Electrical control box

I am busy at the moment designing and building the electrical control box for the twin and when that is complete 'and safe!!' I will be attempting further live tests on the engine. I am fitting a multi plug and socket arrangement on the box and on the engine so they can both be completely disconnected from each other and the loom.
Propane tests have been done and it makes a lovely DEEP roar when struck up with this :) It will not actually self sustain under Propane but it's there to get everything hot before actually running the liquid fuel.

Propane injection valve.

Just added a few more pictures of the Propane injection valve in the side of the CC.
The flame is lit before starting. I have tested to see if the starter motors running the compressor turbines put out the flame and they don't. It seems to work very well. The idea is to start the engine with the flame ignited inside the CC/FT to ignite the liquid fuel quickly thus eliminating fuel pooling.

Picture from the shed door looking inside :)

The completed system.




This device below is to be the start solenoid injector. It is off of the choke start from a Ford engine and will serve the purpose well. I have to decide whether to fit it next to the main nozzle or next to the igniter plug to spray fuel or Propane for starting only. The solenoid will only operate when the igniter is lit thus igniting whatever fuel I decide to use.

Fitting the CC drain

I needed to fit a combustion chamber drain so I got a 1/4bsp coupler and cut it in half. I then drilled a suitable hole in the bottom, front of the CC.






I then TIG welded the coupler to the CC and added a shortened right angle pipe olive gland.

This feeds down into a 12v solenoid and out to a fuel drain canister (eventually)

Propane start system and CC drain valve

I have come to the conclusion that during the start up the other weekend I had a 'run away' situation caused by excess unburnt fuel pooling into the combustion chamber bottom caused by the fuel not igniting quick enough thus allowing it to fall to the bottom of the CC.

SO.....


I have been tinkering in the shed again this evening and found what I think may be the answer to my starting system problem. I have taken a video of what it is and how it's too work, below. It's a cold start (choke start) solenoid spray valve from a Ford engine. It's been sat in my 'fuel bit's' draw for ages and it just caught my eye as I was ferreting through earlier. If I add low pressure propane to the fuel in end and supply 12vdc to it it has a lovely wide spray of propane emit from the end. I have decided to fit it right next to the igniter plug so it sticks into the CC side wall and sprays more or less straight onto the plug. The 12v supply to the said solenoid will be taken from the igniter feed so that whenever the igniter is excited, so is the gas valve thus firing any liquid fuel almost instantaneously.


I have also found that I can indeed find enough room to drill a drain valve into the base of the CC ( upon looking the other day it didn't occur to me that I could remove bit's to gain access) I removed the CC to turbo piping and there is enough room there to enable me to get a drill and my TIG welder in. I shall have a right angle bend straight onto the CC and then after a short bit of pipe (to alleviate heat damage) into a 12v solenoid valve. When ever I need to drain the CC it's just a case of pressing a button on the control panel.

http://mysite.orange.co.uk/smogthemog/GasNozz.wmv (15Mb)

Picture below of the bottom of the CC with just enough room to drill and TIG a drain valve (with the piping removed) :)

The Combustion Chamber internals after the run

Nice swirl pattern in the carbon deposits on the back of the nozzle plate.

It RUNS :)

I have spent a good 5 hours on the engine today and got it running to a degree. It spooled up for around 4 seconds until I bottled it and hit the fuel cut off switch.

I have spent most of the day trying to start it on diesel/petrol mix and hadn't had much luck. It kept firing but just lots of flame and smoke. I then decided to try neat diesel and it fired up first time. Lots of flame again but then it caught and began to spool up. The noise was awe inspiring with a very very low, stomach shaking growl on spool up followed by an ear splitting whistle when things speeded up a little. It was nearly too much for my Peltor ear protection!

I unfortunately have no data as of yet and no video as my camera is around my brothers house on a lend but I took a few photo's of the aftermath.

When the engine did spool up I had to stop it from toppling over in it's frame as the power was just amazing. The engine and frame it is all sat in is far to heavy for me to lift and it was more than ready to push it's self over. Luckily I had welding gloves on and stopped it when it tried.

I have a few fuel leaks to sort out, TIG welding cracks on some of the CC joints, wiring to tidy up further and to grow some bigger balls for myself before the next test.

