Pointless noisy and...
 

  You don't need to be an 'investor' to invest in Singletrack: 6 days left: 95% of target - Find out more

[Closed] Pointless noisy and polluting II

87 Posts
58 Users
0 Reactions
465 Views
Posts: 2642
Free Member
Topic starter
 

Instead of riding my bike, I've been fiddling in my shed...

...and made a jet engine

[url= https://www.misterg.org.uk/photo/images/2021/11/25/IMG_8797.md.jp g" target="_blank">https://www.misterg.org.uk/photo/images/2021/11/25/IMG_8797.md.jp g"/> [/img][/url]

[url= https://www.misterg.org.uk/photo/images/2021/12/03/IMG_8886.md.jp g" target="_blank">https://www.misterg.org.uk/photo/images/2021/12/03/IMG_8886.md.jp g"/> [/img][/url]

[url= https://www.misterg.org.uk/photo/images/2021/12/03/IMG_8916.md.jp g" target="_blank">https://www.misterg.org.uk/photo/images/2021/12/03/IMG_8916.md.jp g"/> [/img][/url]

[url= https://www.misterg.org.uk/photo/images/2021/12/03/IMG_8919.md.jp g" target="_blank">https://www.misterg.org.uk/photo/images/2021/12/03/IMG_8919.md.jp g"/> [/img][/url]

It even works!

https://youtu.be/K1eyy7V9sas

 
Posted : 03/12/2021 12:56 pm
Posts: 13601
Free Member
 

Impressive! Is that a kit?

 
Posted : 03/12/2021 1:01 pm
Posts: 919
Free Member
 

Brilliant, now go back in the shed and attach it to your bike - this is a bike forum after all 🙂

 
Posted : 03/12/2021 1:02 pm
Posts: 8527
Free Member
 

Fantastic! awesome noise.

I used to test Aircraft engines, you just transported me back to standing out next to one running at 25% power on a nightshift, in january 🙂

 
Posted : 03/12/2021 1:04 pm
Posts: 4313
Full Member
 

Very cool!

 
Posted : 03/12/2021 1:06 pm
Posts: 11381
Free Member
 

The cat had the right idea

 
Posted : 03/12/2021 1:07 pm
Posts: 8318
Full Member
 

Sometimes just because you can does mean you should 🙂

 
Posted : 03/12/2021 1:09 pm
Posts: 9135
Full Member
 

Cool and amazing.

 
Posted : 03/12/2021 1:12 pm
Posts: 44146
Full Member
 

YOu forgot dangerous in your list of attributes!  Love it

 
Posted : 03/12/2021 1:13 pm
Posts: 1467
Full Member
 

Can you make a pulse jet next please?

 
Posted : 03/12/2021 1:23 pm
Posts: 45504
Free Member
 

Top work.

 
Posted : 03/12/2021 1:26 pm
Posts: 9539
Free Member
 

Absolutely awesome.

 
Posted : 03/12/2021 1:28 pm
Posts: 2642
Free Member
Topic starter
 

Brilliant, now go back in the shed and attach it to your bike

😀

The though had crossed my mind - I need to get it running on kerosene first as there isn't enough energy in propane to get it up to full power. (It'll also be very under-powered compared to modern commercial ones, but that's a limitation of a home made turbine wheel, rather than one cast from Inconel.)

Thanks - it's not a kit - it's an old design from the book by Thomas Kamps.

[url= https://www.misterg.org.uk/photo/images/2021/10/26/Turbine-v92.md.pn g" target="_blank">https://www.misterg.org.uk/photo/images/2021/10/26/Turbine-v92.md.pn g"/> [/img][/url]

Everything was made in my shed (on my Chinese mini-lathe), except the compressor wheel which is a spare part for an Audi 100 turbocharger. 🙂 (There's some build photos on the MIG welding forum if anyone is interested!)

 
Posted : 03/12/2021 1:35 pm
Posts: 12072
Full Member
 

That's great!

 
Posted : 03/12/2021 1:40 pm
Posts: 6513
Full Member
 

Colin Furze watch out!

Nice rightup on the mig forum

 
Posted : 03/12/2021 1:52 pm
Posts: 1886
Free Member
 

Nice work, enjoyed reading your thread.

 
Posted : 03/12/2021 2:18 pm
Posts: 2076
Full Member
 

Made from plans! That is a serious achievement for any model maker. I like that a lot :o) Thx for posting.

 
Posted : 03/12/2021 2:24 pm
Posts: 918
Free Member
 

Good Lord!
Although yours has been knitted by you, so is inherently better!

