Petrol to Paraffin - Jet-powered Maverick Blackout !

[Arif]

Hi Collective!!

 

[Note - I have since this post, now added pics - thanks Tamiya dude! I hope they're not too big, I did opt for Autosizing down to 800px]

 

Having been the continuously proud owner of a Maverick Blackout V2 with the requisite servo upgrades and a Zenoah GC290 4-bolt - I thought I'd out-do even that power unit...

 

So the thing is now sporting a Wren iKero 100 jet turbine - (10kg thrust). It idles at 50,000 RPM, and spins happily up to 160,000 RPM.

 

I was stressing about how botched the fit was going to look, but it almost looks as though designed out of the factory with it in!  Everything else is still in-situ - apart only from the exhaust muffler from the Zenoah.  I'm figuring that I'd like the added momentum for now, over the losses in terms of inertia.

 

The curve of the engine fits perfectly atop the suspension-plate - then nestled laterally by the two posts which normally held the bodywork up/on. It's screwed-down using it's own engine strap - screwed into the top of the two posts (obviously cut).

 

The back of it is simply then sitting on the roll-cage frame member - perfectly positioned for this role. It's not sitting directly on the beam, as the beam os lower than the suspension member, making for the engine pointing upwards - so the perfect spacer has proven to be the rubber strip that comes with a new petrol tank. I've laser-thermometered the whole set-up, and nothing should be heat-stressed - and esp not for the relatively short runs one would do.

 

I haven't been able to run it out in a field yet - but in garage tests it managed to shove forwards two six-packs of 1.5litre Evian bottles, on very rough grippy floor, too.  That wasn't of course the objective at the time, but is what happened.

 

I've managed to get it to talk to the Spektrum (DX3, iirc) transmitter, thankfully.

 

Thanks for all of your help and support over the years - esp Hebby & Nitroholic - it's kept me interested in the whole game, and has led me to what must clearly be a major watershed in my RC vehicle ownership experience!

 

P.s. And none of this propane/separate source of blown-air cr@p to get it started - you can just walk up to the vehicle, switch on the receiver on it, pull the trigger - and it commences all procedures!

 

 

Arif

Edited July 3, 2014 by Arif

[mini-z-awd]

any pics as my mate was going to do this to a baja 5b 

[Arif]

Yup - waiting for someone like Hebby or Nitro to help me with posting them - I'll have to e-mail them across.

[Nitroholic]

Forget pics....we want video

 

Sounds like a fun project. Definitely need to have the tail of hte motor pointing up a few degrees....as that keeps the front end down and prevents it trying to be an aircraft! Going to be pretty much straight lines only though.... as the thrust will fight the steering input.

 

Might be worth investing in one of the new stability control systems.

[Tamiyacowboy]

first off congrats on the turbine mod. 

 

is this powered from pure thrust alone or is there a link running from the turbines main shaft to the gearbox ?

i see jet trucks, and turbine powered catamarans.

 

as for uploading pictures: 

 

Imgur, grab yourself an account here for free : http://imgur.com/

 

now log into imgur, and on the right side where it says computer

just below is a tab that says AUTOSIZE , click this and choose the size you wish pictures to be ( 800 is a good choice )

next click the computer tab and browse to your images you wish to upload. 

(hold down the shift key to click and highlight multi images if need /wish) 

click ok and it starts uploading. 

 

now click on an image thats been uploaded.

an new little window will open, on the right panel

will be the line DIRECT LINK , beside the wording direct link

you will find an address right click it and select copy. 

 

IN MSUK forum in the message box you type in click the picture like box on the top row

you will see a smile face and a my media tab ( just below these is the image/picture tab)

click this and in the popup window right click and select paste.

now click ok/done and your picture will be added to your message.in the topic/thread

[Arif]

Okay - brilliant dudes - I'll sort my Luddite act out and sort posting pics today some time.

 

Nitro buddy - excellent thoughts about steering and angle of thrust. I instinctively let it dip ever so slightly up (imperceptible, pretty much) - but got it right at when it's jammed against the aforementioned Evian bottle-stack, as it put out more thrust, it dived further into the front suspension, tilted forwards and down - job done!

