. Maybe do a surface drive prop setup with the same twin engines, sort of like an rc boat.

[@gafrers]

Great, looks like a blast.

[@pete3897]

You do you bro, I'll enjoy watching either way! Just keep plenty of those gold welding tips in there like the stainless bolt trick. Shout out from down Nelson in the SI

[@Superb_Owl80]

Beautiful location!

[@Razoot]

Didn't your mother ever tell you never to take a hoverboard over water unless you got... Oh wait nice one dude.

[@alex4alexn]

you dad is a cool guy, props to him :)

[@fletchercho6514]

More motors! I would like to see the firewall moved forward and another motor or two added to get the jet working. I think stay with the jet and just change the jet/motor until it works. Love the effort mate! Cheers.

[@DktheWelder]

I did think about that add 2 more motors haha it would be pretty hard on the crank of the last one though

[@angelojones2554]

yes I agree I love jet surfing

[@MicRuLerZ]

@@DktheWelder why not adapt a 15hp outboard powerhead to work horizontal in the board

[@DktheWelder]

@@MicRuLerZ that would work I think !

[@lloydrees7674]

Great vid and channel mate, love your inventiveness and humour. If you ever need Hydraulic parts to hack or experiment let me know as I’m always throwing away blown hoses and fittings

[@DktheWelder]

Ok thanks will do!

[@benschlack5814]

Your Dad is awesome 💯

[@clint91x]

Kawasaki js300 motor would work but is pretty big. I would look at a 2 stroke 85cc off a a motocross bike. They're in that 15-20hp and you could ditch the transmission and get the size down to what you need

[@honeyy79]

That was awesome!

[@Jessen_2002]

Hey iam new to the channel, cool project! You sparkt my intrest and earnd my sup and like. Keep up the great work dude

[@_coffeeandcigars]

nice move on the polisher ;) smooth as

[@sonofstinkfoot9551]

80CC 2 STROKE DIRT BIKE MOTOR LOCKED OUT IN 5TH GEAR THERES YOUR JET MOTOR !. GREAT VIDEOS!!.

[@SvendsenWorks]

While the first motor setup was underpowered, it still looked super clean! The 2nd might not have the looks, but at least it's got the fun!

[@kriscsandli2147]

A friend made a similar board with a powerful electric drone motor and it worked great with plenty of speed.

[@DktheWelder]

I actually just got two big drone motors that I’m putting in a mini jet boat so that should be fun!

[@MikeAnderson-oh9po]

Your dad is awesome!

[@westie4ageturbo.749]

Soo Huge effort in r&d with many many attempts with the two strokes and no luck, Cobble together a solution for the hell of it and it just works! Hmm Great effort!!

[@DktheWelder]

I know the longtail works great with no effort

[@meettheworld6241]

DUDE!!! THAT IS TOO FKN AWESOME!!! I'VE GOTTA MAKE MYSELF ONE OF THESE

[@DktheWelder]

The longtail surfboard? It works well I have used it a few times it is fun

[@azlongtales]

That longtail 🔥

[@udecity]

You can also use a powerful brushless electric motor for it

[@DktheWelder]

Heaps of other people have done that I want to try something different maybe electric longtail

[@pennysgarage]

Nice!! Just extend the controls and you could run a longer pull start cord up the control handle too for big water restarts!!

[@curvs4me]

Air intake will greatly restrict the flow. The heat from the exhaust pipes will cut the power way down. Maybe a pump and jacket the exhaust and a small bilge pump at the rear? Chainsaws go up to 90cc if you can find some used and rebuild? Jonsered or Stihl. Clearance for the impeller makes a big difference in efficiency. Race units are machined running ceramic bearings.

[@ADLautomaticos]

CONGRATULATIONS I'M DOING A PROJECT WITH A 135CC MOTORCYCLE ENGINE, BUT HERE IN BRAZIL EVERYTHING IS MORE DIFFICULT TO ACCESS SOME TYPES OF MATERIALS BUT WE'RE STILL STRONG, HUG

[@AlOne-xg6dv]

With the catamaran, the long tail and motor could be installed at the front to shorten the full system

[@tylerwatts1004]

First and best long tail surface drive NOT jet board 😀 awesome Dan. Shame about the jet drive but nice that you can swap between both options. Search for a powerful 2t motor but I love the electric long tail idea. Batteries inside and dry, motor outside. Big RC outrunner motor with torque for the surface prop but plenty RPMs. Easy to mount also, just need a bearing housing to support the drive shaft. What about a 125cc kart 2t motor? No gearbox, small centrifugal clutch or not, and up to 40bhp if liquid cooled monster! Only might be pricey... Be great to see the jet drive running.