If I put one of these on a bike does it become an e-bike? Asking for a friend...

 
Posted : 03/12/2021 2:38 pm
Posts: 1332
Full Member
 

That’s lovely work. Chapeau.

 
Posted : 03/12/2021 2:49 pm
Posts: 91000
Free Member
 

When you get it going on kerosene let us know how much thrust it generates.

 
Posted : 03/12/2021 2:59 pm
Posts: 2880
Full Member
 

If I put one of these on a bike does it become an e-bike? Asking for a friend…

Putting one jet engine on a bike would be a terrible idea.

You'd be all out of balance and wobble all over the shop. No, you'd definitely need a pair of them to balance out the power!

 
Posted : 03/12/2021 2:59 pm
Posts: 10761
Full Member
 

Lovely stuff. Got plans for an afterburner?

 
Posted : 03/12/2021 3:04 pm
Posts: 918
Free Member
 

You’d be all out of balance and wobble all over the shop

A bit like no engines then...

 
Posted : 03/12/2021 3:04 pm
Posts: 519
Free Member
 

You, Sir, are a genius. That is awesome. One question; has the cat come back yet?

 
Posted : 03/12/2021 3:07 pm
Posts: 17728
Full Member
 

Great!!

What's the plan? Flying Black & Decker workmate?!

 
Posted : 03/12/2021 3:17 pm
Posts: 2642
Free Member
Topic starter
 

has the cat come back yet?

Ha ha - yes, he's home. He was just visiting his other residence.

@creakingdoor - you've obviously seen me ride! 🙂

When you get it going on kerosene let us know how much thrust it generates

That's the plan - if it generates something meaningful, then I have eyes on the panier rack on my fat bike. (Afterburner optional!)

Thank you all! 😀

 
Posted : 03/12/2021 3:18 pm
Posts: 507
Full Member
 

Amazing! It’ll look better at night. (Please) 🤞

 
Posted : 03/12/2021 3:31 pm
 db
Posts: 1922
Free Member
 

Fantastic!

Build a wind turbine next to offset the CO2 emissions 😉

 
Posted : 03/12/2021 3:59 pm
 Sui
Posts: 3107
Free Member
 

that is cool!

I need to get it running on kerosene first as there isn’t enough energy in propane to get it up to full power.

nah, Propane is very energy Dense just like LNG, (Hydrogen is awesome) the probelm will be with the liquid density of the fuel. You'll need to wind it up on Porpane before having Kero injected and atomising - can you do that with you're build, otherwise you'll need an electric motor to get it spinning and the injectors doing their bit.

what would work quite well is some Russian TS1 grade, it's more volatile than JET A1 kero so easier to start - do you want some 🙂 - often find people mixing petrol and Kero for this purpose (not advised though)

 
Posted : 03/12/2021 4:01 pm
 nuke
Posts: 5763
Full Member
 

Seriously impressive (Just been on the linked welding thread and trawled through the history of the build)....well done!

 
Posted : 03/12/2021 4:08 pm
Posts: 651
Full Member
 

Wow

 
Posted : 03/12/2021 4:09 pm
Posts: 2642
Free Member
Topic starter
 

Thanks

You’ll need to wind it up on Porpane before having Kero injected and atomising – can you do that with you’re build,

Yes (sort of) - it’s got vaporiser tubes for the kerosene, rather than atomising nozzles (it’s the way that all these “toy” turbines work). There’s a separate injector for propane to pre-heat the vaporisers for starting. Spool-up will be by driving the compressor wheel with a jet of compressed air (as in the video).

Luckily we have a tank with several hundred litres of kerosene in outside the house.

Thrust will be low by commercial standards, as the home made compressor wheel is limited to ~95k RPM.

🙂

 
Posted : 03/12/2021 4:22 pm
Posts: 9136
Full Member
 

Outstanding! Fascinated by that from start to finish. 🙂

 
Posted : 03/12/2021 4:26 pm
Posts: 13356
Free Member
 

Who do you think you are, Frank Whittle?
Seriously, that’s awesome!

A mate of mine was a toolmaker at Durham Science labs & made things for students who were from the likes of Rolls Royce. He made some proper impressive stuff.

 
Posted : 03/12/2021 4:35 pm
 Sui
Posts: 3107
Free Member
 

ahh don't use heating Kero, you'll coke it all up - are you North?

 
Posted : 03/12/2021 4:39 pm
Posts: 65918
Full Member
 

 
Posted : 03/12/2021 4:39 pm
Posts: 0
Free Member
 

How did you make the outer case and stand? I wish I could make things out of metal. Or out of anything that is that good.

