JET-POWERED - Maverick Blackout V2
Discussion
Dear Professor!
Fantastic to hear from you and indeed on these boards! Good one for remembering the search terms!
Before I forget - can you PM me your mobile please!
Collective - myself and the Prof (Rob) met in the most macho of circumstances - Ante-Natal classes! Seven years ago now.
So - on to updating the Collective.
I've been quiet lately, but what's been happening is:
1) I haven't yet posted a static video, because that is of course all about the sound, and the really odd thing is that once it gets much past 40,000RPM, the microphone simply ceases to be able to interpret the noise AT ALL, whatsoever - and instead completely invents a noise very much like that of playing with an old-fashioned radio dial (high-pitch/low pitch affair) - it's literally nothing to do with the sound being output.
2) I've been sourcing and testing on rugby fields so far, for safe straight runs, with enough left over to come (steer) to a standstill. One of these I will certainly video - perhaps now with the Professor's help. I've simply been looking for someone worthy to be taking that first video! And I suspect that at a distance, the video's microphone should hopefully just pick things up as they are really sounding.
3) I've just written to Santa Pod - with a view to assessing top speed. The clincher is, it really needs to be followed in a car, to ensure no going out of transmitter range. The Prof's now got dibs on that job - and to boot it will therefore be in his (proper) Audi S8, no less!! 'Jet-powered scale car has top speed assessed using an Audi S8'! (Shhhh - it'll prob only get up to 80/90mph)
4) I'm also in talks with a few parties who do custom bodywork for left-of-field vehicles and motorbikes, with a view to creating bodywork to pick up on what someone here said - that it looks a bit like the Tumbler from behind! And feck me, it really does! One of these sources is connected with the Fast & Furious team, who use scale radio-controlled models (I think it was both third and fifth-scale) for the movies - however, I reckon I'm going to have more luck with the more sane resources on that one - have to go to Kent for that! If any of you have any contacts in that regard, please do say - I'm looking at maybe fibreglass or carbon fibre for the middle onwards - the back end might need metal.
5) I've just today picked up a small drum of Mobil DTE Oil Light - from fellow PH'er Norbert's (Dentressangle) Crick depot - to use instead of synthetic two-stroke (at 5%). This seems to be the recommended oil. I'm hoping Fugazi checks in here soon - as would like to know his thoughts on that - the thing being that two-stroke is designed to be burned (but (therefore?) has been leading to gummed bearings, even for me), but DTE is not - so I'm planning on using it at a lower percentage (3%). The entire point of adding oil, is to lubricate the bearings - so one that does not burn off seems to have a logic behind it.
So - next post will hopefully be a video!!
Fantastic to hear from you and indeed on these boards! Good one for remembering the search terms!
Before I forget - can you PM me your mobile please!
Collective - myself and the Prof (Rob) met in the most macho of circumstances - Ante-Natal classes! Seven years ago now.
So - on to updating the Collective.
I've been quiet lately, but what's been happening is:
1) I haven't yet posted a static video, because that is of course all about the sound, and the really odd thing is that once it gets much past 40,000RPM, the microphone simply ceases to be able to interpret the noise AT ALL, whatsoever - and instead completely invents a noise very much like that of playing with an old-fashioned radio dial (high-pitch/low pitch affair) - it's literally nothing to do with the sound being output.
2) I've been sourcing and testing on rugby fields so far, for safe straight runs, with enough left over to come (steer) to a standstill. One of these I will certainly video - perhaps now with the Professor's help. I've simply been looking for someone worthy to be taking that first video! And I suspect that at a distance, the video's microphone should hopefully just pick things up as they are really sounding.
3) I've just written to Santa Pod - with a view to assessing top speed. The clincher is, it really needs to be followed in a car, to ensure no going out of transmitter range. The Prof's now got dibs on that job - and to boot it will therefore be in his (proper) Audi S8, no less!! 'Jet-powered scale car has top speed assessed using an Audi S8'! (Shhhh - it'll prob only get up to 80/90mph)
4) I'm also in talks with a few parties who do custom bodywork for left-of-field vehicles and motorbikes, with a view to creating bodywork to pick up on what someone here said - that it looks a bit like the Tumbler from behind! And feck me, it really does! One of these sources is connected with the Fast & Furious team, who use scale radio-controlled models (I think it was both third and fifth-scale) for the movies - however, I reckon I'm going to have more luck with the more sane resources on that one - have to go to Kent for that! If any of you have any contacts in that regard, please do say - I'm looking at maybe fibreglass or carbon fibre for the middle onwards - the back end might need metal.