[@markdodson6301]

The hours put into this project was crazy! The dual engine setup was crazy, wish it worked the way you had envisioned. You could throw a js300 motor and pump drive train in there and let it rip. Or go full send and somehow get a 701 motor and 144mm pump in there for some MACH 1 speed. Seeing a cr125 motor in there would be crazy too, probably enough power to push it, somehow delete the gearbox

[@DktheWelder]

Yeah the whole idea was to be able to make something cheap. A cr125 would be awesome!

[@officialmysteriousrider130]

​​@@DktheWeldermaybe use the duel engine setup for a stand on petrol scooter goped project & you can actually buy different CVT drive gearbox for them with bigger sprockets fitted

[@JoeKyser]

I would play with the tolerance of the prop. Ive had issues with that.

[@MasterBo39]

Consider: Much larger intake funneling larger volume of water x 4. Impeller longer x 2. Then a 2 to 1 RPM gear for the impeller. or something like that. Bo.

[@DktheWelder]

Yes thanks 👍

[@hamishhill]

Xzibit: Yo' dowg we heard you like boats so we put a boat on your boat so you can boat while you boat. hehe its a bummer it didn't get the speeds you wanted on the jet unit but stoked you saw it through tull the end and the long tail looked like wicked fun. since you've already got all the set up for gas engines what about the worlds first hybrid jetboard?... could do the electric drive and then use the engines you have with an alternator to power it... pretty sure with all the extra weight it wouldn't be as fast as a normal electric jet board but it would be 1 of a kind for sure. great work as usual and look forward to seeing what you come up with next.

[@DktheWelder]

X to the Z would love the hybrid board ! Sounds tricky to me

[@iamkian]

Do you mind sharing the STL file for the stop button ( 00:08 )? We might have some use for it too.

[@DktheWelder]

Yeah ok I will think find it . Remind me again later I will try get it to you after work

[@JansVanlife]

Nice Board, I'm also building a Jet Board :) I'm using a 100cc 2 stroke 25HP kart engine. I just have to add an electric starter and manufacture a reliable shaft coupling. My Jetdrive is also 3d printed 89mm.

[@DktheWelder]

That would be about a perfect setup ! And electric start would be great, is it water cooled? And where did you get the motor?

[@JansVanlife]

@@DktheWelder It is a KZH 100cc engine and yes the engine is water cooled.

[@JansVanlife]

@@DktheWelder I bought the motor used on ebay.

[@DktheWelder]

@@JansVanlife ok thanks a lot I will look into it👍

[@AlOne-xg6dv]

And what about the noise ?..

[@battlebong869]

Would a 150cc-250cc scooter motor mounted on back with a chain drive to the jet work?

[@testandoxeon1642]

You can customize an 80cc 2t bicycle engine (change the stroke to 55mm) and use the ms660 (56mm model), ms070 or ms088 cylinder to achieve volumetric capacity above 135cc. You can improve compression ration to 11.5:1 or above and use E85 (85% alcohool and 15% gasoline). Here in Brazil exist a motor 132cc 2t from yamaha rd135 with impeller 93mm spin 7800 rpm is a good motor to motorized surf board.

[@DktheWelder]

O wow that sounds cool ! How do you know this? I’m interested in the 80cc bicycle engine modification!

[@kyleo1236]

You should put the 2 stroke engines back in and run a driveshaft out the back and stick a prop on it. May not be as fast as the longtail but would be more tidy.

[@captnjaygreybeard6394]

Can you make some kind of belt drive from the engine shaft to a new lower propeller shaft, so that the prop shaft is lower? this would shorten the distance to the propeller. Anyhoo, looks great as is, looks like fun, cheers.

[@ECL..]

Could you use a 20hp 2 stroke motor off an outboard? That way you could strip it down and make it flat enough to fit inside the board.

[@mudjamz75]

Not sure if you said but ditch the jet and use the motors for a built-in long tail. Steering I guess would be the tricky part. Or would output be too low?