 
Posted : 03/12/2021 4:57 pm
Posts: 11605
Free Member
 

Wait, you built a spot welder AS WELL?!?

Well impressed.

 
Posted : 03/12/2021 5:15 pm
Posts: 0
Free Member
 

That is fully awesome. Can I order one for my kayak?

 
Posted : 03/12/2021 5:20 pm
Posts: 4588
Free Member
 

Aren't you at risk of losing your hand or arm when you wave it around in front of the intake when you fiddle with the oil tank?

 
Posted : 03/12/2021 5:20 pm
Posts: 5890
Full Member
 

If it scares off cats I'll take two.

 
Posted : 03/12/2021 5:54 pm
Posts: 1725
Free Member
 

That is awesome.

Loved the build thread on the mig welding forum, especially for the ingenuity of how you built things with what tools you have or could rig up.

 
Posted : 03/12/2021 6:12 pm
Posts: 2642
Free Member
Topic starter
 

Thank you!

How did you make the outer case and stand?

The outer case is a sheet of 0.5mm stainless steel bent into a tube with an end cap of the same material spun over a plywood former.

The stand is welded up from some aluminium sheet, ground to be pretty & then anodised.

[url= https://www.misterg.org.uk/photo/images/2021/11/19/IMG_8567.md.jp g" target="_blank">https://www.misterg.org.uk/photo/images/2021/11/19/IMG_8567.md.jp g"/> [/img][/url]

[url= https://www.misterg.org.uk/photo/images/2021/11/23/IMG_8720.md.jp g" target="_blank">https://www.misterg.org.uk/photo/images/2021/11/23/IMG_8720.md.jp g"/> [/img][/url]

[url= https://www.misterg.org.uk/photo/images/2021/11/23/IMG_8721.md.jp g" target="_blank">https://www.misterg.org.uk/photo/images/2021/11/23/IMG_8721.md.jp g"/> [/img][/url]

[url= https://www.misterg.org.uk/photo/images/2021/11/23/IMG_8731.md.jp g" target="_blank">https://www.misterg.org.uk/photo/images/2021/11/23/IMG_8731.md.jp g"/> [/img][/url]

It's easy to come out with statements like the above, and give the impression that the outcome was assured. However, the truth is that I had no idea whether / if the result would be OK, but I'm chuffed to hell that it came out how it did.

If you want to make stuff, then start making stuff. You will learn.

 
Posted : 04/12/2021 1:04 am
Posts: 16216
Full Member
 

You are way to talented for my liking op!

Superb stuff mate.👍

 
Posted : 04/12/2021 1:07 am
Posts: 8904
Free Member
 

Wow.
.
.
Nothing further to add

 
Posted : 04/12/2021 2:31 am
Posts: 3284
Free Member
 

I don't know what the fuss is all about, it's not exactly rocket science is it Dr Von Braun?

 
Posted : 04/12/2021 7:59 am
Posts: 0
Free Member
 

Very very cool!

 
Posted : 04/12/2021 8:05 am
Posts: 499
Free Member
 

That. Is. Amazing.

 
Posted : 04/12/2021 8:08 am
Posts: 6874
Full Member
 

as the home made compressor wheel is limited to ~95k RPM.

Huh?

 
Posted : 04/12/2021 8:15 am
Posts: 2642
Free Member
Topic starter
 

as the home made compressor wheel is limited to ~95k RPM.

Huh?

The limiting factor is the stress in the turbine disc which is operating at 5-600°C. The stresses due to centrifugal force peak at the hole in the centre of the disc, and are approaching the yield strength of the material - go too fast, and the disc bursts!

I believe that decent stainless steel (310,321, etc.) is usable up to ~80,000 RPM, but suffers from creep in the blades. The turbine discs for commercial model engines are vacuum cast from temperature resistant nickel alloy (Inconel 718, I think) which is both very strong and very resistant to creep. Turbines the size of mine seem to be very reliable up to ~130,000 RPM.

The best material I could lay my hands on was a nickel alloy called 'Hastelloy X' - it's better than stainless, but not as good as (say) Inconel 718. I came up with my own RPM limit based on comparing the various material properties.

 
Posted : 04/12/2021 1:05 pm
Posts: 1908
Full Member
 

Chapeau

 
Posted : 04/12/2021 1:34 pm
 Joe
Posts: 1705
Free Member
 

Meanwhile i've checked instagram about 1000 times. I wonder if my generation will get anything done ever? Chapeau.