Lovely stained stainless :)

Fuel non return valve / Oil pressure switch.

Looking back this evening over the blog it has come to my attention that many times I have written that I am going to do this and that but when it comes to it I have done it all a completely different way! Sorry for the confusion but It's all part of a massive learning curve and this is a BLOG - a sort of online diary of events of how I have dealt with the building up of this monster.

Your comments are ALWAYS welcome.
Thanks
Jim

The fuel non return valve. This should stop the fuel returning into the tank and emptying the fuel filter/pump arrangement every time the engine is at rest.

This is the variable oil pressure switch which will have it's 12vdc feed taken from the fuel pump output of the relay bank so that if the oil pressure drops below 20PSI (only when the fuel pump is running) then it will trigger it's switch and send a 12vdc signal back to the Tacho board thus shutting down the engine. I will have to invert this output using a simple relay circuit because the switch is N/O (this means that when no pressure is applied to it the contacts are in the open state - it's only when you apply pressure over the set point (set with a small screw at the top of the switch) that the contacts then close so in order for it to give a 12vdc output when the pressure drops, it needs to be inverted.

Just some general layout pictures.

Over this weekend I am aiming to complete the electrical side of things for the test. Tidying up the wiring and fitting the temp controller is also on the list.

Fuel lines in place

The copper fuel lines are now all in place with the 6mm bore from the top of the pump to the back of the nozzle and from the outlet of the prop valve to the inlet of the fuel filter.

Fuel return from the prop valve. I may need to fit a non return valve here to stop the fuel in the fuel filter from draining back into the tank.

The mish mosh of wiring that goes with this thing! And that's only a part of it ;)

Final bits to do before testing.

All I need to do now is to copper pipe the connection from the top of the fuel pump to the nozzle, copper pipe from the oulet end of the prop valve back to the inlet to the fuel filter, mend one of my starting routers as the clamp for holding in the socket fixtures I made (earlier in the blog) has bust. I think I need to get a new one! Grrrrr
I have to fit the oil pressure switch and I have a bit of wiring to complete for the fuel pump and temperature control.

It looks like it should now be in the next couple of weeks when I will be properly trying it out.

Oh - I needs to get some fuel too!!

Nozzle testing (again!)

I know I have already done this earlier on in the Blog but I wanted to do some final setting up of the proportional valve parameters before lift off. I wanted to make sure that open was fully open and closed was fully closed. There is a set up procedure that comes with the prop valve controller and certain steps you need to stick too to get it correct.





I used compressed air to simulate the fuel (it's a bit cleaner :) ) flow and all seemed to work fine.

The final nozzle arrangement showing the CC pressure (P2) guage and the 24vdc proportional valve for the nozzle fuel bleed off.

Just some pictures of the flame tube out of the combustion chamber.




The below picture shows the CC drain hole and bung. This is to drain any excess unburnt fuel off that may pool in the bottom of the CC that could cause untold problems when you are desperately trying to shut down the engine!!

The flame tube situated inside the CC and held in place with the FT retainer.

Cleaning of the combustion chamber internals.

A bit of cooking in the kitchen!

I used the kitchen gas stove to anneal the copper water jet cut sealing rings, used either end of the combustion chamber.

October is looming and things are moving in the W/S again :)

I have finally got around to a bit of 'in the shed work' as of late and have been tittavating things up a bit before the first run. Below shows the cutting and laying of the copper hot side gaskets to seal the turbocharger to the twin exhaust manifold.

I have renewed all the bolts and have added Aeroquip locking nuts. These nuts are ideal for high temperature applications as they lock onto the bolt as with a nyloc nut but they don't contain nylon, which would obviously melt!

Below is the fitting of the fuel pump and filter. The filter is the old filter I took off of my Audi S6 car and after re-tapping the outlet hole to half BSP, it fit's just perfect.

Cleaning up + adding the combustion chamber temp sensor.

I have been doing a bit to the engine over this weekend. I have fitted the T3 temperature sensor in the outlet from the combustion chamber to the two turbo units. I have tried to keep the sensor nipple as close to the outer casing as possible to avoid it being melted off on any hot starts I may incure.
I have also been die grinding and finishing the inside of the combustion chamber outlet splitter pipe and externally pickling and cleaning the casings.

Inside view of the Flame Tude inside the combustion chamber.

