Traxxas Spartan Jet Boat build

[ManDime]

So I thought I would share with yall my jet boat build. I also have it posted on Traxxas forum.

Here's my bare blank canvas that this adventure happens with:



Nothing has been bought yet as college needs to paid for first then I can buy stuff for this.
Here's my parts/shopping list:
KMB jet drive combo 6 (has 500 can to 540 can adapter)
Vxl-6s esc, stock Spartan receiver tray, stock turn fins (asked the guy to hold this stuff for me and he's willing)
Aluminum dual water pickups that will act as trim tabs... (I know some will say that's dumb but i'll explain why soon)
Turnigy 3720 water cooled outrunner 1500kv motor (it's capable of handling 4s which is all i want to run, it's also watercooled)
Stock Traxxas waterproof receiver box
Traxxas 7600mAh 2s 25c lipo in series for 4s (I have one already and i want to keep cost down too but i will go for a higher c rating later)
Traxxas 2075 for steering (i already have that)

I think thats everything beside screws and bolts and cooling stuff....

I want to do this because i went to garner state park this summer and loved the rapids. I found the nqd jet drive boat on rc sparks youtube videos and i cant get over the jet boat. I live next to the gulf of mexico so there isnt any rapids but i still like the idea of a jet boat. I also plan to go to New Braunfels the last weekend in august to have some fun in the rapids so thats my goal to get this boat done by. I want to do a V hull boat for a jet drive because i've noticed cigar boats like the nqd and other jet boats like it jump out the water and i worry that could cause the motor to over rev and shatter the drive shaft or burn up the motor. The Spartan boat is gonna be the platform for now just cause i got the hull at a good price.

I also will be building a nqd tear into jet boat for my little brother. this boat will be less powerful. But this build probably wont happen till September which is when his b-day is so if i can do it quietly then maybe i can surprise him...
Let me know what ideas you have!

[ManDime]

So change of jet drive units. I found MickieB on here who sells jet drives and boats for them. I will be getting one of those soon for the build. I also found a motor similar to the 540xl that is originally paired with the vxl-6s for a good price so imma go that route. With the mickie jet drive, i will need a motor mount but that research will begin after i get the motor and jet drive so that i buy the right one.

[rearwheelin]

If you need some kind of motor mount I make custom ones, not sure if you can just buy one for your application .

[mickieb49]

Best of luck there Paul,
I found the kmb units fall apart, the rear stator does not fix into the rear cone properly and as such mind spat out the back and gone forever. Before that I aso had problems of cavitating / loading up the jet, You may have more luck there, that's if you are still going with the KMB unit.

[ManDime]

Best of luck there Paul,
I found the kmb units fall apart, the rear stator does not fix into the rear cone properly and as such mind spat out the back and gone forever. Before that I aso had problems of cavitating / loading up the jet, You may have more luck there, that's if you are still going with the KMB unit.

Thanks, rearwheelin, i'll probably take you up on the offer once i figure out the dimensions and everything. If you can make a mount where all 4 corners of the mount on the mount can be adjusted up and down, like a universal fit, then that'd be great and i wouldn't have to worry about its fit.

Didn't know about the kmb jet drive problems. Thanks for the heads up! I do like your design as it is actually an impellar where as the kmb is just a poorly designed and looks like a cut down propellar. Thanks for your advice one making a flot spot in the hull. I will be looking into the best way to do that and ill probably draw it up. Can i ask, what's the dimensions of the water inlet for your jet drive? (height, width, length) Thanks again!

[ManDime]

Ok so i figured i would use this motor mount as it can be trimmed a bit and its watercooled: http://www.offshoreelectrics.com/pro...prod=ose-80210

[ManDime]

Made so progress mapping out where i want to cut today:





this pic is what the cut will look like on the inside:



the cut is 8" long with a 2" width and has a 3" chamfer. I will be filling the hole with a metal plate to mount the jet drive that i will cut down... it may be heavy, it may not. I will weigh it and look at my other options. I may consider fiber glass but i've never messed with the stuff.

[mickieb49]

Width looks to be ok, looks like you may want to make the lead into the flat section a little longer, more like the same length as the flat section will be.
Dont be afraid of fiberglass, it can be very forgiving, use some alluminium as a mold like taped to the bottom, then lay the matting and resin on the inside, when it has cured ( overnight) pull the tape off and then pull the alloy off ( it should release reasonably easy) then you have a fiberglass ride pad and lead in.

[ManDime]

Alright so i figured that carbon fiber will actually look great so i found this: http://dragonplate.com/ecart/product...ID=3976&cID=94
It's 2mm thick which i think will be ok. It's a 6"x6" sheet and since the inlet of the jet is 40mm wide (almost 2 inches) i shoudlnt have a issue with fit. I will cut the sheet in two so that one half can be used for the chamfer section while the other will be used to mount the jet on. I plan to make the jet mounting section have some over-hang to protect the jet nozzle.
And i forgot to mention but i will be extending the chamfer by an inch to see what it looks like.

[ManDime]

Here's how the carbon fiber sizes up:



It's 1.5mm which will work great for boats but not good for cars. It will be jb welded onto there. I will do a 1/2" overhang on the rear. I'll make progress on cuts and what not when i have time tomorrow.

[ManDime]

Here's where i am at:





Little slow lately as money was needed elsewhere. Also got a castle 2400kv motor i will use for the boat as i got it for a trade. I also will be using a hobbywing 120a esc that i will order next check. But i have ordered the Mickie Beez jet drive though! Shan't be long now lol.

[ManDime]

Havent updated you guys in awhile but i have made progress and have installed the MickieB Jet drive. I'll make it short:





Test fit



Pre assemble:



Motor attached:



Getting ready to mount it:



More pics next post!

I think it looks sweet!!
Alright so setup or what is to be the setup:
Motor: Castle 2400kv
Esc: Mystery 200a
Batteries: two 4s Lipo in parallel
Motor mount: kintec racing 36mm
Cooling: standard Spartan cooling tubing and 36mm cooling jacket
Servo: undecided but budgeted at $40

I do plan to get some 3M carbon fiber wrap to clean up the rear and bottom of the boat. I still have to seal test the boat but i wont be doing that till i put on the carbon fiber wrap which should be in early next week. I still have to order motor mount, servo, servo mount, cooling, and 4s lipos.

[ManDime]

And, it's mounted!

[paDDY]

Nice!

[tunnelvision0323]

looks killer!!! im interested to see it run