 
Posted : 04/12/2021 1:51 pm
Posts: 0
Free Member
 

If you want to make stuff, then start making stuff. You will learn.

Love this mentality! Just jump in the deep end and learn to swim.

 
Posted : 04/12/2021 3:21 pm
Posts: 0
Free Member
 

you want to make stuff, then start making stuff. You will learn.

Takes on an ominous tone when you are talking about melting metal. You end up with your workpiece welded to your clamps and the worktop on fire.
Or in the case of a homemade spot welder, blacking out the entire county. Which is okay cos the neighbours could keep warm from the embers of my house.

 
Posted : 04/12/2021 6:58 pm
Posts: 5746
Free Member
 

It's not pointless, discovering how things work for yourself is important learning. Noisy.... Yes but a cop noise!. Polluting, not fuelled on butane but....well yeah.
. Completely awesome though! I'd never have thought it possible to make in a shed. Hope balanced does it need to be?!! To run at 85k rpm!

 
Posted : 05/12/2021 4:00 pm
Posts: 17915
Full Member
 

Amazing. Scary, but amazing 😂👌

 
Posted : 05/12/2021 4:30 pm
Posts: 877
Free Member
 

Just thinking about Rolls Royce firing a load of chicken (I think to simulate a bird strike), into the engine for an A380, just to break all the fan blades off and to make sure that the outer casing did not rupture and contained all of the energy and thousands of loose bits of metal.

 
Posted : 05/12/2021 6:26 pm
Posts: 2642
Free Member
Topic starter
 

Thanks for the interest and nice words 🙂

Ho[w] balanced does it need to be?!! To run at 85k rpm!

As good as you can get it! 😀

It's only been statically balanced - the compressor wheel is a commercial turbo part and should be very well balanced already; it is a shrink fit on the shaft so it should be concentric; and I did my best to make sure that the shaft was true (machining between centres, etc.), so if everything is assembled carefully (and all the spacers, etc. are dead parallel), the only thing that *should* be out of balance is the turbine wheel.

The turbine wheel, shaft and rear bearing are balanced as an assembly - you can rock it in its bearings to find where it settles, then grind a bit more off the blades in the heavy spot.

The balancing method that worked best for me was one described in Kurt Shreckling's original book: You hold the bearing at the back of the assembled shaft / turbine between finger and thumb, gently spin the turbine up using compressed air and feel for vibration as it slows down. You then repeat the test with a small piece of tape stuck to the turbine, moving the tape around until you find the spot where the vibration is least. If this is better than the bare disk, then you grind a little bit off at the opposite side to the tape, then go again. When you get close, the lack of vibration is really noticeable.

It sounds long-winded, and I wasn't really looking forward to it, but in the event, it went quite quickly - a couple of short afternoons and I got to the point where I could tell the difference when a double layer of strapping tape (~120g/m^2) about 8mm square was added at the root of the blades (R=22mm). I've just worked out that this is ~0.03 gram.cm = 0.013 gram.inches which sounds surprisingly good - I suspect some luck was involved. It really surprised me how smoothly the turbine ran.

(There is a containment ring built into the rear of the engine, btw!)

 
Posted : 05/12/2021 8:06 pm
Posts: 33325
Full Member
 

Chuffing amazing! Somewhere I’ve got the plans and instructions for building a pulse-jet, but I’ve never had the means or facilities to make one. 😕

 
Posted : 05/12/2021 9:14 pm
Posts: 0
Free Member
 

Disappointed at the lack of single-crystal fan blades... it's like you're not even trying!

When I opened the thread I assumed it was assembled from a kit and you were being a bit grandiose saying you had 'built' it, but no - amazing bit of work. All the chapeaux!

 
Posted : 06/12/2021 8:59 am
Posts: 2642
Free Member
Topic starter
 

Thank you! 🙂

Somewhere I’ve got the plans and instructions for building a pulse-jet, but I’ve never had the means or facilities to make one.

I’ve been hoarding pulse jet plans too, and now I have a welder 😉

Now that really would annoy the neighbours!

 
Posted : 06/12/2021 9:03 am
Posts: 7033
Free Member
 

Very, very well done.

Needs a:

Boomerang

 
Posted : 06/12/2021 9:19 am
Posts: 33325
Full Member
 

Right, your next challenge, should you choose to accept it, is to build two more, and mount them on the back of a car. Like this bloke did with his Tesla!

https://uk.motor1.com/news/552659/tesla-models-jet-engine-acceleration/

🤣

 
Posted : 06/12/2021 8:06 pm
Posts: 9180
Full Member
 

This is amazing work!

