RE: JetJoe OWNERS thread
 

Sorry Paul,
I'm quoting prices from Jet Hanger Int'l for the fella in the States. You're SOL in the UK when purchasing from JHI. VAT ya know!
Same place I got my WM44 Gold full autostart from too.

Seeya!

Dave

[/quote]

Dave

The dreaded VAT [:@] thats the 17.5% local tax surcharge. I'm coming over this year and might buy the MW44 your side, just an idea I could have run it up, thens its used and 2nd hand. A saving of $700 would help on tickets etc. Hmmmmm this MW44 might yet fly, though not in my travel case.;)

Paul
RCdriver01


[/quote]

:-))

Dave

RE: JetJoe OWNERS thread
 

Dave

This is really still on thread, as making the case for the relative values of a 2nd hand turbines must be a serious factor between a MW54 mkIII and a JJ14000 when buying outside Europe within Canada, USA and Oz.

A full spec JJ-1400 Assembled + Full auto Fadec unit is about $1500.00 delivered.

A best buy MW mkIII at $1895 is say $400 more but then look at 2nd hand values. The JJ1400 falls to about $950 simply because any buyer can get a brand new JJ with a factory warranty for little more and lots of peace of mind. In Europe its even worse selling a JJ-1400 as the debacle within 'Jet Power' when the German Jetjoe Rep said 'Baby Joe was discontinued' had all kinds of impact in buyers minds.

Given that most JJs below #650 are suspect regarding pumps, combustion chambers and fuel rings any long term reader is going to discount his 'offer price' to allow any upgrades to the 2nd hand JJ-1400.

Consider the USA bought MW mkIII for $1895 then after a year its worth what? Well in Europe your 10-15 hour MW turbine is still worth $1900:):), in fact just recently I have seen sold MW turbines with no ecu, pump or running gear for $1300 for a bare turbine. If you now consider the engineering facts with Wren at a 'Rolls Royce' standard, developing R+D, customer service and performance, it would be hard to justify not going with a MWmkIII.

I can say this having owned four jj-1400s, many other brands including Wren its not even a close call for you jet guys over the big pond. Before salvos are fired, I'm happy to start a new thread since this one is really about supporting JJ owners and operators.
Does ET have a view on this??

Paul
RCdriver

RE: JetJoe OWNERS thread
 

Hi Paul.
I was reading the post about the JJ turbines and although i am not even close to be familiar
not to mention experienced:D with rc turbines, i can add another side to the story that has to do with financial conditions.
If the full autostart + accesories+bullet starter+flightworks pump JJ1400 wasn't available for 1300 Euros delivered i wouldn't had bought anything ressembling a turbine because simply i cannot afford it.
The extra money needed to buy a Wren are not available to me now or in the future i am afraid.
I dont know how much guys in USA are making but i have a decent job and i make 16000 Euros per year!
That is ~19000 dollars per year after working for full 22 years and 400 or 500 more dollars are a big amount for me.
I must admit though that i save a lot of money because i am not married and i have my own house.
I had to buy everything needed to get me going like the electronics, pump, etc. and for a Wren i had to pay over 2400 Euros.
Right now i am happy although i have not even tested the engine (i hope it works, otherwise i will commit suicide:D ) and honestly if i get 12 lb of thrust and an operational time of more than 10 hours i will be jumbing up and down with joy.
Please do not think that i am trying to look wise or something, i just describe what made me decide to get the JJ1400.
I immediately fell in love with a Jetcat (i like the name also) but when i saw the price i decided to erase the link from my computer because i couldn't sleep knowing that it is out of reach for me.
Btw i went out for turbine oil today and i found nothing so i got a quart of AMSOIL fully synthetic TCW3 two stroke oil.
I dont know what exactly to do as i am afraid of the health issues with turbine oil but i dont want to use oil that
it is not specified for the turbine.
I read that TCW3 fully synthetic oil will do the job but i will try some harder to find a real turbine oil.
Anyone knows an online store in Europe that sells turbine oil?
Chris

RE: JetJoe OWNERS thread
 

Chris

None of my post really applies to us jet flyers within Europe, I like you went for the JJ-1400 for cost and because I could resolve most technical problems with existing equipment. The option for me was looking forward to twin turbine flying leading to my dream project an 'English Electric Lightning' with two JJ-1400 giving 25lbs thrust upto 28lbs is nearly as good as after burners.[8D][8D]

The option for those not with in the EU, is to look at the whole fiscal picture, I know if I had the the USA option to buy, operate and then sell 2nd hand into the EU and recover my costs I'd go exclusively with Wren, its that simple.

I'm more than happy with the JJ-1400s and know enough to get the max power from them without any tears. Resale wise as more people fly and operate Jet Joes successfully then resale values might be better.