 

Steering - okay, so now I have my justification for keeping the weight of the old running-gear and Zenoah on-board! There's a second Blackout fuel tank sitting on the front as well - for the paraffin. The old tank, everything is all in place as before.

 

Video!! Yup - once I've got used to handling it, for sure sir.

 

Tamiya dude - thanks for the Dummy's Guide - will follow that &/or some of help Nitro's already given by PM.  Good question - it's thrust alone. The geared stuff is orientated towards helicopters, and I just wasn't confident going that route.

 

Apparently an object will 'use up' 5% of available thrust, expressed as mass (weight) - so with 10kg of thrust, there's the bulk of it left to actually propel the vehicle.

 

I'm used to needing decent grass to go on for traction - but by definition now, for the straight line at least, traction is not the issue! I'll stick to grass to see what it can do. It must be pretty decent, as it's the same engine which can propel a person on a bike to 30+mph. (Don't worry, I won't!)

[Tamiyacowboy]

there is only one place you can really run a machine like this at .......... 

 

Santapod after a days drag racing when theres a lot of sticky rubber been layed down,

160,000rpm will come right at the end sweet spot so i would say more like 120k rpm

giving a small discount for weight to thrust / drag coeffiency .

 

at full beans you do risk a bellypan up i would be laying down some lead in that front end and scooping the airflow

to some dynamic flow help hold it down. if it goes belly up its gonna be able to lift its own weight with thrust .

so a safety shutdown toggle switch added and linked to a third chanel.

 

you must run this on the hard stuff, get some large scale onroad race slicks, a super long quarter mile drag strip and open the beans up

[Arif]

Tamiya dude - indeed - I've gotta shift my thinking of it as a mud-plugging off-roader maybe. For now the grass will create a soft/forgiving performance margin within which to get to know it.

 

You seem to know your turbines? What's your history sir!?

 

(Also, I note you're a Canon man and quadcopter user? I nearly went for the DJI Phantom Vision 2 - but with all the flyaway issues I'm hearing about, I thought my money would be better spent on something that stays on the ground - hence my trip to Rotheram to pick up a Wren from Wren themselves!)

[Arif]

Actually Tamiya dude - on that note, what kind of speed do you think that 10kgs of thrust will get the Maverick to - even on grass?  I'm of course used to the Zenoah taking it to at least 30 (40?) mph; but assuming it stays on the ground - what top speed might you anticipate for it, both on grass, and then on slicks on tarmac?

 

Arif

[jordanp]

wow dude i can post the pics for you if you want

this sounds so awesome cant wait till the video

[Arif]

As for a video - given all the extremely irritiatingly-taken videos out there on YouTube, it's going to be a question of finding someone who isn't a numpty with the camera - you know, pointed at the grass or their crotch half the time. I wish I were Hebby - who does amazing vids and the edits to boot!

[Tamiyacowboy]

Loose that big engine !!!!! 

 

your weight is comming from that large engine mounted midsection. loose that 5Lb dead weight is

a more better power to thrust ratio.

 

Speed wise, well its the lap gods here, speed is governed by many factors and the largest is WEIGHT,

less weight = more thrust and more efficent trust use, its not being wasted trying to push you through stick grass.

speed will be ball park. 20-30mph as a round ish number, 
but one cannot say for certain how fast a machine will be, you can have a very good mathimatical outcome stating x+y+z/ drag-thrust-weight = a couple billion mph

but in reality its more like 40mph. 

 

your main problem is bulk, weight and stance.

 

the truck is big and wide, so its gonna have alot of drag inefficency , no smooth flow of air.

weight, carrying an extra engine onboard without it coupled into the drive system, hybrid use, would be running on gas via a two/three speed box.

when engine and machine hits a certain rpm, the gas engine shuts down and the turbine takes over, this way you can start the trubine while running to force air into the

combustion chamber and have that turbine spinning over, it just takes over from the engine at the right time and gives that final boost. 

 

stance. being wide she commands alotta drag, its big and bulky and this will have effect on top speed.

a slimmer body and chassis with a more piercing style shape will be better.