The two compressor outlet pipes being pickled (a process of brushing on a very strong acid that cleans the TIG welding burn marks from the Stainless Steel)

Inside the Flame Tube. The fuel nozzle, at the bottom, and ingiter, coming in from the left hand side, can clearly be seen.

Tacho sensors are now all fitted

I have been testing the tacho system out tonight after finally getting the shaft nuts painted and the fibre optic sensors in place.

Just added a video of me demonstrating the starting technique for testing, using the two routers. The Oil is running at 40PSI.

http://mysite.orange.co.uk/smogthemog/Default_1.mpg

Below are the two 30000RPM routers wired in series which I will be using to primarily start the twin.

I have tried spinning the turbines up using them, running at 60PSI Oil pressure, and they work excellent !!!

The two 16mm sockets fit the two domed nuts on the end of the turbine shafts perfectly with a good amount of free movement so as to not put too much lateral strain on the bearings. The sockets have a countersunk 8mm A2 SS Allen bolt through them, tightened, locktighted and then the out shaft lathed to 6mm to fit the routers.






I refitted the end plate to the end of the combustion chamber and added the P2 gauge. If the gauge suffers heat stroke there then I will be adding a short copper pipe to spacer it away from the CC end. It's only there temporarily anyway, just for testing purposes.

Getting the combustion chamber ready for firing up

I have been getting the Combustion Chamber ready for the oncoming fire up. The return nozzle has been cleaned (gathered a fair bit of gunk on the gauze during water testing) and I have fitted the brass nozzle holder to the end of the CC. I re-cut all the threads and De-burred the holes whilst it was all apart and after first tests I will be removing the Flame Tube and tidying that up a bit also. All flat mating steel to steel faces will be Carborundum paste and a glass sheet polished to ensure they are flat creating a no leaks joint. The whole frame, turbo's, Oil tank etc etc will all be dismantled after first testing and all polished and painted up. There is no point in spending time doing it all now until I have found out if the engine is going to run OK and amended any problems.

I have been fitting the fibre optic tacho head sensors to the compressor scroll's and mounting the optical decoders nearby.

The copper pipe will be bent towards the original knurled shaft nut when complete and that nut will be half painted White / Black.

I have decided to run tests on the engine very soon and I will be starting it using 2 modified 16mm 3/8th drive sockets each fixed to a 30000RPM router. The routers will be wired in series so they will both run at 115V as opposed to 230v so they should run approximately at 15000 RPM. The 16mm sockets will be hand pushed onto the 16mm stainless steel domed nuts on the ends of the shafts. At 10RPM the Oil pump will start to ramp up and build pressure to approx 60PSI over a time period of 20 seconds.

And then:

Fuel turns on @ 3000RPM

Fuel turns Off @ 65000RPM

Ignition On @ 2000RPM

Ignition Off @ 20000RPM

The engine (fuel) will run until either the fuel runs out, high temp is reached, Oil pressure drops below a set value or an E-stop is pressed.

If an E-stop is pressed then this will totally shut down everything, even the oil.

A picture of the PRV I will be using and the 2 Temperature controllers that I will be using to keep an eye on 'hot' things :)

Some pictures of the tacho unit as supplied by Russ Moore @ Badbros Racing www.badbros.net

I am going to try a 6 Bar Pressure Release Valve in the oil system line and see what that will do - I will attach it with a Tee junction to the feed out to the oil pressure gauge that way it will not ruin the Speedflow hose set up too much.
90Psi has got to be safer than 200Psi !


I did some more tests last night with the fuel nozzle/proportional
valve set up and found that when I totally removed the proportional
valve from the nozzle return feed there still wasn't enough return
flow to reduce the nozzle mist down to a required level. It seems
the return feed is restricted inside the return nozzle housing. I
may have to drill it out in order to get the required return flow to
be able to have enough 'swing' in the final output fuel levels into
the CC.
I also tried the new 2mm aperture prop valve but it struggled to be
able to hold back the pressure from the pump once opened. Worst
comes to the worst I will run both valves in parallel hydraulically
and electrically, that would then give me 3.6mm of aperture to play
with.