5) I've just today picked up a small drum of Mobil DTE Oil Light - from fellow PH'er Norbert's (Dentressangle) Crick depot - to use instead of synthetic two-stroke (at 5%). This seems to be the recommended oil. I'm hoping Fugazi checks in here soon - as would like to know his thoughts on that - the thing being that two-stroke is designed to be burned (but (therefore?) has been leading to gummed bearings, even for me), but DTE is not - so I'm planning on using it at a lower percentage (3%). The entire point of adding oil, is to lubricate the bearings - so one that does not burn off seems to have a logic behind it.
So - next post will hopefully be a video!!
Silver Smudger said:
This needs to happen!
Don't worry, I won't let the idea go without execution! Interestingly, the Tumbler was based partially on a chimeric hybrid of a Lamborghini Aventador & a Hummer - however I feel it's landed with a visage which looks much more like the Predator (alien)! The Tumbler to my eyes positively has 'mandibles'! UPDATE!
Okay - so I'd been engineless for about three months, waiting for the newer version of the engine to arrive.
So this now has the Wren DCi100 - same thing externally, largely - but now much is fully internalised - such as pump valves and main brains of the ECU. Also - the starter motor and fuel pump are now brushless, making for much more accurate fuel-control, and overall RPM control as a result, as well as faster spool-up.
PICS
While the carcass was sitting there devoid of an engine, I decided that I needed a bigger fuel tank - hence what you see now, versus how it looked on Page 1 of this thread.
VIDEO
https://www.youtube.com/watch?v=bBtSnW5_fHo&fe...
Okay - so I'd been engineless for about three months, waiting for the newer version of the engine to arrive.
So this now has the Wren DCi100 - same thing externally, largely - but now much is fully internalised - such as pump valves and main brains of the ECU. Also - the starter motor and fuel pump are now brushless, making for much more accurate fuel-control, and overall RPM control as a result, as well as faster spool-up.
PICS
While the carcass was sitting there devoid of an engine, I decided that I needed a bigger fuel tank - hence what you see now, versus how it looked on Page 1 of this thread.
VIDEO
https://www.youtube.com/watch?v=bBtSnW5_fHo&fe...
Fugazi buddy!
Glad to have elicited comment from you on this, sir!
The video's a bit naff, plus I was one-handed at the time, hence some awkward re-positioning of the camera, at points! Really - my next video will be of it actually moving, too.
The engine's super-lovely!! It starts in about 30 to 45 seconds - and seems almost to 'skip' steps I was used before to witnessing - e.g. rise-to-temp while you hear the flames swirling inside, leading to Switchover once it reached the designated temp (200degrees) - this one switches over and starts ramping even as low as 50degrees - I simply can't see the delineation - it just starts almost in one very quick sequence - I'm looking for Switchover - and it's idling already!!
Also - the newest consensus seemed to be that Mobil DTE Oil Light was positively rubbish for the bearings (my previous one had started to whine quite early), such that Wren are now saying that if you use it, dose it also with two-stroke or something!
The elixir of high-temp bearing oils though seems to be Aeroshell 560 (quite new) - and it's made a world of a difference! Two-stroke would gum the bearings - whereas on this stuff, they keep spinning for a good while, after starter disengagement on cool-down.
It's supposed to output a tad more than 100Newtons - but that's unofficial - the official output is still the 100N.
Very happy overall - and believe or not - thanks to and for all the support from those 'jet-nuts' like yourself, and Ben (who's also got a thread here for his two jet cars) - it's made it worth it to get past all the aggro of setting these things up, and getting it all just so!
Glad to have elicited comment from you on this, sir!
The video's a bit naff, plus I was one-handed at the time, hence some awkward re-positioning of the camera, at points! Really - my next video will be of it actually moving, too.