[@nocare]

I have always wondered how much performance a longtail would gain with a constant speed prop. You would lose survivability in a prop strike but it will be a cool experiment. For anyone that doesn't know a constant speed prop varies the prop blade pitch to constantly hold the engine at the desired RPM value. This means you can be at peak power no matter how fast you are going and thus maximise efficiency thru a wide range of speeds and generally obtain higher max speed. In a way it acts like a transmission for prop driven vehicles like boats and airplanes.

[@azlongtales]

Stainless steel version of those props never break and we hit stuff with aluminum ones all the time without issue. The props also change out really fast and are inexpensive

[@nocare]

@@azlongtales They make constant speed props for longtails??? I was unaware do you have links to these? I thought they only made fixed pitch props because they are cheap and require no extra mechanical systems such as a drive motor and linkages.

[@therealdonfito7385]

If u use the aluminium as a mold u can make it from fiberglas way lighter and there is a bigbore kit 70cc for the minibike engine come.s with bigger carb greetz from the Netherlands Love your videos

[@kieren7763]

A few options that I could thinks of would be either a scooter motor with a big bore kit keep the gearbox on and there pretty quick or look up the rovan baja 5b rc cars those guys port them like crazy and play with crank case volume by filling the crank case with jb weld and get around 6 to 8 hp out of little weed wacker motors

[@gilliesiut2332]

I’m glad you said that’s sketchy before I did lmao

[@testandoxeon1642]

Hi, great experiment and fun. Search in grab cad propeller 147x309mm could you print, reinforce with carbon or fiber or casting and test to see if improve the performance? Thanks.

[@durbeshpatel3047]

You might get extra thrust if you could route the exhaust out the jet novel as well. Mixing the hot exhaust gas with the ejected water

[@mattl6376]

Jetdrives pressure to like 150psi and an exhaust is like 5psi. You would gain no power and just flood your motor with water.

[@Dutcharmytent]

Can you show us how you made the long tail please. Interested in the shaft drive side.

[@DktheWelder]

I didn’t make the longtail it is an sps kit you can buy, but I have made another longtail shaft for a chainsaw motor on my channel 👍

[@Dutcharmytent]

@@DktheWelder cheers, I was sure you extended the shaft and added a prop, will watch again to see what I missed.. What you do is astounding. The 3 d printer parts are so interesting alone.

[@shaunandsqueak]

Farkin cracked me up man ! lol least ya have a fair idea what sizes engine/prop speed flow etc... for board two point oh!!

[@tacotheelmaco2489]

you could strip out the powerhead of an old 2 stroke outboard, that would probably do the job :), tohatsu's m9.9d2 are really quick for their horsepower or the 18hp, their 25hp can be tuned to 32hp very easily. or you could do the yamaha 30 hp 3 cyl, very good motor.

[@petermines3575]

Awesome

[@ISupportTheCurr3ntThing]

Could you do a break down on that prop shaft and little briggs you got? would be awesome. thank you

[@DktheWelder]

It is just a longtail kit that you can buy and just bolt a Honda clone engine to it super easy. Just google sps mud motor it should come up

[@ISupportTheCurr3ntThing]

@@DktheWelder will do, thank you!

[@toddrichardson2854]

It's not stupid if it works. I do prefer the jet tho, yz250 or similar?? Maybe needs more of a "V" in the hull for stability at 20 knots. Love it either way 👍

[@gabbermaikel]

when do we see the 2 longtail motors on the catamaran btw?

[@DktheWelder]

Haha that would be cool!

[@aretardridesmotard6128]

The long tail is great, such a shame you can't fit a bigger motor in there. I wonder if cutting the gearbox off a 2 stroke dirt bike motor would get it done. There's not much left of a yz80 after deleting the box and clutch pack.