 

the wren is a very sweet turbine, and in my eyes is somewhat spoilt by the large chassis its stuck to.

think Jet truck rear mounted bed on a flat wise chassis, the old king hauler style flow cab ( not a big square box like todays flat front cabs ).

now a step up would be a bajab5 style chassis but stretched long around 2ft + long.

large rear tyres and some thin spoked rims upfront on a thin long chassis.

Add a long thin drag styled body, a single chute release to a 3 chute drag brake, fuel tank sat front wards to keep weight

good and something for thrust to work on ( steering wise, dont want that getting light at say 50+mph) 

 

Now a turbine drag racer  model wise 100mph is doable , just one problem you need over a mile to wind this up fully on the beans

and you will need a return trip fueling station to gain any records (am sure you have to do two runs there and back the average of two is you top speed).

 

 

yep canon owner, quad pilot and just a good few years in the hobby. 

[Nitroholic]

Personally....I'd leave the 2 stroke motor there....and use the jet thrust as a boost. The petrol motor will be good for getting it shifting, as that's where a thrust based system really sucks. Then....you crank up the turbine....

 

The throttle control will pose issues.....as you want to kill the petrol motor so the clutch disengages and the turbine takes over. Kind of like a helicopter with the throttle hold/idle up deal. Drop the petrol motor back to idle and ramp up the jet

 

I'd also think about some sort of Outerwear type shroud for the jet intake....the mesh looks a little course.

 

Thanks to the Blackout base, it's alsways going to be as aerodynamic as a brick... but with enough force applied...bricks fly

[jordanp]

cool guys

[lel-95]

saw this posted on pistonheads, took me a few moments to realise it was a bit more than a standard 2 stroke! 

 

 

looks like a beast! 

[Tamiyacowboy]

you cannot shroud the turbine intakes only to scoop air into them.

using an outdrive cover will block it and make less thrust.

only needs a tiny thread to get drawn in and that engine gives up.

 

best way is protect it from dirt ingestion and that is running on the good old blackstuff. 

 

but to be honest i would rather see the wren in a lovely scale jet single mig fighter maybe even a lightning II 

or if not coupled into a cnc jetdrive and a deep V hull - or a straight prop jetdrag boat

[Arif]

Slight technical update - it kept on stalling (flaming out) under hard acceleration - there's me stressing that the most reliable engine about is not being reliable for me - turns out that the fuel was chucking to the back of the tank, leading then of course to bubbles in line & flame-out. And at full tilt, it'll get through the whole tank in a few minutes or under, so it will almost always have space to let the remaining fuel gather to, away from the pick-up. The same will then happen on steering. Now I see why a lot of other models have tall tanks! Evian bottles will have to serve as a stop-gap.

 

Does anyone here know of the right solution?  I've heard that the jet models crew use something call plasma bags?  Other apparently improvise by using drip-bags ffor hospital IV??!!

 

I'm thinking that the quickest solution for now is going to be a tall tank.

 

I guess it was never a problem for the Zenoah as it didn't suck fuel all that fast.

[(-:AD:-)]

a tank with baffles in it? if they do one for this size or if you could make one.

 

something similar to this

[just rolling]

......bloody hell.......like summit outta mad Max :-)

[Nitroholic]

You could always use an aircraft tank, with the fuel pickup at the back ...

[Arif]

Hi all!

 

I found another forum I frequent much more active in this particular regard - and so the full write-up and updates are here:

 

http://www.pistonheads.com/gassing/topic.asp?h=0&f=159&t=1422812&mid=0&i=0&nmt=JET-POWERED+-+Maverick+Blackout+V2&mid=0

 

There's even an expert on model jet engines on there!

 

Anyhoo - you'll see the fuel-tank solution I arrived at, in the end. Works fantastically, and I even get to use quite a way towards the tank being empty.

 

I'm going to get bodywork custom-made for it, to get it to look a bit like the Tumbler (Batman Begins)

Edited August 10, 2014 by Arif

[atom3624]

https://www.youtube.com/watch?v=W4whKFUgc_0&feature=youtu.be

 

Video.

 

Al.

[atom3624]

I like the development model: 

 

Al.

[Arif]

Bump...for those interested in 2016!

[norcoforever]

I would like to add that this is incredible to see and hear go!