The engine's super-lovely!! It starts in about 30 to 45 seconds - and seems almost to 'skip' steps I was used before to witnessing - e.g. rise-to-temp while you hear the flames swirling inside, leading to Switchover once it reached the designated temp (200degrees) - this one switches over and starts ramping even as low as 50degrees - I simply can't see the delineation - it just starts almost in one very quick sequence - I'm looking for Switchover - and it's idling already!!
Also - the newest consensus seemed to be that Mobil DTE Oil Light was positively rubbish for the bearings (my previous one had started to whine quite early), such that Wren are now saying that if you use it, dose it also with two-stroke or something!
The elixir of high-temp bearing oils though seems to be Aeroshell 560 (quite new) - and it's made a world of a difference! Two-stroke would gum the bearings - whereas on this stuff, they keep spinning for a good while, after starter disengagement on cool-down.
It's supposed to output a tad more than 100Newtons - but that's unofficial - the official output is still the 100N.
Very happy overall - and believe or not - thanks to and for all the support from those 'jet-nuts' like yourself, and Ben (who's also got a thread here for his two jet cars) - it's made it worth it to get past all the aggro of setting these things up, and getting it all just so!
Fugazi said:
Not had chance to look at the video yet, but I love the smell of burning B&Q's Paraffin in a morning... 
Indeed!! I'd been without an engine for three months, and was seriously missing that smell of 'aviation' - literally the same smell as that of airfields. So now I go and bathe in it, much to the Mrs' chagrin!!In this weather, it's especially nice too. Garage-based heater - which actually ends up defrosting the entire car, if I'm playing with it for long enough (car parked on drive, facing garage opening).
Finally - a video of motion of some sort!
The microphone ceases to pick up the actual noise at certain RPMs, sounding more like trying to tune a radio.
On move-off, watch the tree-foliage in the further background. That was about 100,000rpm. The 'crash' into foliage was deliberate, to catch it safely as I concentrated on video and throttle. Oh - and it could easily have ploughed that stuff down and gone over it - but at much beyond 60,000 RPM, it's too loud to be that close to, without ear defenders. At full throttle, you can hear it a mile off, literally.
https://youtu.be/IguVcGxH15A
And another...I just blipped the throttle to about 70% power for a few seconds, the rest was momentum:
https://youtu.be/uCFKifDL-2U
And lastly - gentle movement!
https://youtu.be/nZ-0m8pty2k
Edited by Arif110 on Monday 18th May 01:18
Edited by Arif110 on Monday 18th May 01:29
Ha ha!! Thanks buddy!
The tank'll take 4.2litres (normal paraffin mixed with Aeroshell turbine oil at 5%) - and I get through it in about 40mins, or a fair bit less if full-throttling it a lot.
It idles at 45,000 RPM, full-throttle's 160,000RPM, and I've clocked it at 90mph on smooth tarmac (needed a 500m stretch) - however, I'm normally on grass.
If tootling along at a bit more than walking-pace, it has a range of just under 3miles.
I've never had so much fun - full stop, ever. The sound and the smell!
Arif
The tank'll take 4.2litres (normal paraffin mixed with Aeroshell turbine oil at 5%) - and I get through it in about 40mins, or a fair bit less if full-throttling it a lot.
It idles at 45,000 RPM, full-throttle's 160,000RPM, and I've clocked it at 90mph on smooth tarmac (needed a 500m stretch) - however, I'm normally on grass.
If tootling along at a bit more than walking-pace, it has a range of just under 3miles.
I've never had so much fun - full stop, ever. The sound and the smell!
Arif
ecsrobin said:
That is superb, now I want a small jet engine don't know what for but I want one.
That was precisely my situation to begin with! I initially thought I'd just be getting it to sling on a workbench, and that would be that - I'd happily spend hours tinkering and running it.But then the alternative project occurred to me, and thankfully the rest is history.
I've been into jet engines ever since I was a kid (am 41 now) - so feel very blessed to be living in the day and age when model turbines came into the reach of amateur enthusiasts.
I also went personally to Wren in Barnsley to get the engine, and I pop back there randomly to keep in touch - that is also a big part of the ownership experience for me, as Wren were a large part of pioneering the technology.
Arif
rhinochopig said:
Needs to mounted to a bicycle though. How have you resisted doing so???