I have acquired 4 stainless castle nuts and am going to try and
manufacture my own Bendix arrangement incorporating the nuts where
the side faces of the castles are chamfered in a way that they will
engage one way and release turning the other.
If the Bendix arrangement wont work then I will have to resort to a solenoid arrangement where the solenoid moves the castle spigots in and out of mesh.

First Oil Test Go Ahead

Tonight, after tightening up all the Speedflow connections and adding an oil pressure gauge, I filled the tank to the required level of oil and added some volts to the oil pump. At 24vdc the oil pressure is around 200PSI which is obviously far too high and I noticed a very small trickle of oil behind the turbine wheel of one of the turbochargers so I quickly switched it off !
I then tried the pump running at 12vdc and was getting around 100PSI which is still too high so I then introduced the ESController into the equation and have now got adjustable pressure from 10-100PSI. The pump at 60PSI seems to only just be ticking over and what I find a little strange is that according to the details on the side of the pump motor it should only be able to deliver 60PSI (4Bar) at 24vdc ?

Oil cooler now piped up.

I got the Oil Cooler all piped up tonight and started to think about proof tightening all the connecting fittings then filling with Oil. I will be using a Synthetic 5W - 40 Oil which I purchased off of EBay.

Speedflow Oil Pipes & Connections

Tonight I have finally got the Oil cooler mounted and the stay mounted for the Oil splitter piping.


I haven't yet piped the cooler up yet. As soon as it is done the Oil will be added and the system tested.


The Oil splitter stay.

I now have the new Proportional valve (2mm aperture). It's a bit bigger physically than the 1.6mm !

If I still don't have enough return flow from this 2mm valve (on testing the return nozzle I found that maybe the 1.6mm aperture wasn't big enough and didn't dump enough fuel back into the tank thus not shutting off enough fuel for idle at the nozzle) Then I will parallel the two together to gain a 3.6mm aperture.

The 2mm valve will work from the same controller as the 1.6mm and paralleling them both together shouldn't cause a problem electrically.

Just a few very recent pic's of the engine as it was tonight.



The oil pump.



The Oil filter, oil stat and oil cooler with afixed cooling fans.



Left side view.



Right side view.



Right side rear view.

Update

All the remaining Speedflow oil hoses are now going to be fitted over the next weekend or two. I haven't had a lot of time recently with the new baby arrival so the engine has seen a little less of me just recently.
I think I have come to the idea that the electric start is a no goer! without spending Lot's of time and effort on perfecting the bendix design - Pity because it does look nice. EDIT - 31/05/07 still going ahead with it but using a solenoid arrangement - It needs a device to push the couplings onto the domed nuts harder. The Bendix type friction couplings are just not good enough to spin up the turbine wheels using the bendix action only to rely on enough pressure to create a good mate. The couplings just sit and spin on the domed nuts and have blued them off due to excessive heat. Not Good!
There is also a problem I have with the ESC that where being used to control the 2 starter motors. They have a tendency to shut down if an over current situation is seen. This makes the ESC's shut down intermittently during spool up causing the motors to judder sometimes.


I have recently added some video's on to YouTube of the Jet Kart bit's and Bob's :-











Hope you enjoy them :)

Speedflow

The new Speedflow couplings and Hose have now arrived.





This is all of the electronic parts - minus the tacho, that are going into the build.

Shot of the inside of the new Workshop :O)

Speedflow Hoses

All the remaining Speedflow Hoses and joints where ordered last Friday 16/03/07 from Fay @ Speedflow. They should arrive tomorrow sometime. I can then get all of the Oil side of things up and running and then concentrate on the Electronics.
As usual, I will keep everyone updated on how it all goes.
Jim

15/03/2007 update - Workshop progress - Oil and Start control

Just a quick update as to what is currently happening re- the Twin Turbojet

The workshop shed is all up now and the electricity/lights side of things is all installed. The majority of the equipment is all out of the conservatory now and back in it's new place in the new W/S. I have still a little rearranging to do but's it getting there.

I have decided to go with an RC (radio controlled) type of ESC (elecronic speed controller) for the oil pump electronic power control. The controller will handle up to 28Vdc at 60Amps and will be fine for the 24Vdc 7.5Amp pump. The ESC will ramp up controlled by a small PIC programmed chip board which in turn will be switched on by the tacho board. The reason the Oil needs to be ramped up during the start up procedure is to lessen the load on the 2 electric starter motors. The Oil will be ramped up over 20-25 seconds and the Starters will lag slightly behind the pump.
The starter motors are controlled by 2x 80Amp ESC boards and again, as with the Oil pump, the ESC's are ramp controlled by another PIC board and switched from the Tacho board.