 
Posted : 06/12/2021 8:38 pm
Posts: 6312
Free Member
 

Best thread on mig welding!

 
Posted : 06/12/2021 9:01 pm
Posts: 5746
Free Member
 

I'm glad it's got containment!

 
Posted : 06/12/2021 9:40 pm
Posts: 11605
Free Member
 

That mig welding thread has turned into a right time sink with more than a few tangents.

 
Posted : 06/12/2021 11:35 pm
Posts: 2642
Free Member
Topic starter
 

That mig welding thread has turned into a right time sink with more than a few tangents.

Sorry about that ! 😀

 
Posted : 07/12/2021 12:56 pm
Posts: 2977
Free Member
 

Brilliant. I would be dead within seconds of attempting this!

 
Posted : 07/12/2021 2:07 pm
Posts: 3231
Full Member
 

I was ready to point out that assembling stuff isn't the same as making stuff, but you made it - very impressed!

 
Posted : 09/12/2021 10:34 pm
Posts: 11605
Free Member
 

Sorry about that ! 😀

Don't be, I've enjoyed it immensely.

 
Posted : 10/12/2021 12:19 pm
Posts: 2642
Free Member
Topic starter
 

After something of a hiatus, I got my act together and set the engine up for liquid fuel.

It works! 😀

 
Posted : 11/04/2022 4:29 pm
Posts: 91000
Free Member
 

Did you ever figure out how much thrust it generates? Assuming not a lot unless your Workmate is securely bolted down.

Mount it on a little truck held back with a spring, and calibrate it with weights and mark a scale on a piece of tape on the bench. Should be easy.

 
Posted : 11/04/2022 4:58 pm
Posts: 2642
Free Member
Topic starter
 

Did you ever figure out how much thrust it generates?

Not yet - I intend to mount it on drawer sliders (or similar) and use a luggage scale similar to what you suggest.

It's supposed to generate about 40-50N thrust (the higher figure at 105,000 RPM which is probably higher than my turbine wheel will withstand - I reckon 98,000 revs - so I'll be pleased if I get >4 kg).

One step at a time though - it needed liquid fuel to develop any power at all, now I've got to sort out a reliable tacho and more volts to the pump so I can take it closer to disintegration 😀

 
Posted : 11/04/2022 5:52 pm
Posts: 13601
Free Member
 

Amazing!

 
Posted : 11/04/2022 6:23 pm
Posts: 33325
Full Member
 

Certified awesome! Lovely work, that’s a piece of sculpture, even when it’s not running.
Somewhere I’ve got a book from back when I was at school with plans for a pulse jet, which I always wanted to build, but never had the means, nor skilz, to ever really carry it off.

😎👌🏻🎩

 
Posted : 11/04/2022 11:25 pm
Posts: 7033
Free Member
 

I do love the still frame that youtube has chosen for you.

Is it possible to run one of the commercial ECUs on this?

Did you ever figure out how much thrust it generates? Assuming not a lot unless your Workmate is securely bolted down.

From experience, about 3kg of thrust will start to make an unweighted workmate a bit wobbly. A few bricks on the base / bag of soil / sack of spuds / etc, will stop it going anywhere. Doesn't need to be bolted to the floor.

 
Posted : 12/04/2022 8:40 am
Posts: 2642
Free Member
Topic starter
 

I do love the still frame that youtube has chosen for you.

Is it possible to run one of the commercial ECUs on this?

Thanks 🙂

(Spoiler alert: It wasn't youtube that chose the thumbnail 😉 )

I suppose that it could be used with one of the commercial ECUs, but it currently lacks all the bells-and-whistles that the ECU would expect. Off the top of my head, I'd need to add an electric starter; electronic RPM sensing; a glow plug or sparker for ignition; more permanent EGT probe; gas solenoid; and probably a pukka metering pump - it's not a route that I'm intending to go down currently.

I'll add a bit of weight to the Workmate next time... Just in case. 🙂

 
Posted : 12/04/2022 11:20 am
Posts: 7033
Free Member
 

Fair enough, I did wonder how much additional widgetry they might need. Stick with analogue 😉

 
Posted : 12/04/2022 11:25 am
Posts: 91000
Free Member
 

If I were you I'd also consider adding eye protection!

 
Posted : 12/04/2022 11:48 am
Page 1 / 2

6 DAYS LEFT
We are currently at 95% of our target!