An excellent question!! I literally wake up having dreamt about how that would be executed! The thing is that it wouldn't be road-legal, so would need to be discrete, so as not to draw the wrong sort of attention even when off - so panniers for twin fuel tanks, and really all that would give away that there's anything odd about the bike would be a little hole at the back. The bulk of the sound actually exits at 45 degrees to the nozzle (rather than if you were directly behind) - so I'd need to develop deflectors of some sort, or rather, it would be situated slightly down a metal tunnel.Also - that engine on a pushbike I think would only take a person to about 30mph on the flat, whereas I'd want it to be a bit more notable than that, seeing as one can do 30mph anyway on a road-focused bike. So we're looking at a 20kg thrust engine, I'd only ever source it from Wren, and they don't yet make that version of their engine in the newer 'digitised' version.
So when they do...!
Arif
I seem to recall some TV programme, possibly even Top Gear, putting the issue to bed for good, through getting a VOSA bod or somesuch to examine and comment on a jet-powered bicycle. I think the problem is that it is a 'self-propelled vehicle' - and as such becomes subject to all the other reg's that the likes of quad bikes have to comply with - lighting, etc.
However - in reality, it would seem to be treated as a grey area - much in the way of A-frames being used to tow cars (unbraked).
I'd only ever go on lonely country lanes at quiet times!
Apparently there's a fireman that Wren know of, who regularly travels to work on one!
Fugazi buddy - I used to be extremely molly-coddling over the engine and debris - e.g. making bespoke secondary FODs with zinc car bodywork repair mesh - but these seemed to trap more things too, and were a pain to hoover out after every run.
So now I just leave it with its own FOD screen, and really what it does it attract grass and other 'long' things to itself, such that a fast blat means its created its own secondary filter! After it turns off, it all largely falls away, then a bit of hoovering!
However - in reality, it would seem to be treated as a grey area - much in the way of A-frames being used to tow cars (unbraked).
I'd only ever go on lonely country lanes at quiet times!
Apparently there's a fireman that Wren know of, who regularly travels to work on one!
Fugazi buddy - I used to be extremely molly-coddling over the engine and debris - e.g. making bespoke secondary FODs with zinc car bodywork repair mesh - but these seemed to trap more things too, and were a pain to hoover out after every run.
So now I just leave it with its own FOD screen, and really what it does it attract grass and other 'long' things to itself, such that a fast blat means its created its own secondary filter! After it turns off, it all largely falls away, then a bit of hoovering!
Fugazi buddy,
1) Sometimes after a run, I've taken to spinning the engine up manually to listen to the bearings, using a vac!
It will also obviously suck any accessible debris out - but could it do any harm, that you can think of?
And if powerful enough, could it suck debris out from the front end too, even though the path is not of course direct, but centrifugal?
2) Fuel cavitation - I was using a 'brass-balls' fuel filter dongle in the tank itself (as well as the aluminium can-type on the pressure-side of the fuel pump) - only to realise that the engine at times wasn't revving beyond 100,000 RPM, and indeed would flame out with bubbles in the fuel line coming from the tank - as though it was empty, but when it was nearly full!
So - I'd created cavitation, hadn't I? The sheer force of suction pulling the fuel apart in effect, and releasing stored air?
I've binned that dongle now, and allowing the main fuel filter to do its job. I'd been trying to 'protect' the fuel pump!
Arif
1) Sometimes after a run, I've taken to spinning the engine up manually to listen to the bearings, using a vac!
It will also obviously suck any accessible debris out - but could it do any harm, that you can think of?
And if powerful enough, could it suck debris out from the front end too, even though the path is not of course direct, but centrifugal?
2) Fuel cavitation - I was using a 'brass-balls' fuel filter dongle in the tank itself (as well as the aluminium can-type on the pressure-side of the fuel pump) - only to realise that the engine at times wasn't revving beyond 100,000 RPM, and indeed would flame out with bubbles in the fuel line coming from the tank - as though it was empty, but when it was nearly full!
So - I'd created cavitation, hadn't I? The sheer force of suction pulling the fuel apart in effect, and releasing stored air?
I've binned that dongle now, and allowing the main fuel filter to do its job. I'd been trying to 'protect' the fuel pump!
Arif
Video - not quite one of fast motion, but my solution to getting across visualising its thrust!
https://youtu.be/Swl5m_PGgSI
https://youtu.be/Swl5m_PGgSI
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