[@DktheWelder]

An 80cc mx bike motor would be great a 125 cc be better

[@theideasman6018]

Looking good man. You could put that long tail motor at the front an sit at the back. Seat , rudder , fun. Also. Modify your car to run on cng it's cheaper

[@DktheWelder]

I have kinda done that already on a little boat build

[@kieranshelley8495]

could try a offset flywheel key to increase the timing advance on the engines too bring the revs up more, or even a planetary drive

[@kieranshelley8495]

rockit key for goped scooters is what i have in mind they use zenoah engines

[@dirtfootracing8788]

Always thought a powered hobie cat would be fun

[@DktheWelder]

I would like to mount the longtail and still be able to sail as well would be cool

[@natefessler3961]

Electric longtail would be dope

[@pauljs75]

Was waiting for some guy on a paddle board to show up and pass him while trying to get the jet pump setup to work. (Still seems like some issue with the pump more than the motor, since it sounded like it was keeping up revs.) Good effort though.

[@bloodsweatandtearsforeverl9833]

I I think it was just a exaust leak for the first engines, I seen smoke pouring out of where your feet were, the carbs were probably not getting enough air

[@dallas749]

had like a tear in my eye when the 2 50ccs didnt work, maybe a ktm 50cc or a chainsaw motor would be better. Carbon fibre reeds and a ported cylinder could add a wee bit but may not be enough. All in all well done bro, the board looks awesome 35km is fast.

[@DktheWelder]

I know I was annoyed they didn’t work , need more power!

[@dallas749]

any chance the hydraulic hose was slipping? aww no i already bought a gold motor =[

[@DktheWelder]

@@dallas749 na man I’m in the shed right now looking at it is still on there super secure

[@dallas749]

@@DktheWelder I dare you to go electric 🤔🤔

[@FAKE-NAME]

is it possible to modify the jet intake so it has a stomp grate to clear it out and prevent stuff from getting in?

[@DktheWelder]

Yeah I could. The board is easy enough to reach under , a grate might have helped

[@FAKE-NAME]

@@DktheWelder i was thinking some fixed bars across intake but spaced so other bars fit in between and have the non fixed ones hinged at the front with 2 vertical bars at the rear that go up through the board to a stomp pedal that you step on to clear and it would be on springs to pop it back up and keep it up when not being stomped down.

[@DatBlueHusky]

id say make a smaller jet unit, it might be better since through it might put out less thrust but at least the motors can rev up

[@onbedoeldekut1515]

You could make some small hydroplanes for the cat's pontoons and the speed would raise it out of the water, greatly lowering the drag co-efficient, you could probably even do something similar with the board as well. I'd like to see potential hybrid vehicles that could cover many bases, as different power sources provide different torque ranges which are more beneficial for different tasks, not always demanding of power. You could even use natural power with small balloons lifting sail kites when there's no 'low' wind.

[@DktheWelder]

Do you mean hydrofoils? I have been thinking along those lines it would work well with the longtail motor, and I have been thinking about using a kite as well but they aren’t as efficient as a sail

[@onbedoeldekut1515]

@@DktheWelder oops! You're right! Hydrofoils are what they are, hydro-planing's what they do! I speak quicker than my brain sometimes.

[@bamoblivion8614]

3d printed parts have there limits but when you've reached those limits with plastic it's time to use those 3d models to make stronger parts like PLA casting in aluminum

[@djtutty76]

Hey mate. Very cool project. Makes me think i need to get a 3d printer and develop some skills like you have. Im a little disappointed you are giving up on the two-stroke jet unit. I hope you stick with it some more. To me it doesn't seem like a lack of power. It seems more like the jet unit is slipping a lot. On a full-size jet boat impeller design and the clearances between the outer diameter of the impeller and the housing (wear ring) surrounding it make a huge difference to the performance of the unit. Think of the jet unit as a pump rather than a propeller in a tube. I am currently building a small hull and intend to use the same engine you have with some type of homebuilt jet unit.

[@DktheWelder]

I wish the 2 stroke would work too , It would probably work with a propeller but jet units are pretty inefficient and power hungry. I am building an electric mini jetboat at the moment with heaps more power so hopefully that works

[@harryburford6629]

keep as is they have them in vietnam go to mr ho they race them they put on deisel motors with turbo they are fast to mabey make a boat and try a deisel ,, a wider boat and 20 hp never no,, good luck and great video

[@CorndogBrownie]

Electric long tail I think would be a riot

[@limitlessbuilds]

Why not use a small 125cc dirt bike motor or high hp kart racing motor? Should be able to get those around 20hp for an older one. Would love to see the jet working as intended, but still awesome this way too!

[@leighharvey9150]

I reckon it’s the impeller. I reckon you should try different impeller designs