28/02/07 Twin Turbojet Update

I am currently in the middle of a workshop re-size. I was previously in a 6'x8' wooden garden shed (where I stripped and built up the kart!!) and as you can imagine it was a little cramped. I had a compressor, TIG welder, pillar drill, chest of draws (with me bits in), several other jet engines in bits, toolboxes x4 etc etc etc It was all a bit too much so I have invested in a 14'x7' (which is as big as I can go with the available space) which arrives this coming Saturday 03/02/07. I then have the next week off work to prepare the base, erect it and kit it out with the necessary electricity/lights and all my tools back in it !

Currently all my W/S tools, engines and many many other bit's and pieces are huddled around me here in our 12 month old conservatory -it took a bit of persuading the missis I can tell you but they had to go somewhere :O)

Anyway - I am awaiting the digital tacho system to turn up from Russ Moore @ Bad Brothers Racing www.BadBros.net

I have still to work out all the wiring on the engine but cannot really start until the Tacho gets here as I don't yet fully know all the lead outs and stuff so the ball will start rolling just as soon as it arrives. I have the digital proportional valve and controller for the fuel side of things and all the ramp up cct's for the Oil pump and starting motors.

Since collecting the engine I have been collating all the equipment I need to get it finished - it may be a while in the making but it's going to get there.

I have sent off my list of bit's I need to order from Speedflow. I have also been in touch with Colin from Custom carts, the people behind the Golf Buggy for the project and they are really excited about it all !! Colin is still providing the project with an EZ-GO buggy which I have got to get shipped here to the workshop (once it's built !) and then implant the twin into it (once it is running!!!!)

I am really looking forward to starting work on it !

Funds are a little tight at the moment with the new baby arrival and the missis being off work but it will soon hopefully be back on the straight and narrow and things will be getting sorted :)

I will keep you all updated as often as I can about the project :)

I have added a picture below of what the engine will be fitted into once it is up and running

Thanks

Jim

Update

Just a quick update the the Blog.

I have recently purchased a part built Twin TurboJet engine off of Nick Haddock. The engine is 60% complete with the exhaust/afterburner assembly, the fuel system and all the electronic components for control yet to be made/added.

The control system will be hopefully fully automatic with a one touch start and stop sequence with 'Fly By Wire' throttle control when the engine is at operating temperature.

A Few More Jet Kart Pictures

Jet Turbine powered Go Kart

I thought I would add a few pictures of my DIY Jet Turbine powered Jet Kart.
I bought the basis of the kart and engine off of Ebay and have done substantial modifications to it to make it as it is today.
These modifications include splitting the rear axle so to make steering easier as a standard go kart has a solid back axle and unless this axle is driven, can cause difficulty in steering. Splitting the axle creates a sort of differential and it steers around corners much easier especially at low speed.

The jet turbine runs on liquid Propane gas (LPG) and the afterburner runs on a petrol and diesel mix (40 x 60%). Looking from the front, the left hand black tank holds the LPG and the right hand the Afterburner fuel.

Speeds of around 80mph (and maybe higher?) should be possible with the calculated thrust.

As you can possibly imagine, it is extremely noisy and hearing protection has to be worn at all times !

Unfortunately, to date, I have not yet actually sat and ran in it - mainly because finding somewhere to take it is like looking for the proverbial needle in a large heap of straw! The UK is littered with old WW2 runways but getting permission to go on any of them is prooving very difficult. Insurance is also a big problem with everywhere I have contacted requiring some sort of cover.

Turbo Jet Mini Moto Bike

I bought an £80.00 Pocket minimoto bike off of Ebay and I am slowly going to be fitting a DIY Jet Turbine engine into it.

The bike is tiny as you can see so fitting all I need to fit into it will be difficult.

Every available bit of space must be utilized well.

The turbocharger above was purchased for £0.99 off of Ebay and after an overhaul, will be used to build the turbine engine for the bike.

Some of the parts of the turbo prior to the overhaul.

This project is now on hold until I find time to do it ;)