Paul
RCdriver

RE: JetJoe OWNERS thread
 

Yes Paul i understood what you ment, i just wanted to say my opinion cost wise (from a poor mans side:D ).
I am not usually selling back anything i buy (i like to keep my things and take them to my grave :D)
so as long as it works is fine with me.
If i was living in USA as i once did i wouldn't hasitate to buy a known brand turbine but now i am forced to
look harder before i buy something.
I am not complaing though, i like the lifestyle here:D
Chris

RE: JetJoe OWNERS thread
 

Dave,

Please keep in mind that I don't want this to degrade into a shouting match. I see what you see on JHH's site, and you are correct, for a kit that is. Yes I see I misquoted the price of the Wren 54. I inadvertantly quoted the SS version. Since I have no experience with turbines, I figured it best to go with a fully assembled version. While i can rebuild car engines, and am an engineer, I decided to shy away from the kits. JHH's fully assembled versions say "Call for pricing". This screams "Expensive" to me. Now, let me ask you this. How involved is to assemble a kit? Can your typical mechanically inclined DIY'er do it with standard tools?

Thanks,

Jorden

RE: JetJoe OWNERS thread
 

Just wanted to put my experience forward on building the JJ1200 kit.

I am a motorcycle mechanic by trade and decided to give the JJ1200 kit a go - I also saved a small amount by going the kit route and upgraded to the bullet starter with some of the savings.

The kit is pre-balanced from the factory.

I was lucky enough to have a review of an MW54 kit in a recent turbine magazine at hand which helped a little with assembly. To be honest, the kit is very easy to assemble. From start to finish it took me around 4 hrs to assemble - that's with a couple of trial fits of the turbine wheel and compressor wheel before final assembly.

The motor started and ran without any problems whatsoever and this is my first turbine ever. It's very enjoyable to build and even more enjoyable when you first run the turbine.

In my opinion these turbines are very easy to put together and even more satisfying to operate - all for a very reasonable cost!

At the end of the day, you pays yer money and takes yer choice - it's as simple as that.

Rabbit.

RE: JetJoe OWNERS thread
 

http://www.rcuniverse.com/forum/m_26...tm.htm#2600920

Dave

RE: JetJoe OWNERS thread
 

Four hours seems to be the average time for building the kit turbines, with no special tools.

RE: JetJoe OWNERS thread
 

Dave,

Thanks, that was an excellent link.

Jorden

RE: JetJoe OWNERS thread
 

Chris

I'd bet its great to fly in your part of the world, not to mention the weather. I planned to to fly here today but there is 30mm today in my part of England and while I can melt the snow with the exhaust [8D][8D] the drag will be too much to RoG and fly. Its great to hear and read so many other people enjoying operating their JJs turbines. Two years ago some jet guys here struggled to convince readers that their JJs ran and got airbourne.

Its strange but I'd bet a glass of the good stuff that when you go down to your flying field, people will strangely think you must have won the Euro Milions or have mega bucks by running up a turbine.:)

Paul
Rcdriver

RE: JetJoe OWNERS thread
 

Paul
I just returned from our little rc gathering.
They already think that i must be hiding something financialy speaking.
They just can't accept that for 1300 Euros i got a complete turbine engine.
They keep telling me that i will have to spend a fortune in accessories, auxilliary
equipment and hidden expenses.
I just can't convince them that in this price i got everything exept fuel and oil.
Btw one of my budies couldn't give me back the jj1400 when i show it to him.
Believe it or not the main reason for our meeting was for them to see the turbine:D
The weather here is rainy but for most of the year the conditions are suitable for flying.
We even flew today just before the rain.
Chris

RE: JetJoe OWNERS thread
 

JetJoe Turbine Builders.

Anyone tried to double lube flow rate and half their oil content to 2.5%?

For those who like to read the oil specifications for turbine and TCW3 oils, its best to remember we burn and combust all our oil in our minature turbines, totally unlike full size aviation, ours is a 'total loss system' with temps well above flash temps specs. In this regard it is akin to putting known nasties into a salamader or kero space heater, not recommended by any oil company. Both Wren I believe and the GTBA recommend TCW3 oil like 'Quicksilver'.

Its fair to say that stripping a four stroke IC engines is much more difficult than building a kit turbine engine. Its obvious that if a kit is available with two allen keys, needing you to purchase two spanners (torque left) then with little mechanical knowledge and lock thread you can build and strip your turbine. It now takes little time to remove mine from the air frame, strip down, rebuild and refit to air frame, for me about just over two hours.

For those who want more power from their JJ-1400 its possible by upgrading the diffusser and compressor wheel profile, this is only worth while if you already have the latest inconel chamber or have retro fitted a inconel six stick chamber. As stated earlier here on this thread it is possible to get more than 14lbs thrust from a standard JJ-1400 but it is how you do it. Also if this then nullifies factory warranty or your insurance cover if an accident occurs.

Paul

RE: JetJoe OWNERS thread
 

One last thing before i fire it up.
Can someone share with me the Fadec settings for the JJ1400 with flightworks pump?
I must double check those settings as i feel a little worried now that the time is near:D
Also how you vent the main fuel tank? Do you fit a check valve for tank breathing?
Chris

RE: JetJoe OWNERS thread
 

Hi Paul.
I tried to just start the starter motor and i saw something strange.
I didn't connect any gas or fuel(everything else is connected), just tried to make a simulation before the actual testing.
Here is what i saw:
The gas solenoid is energized and the rpm meter shows ~64000 rpm.
The starter motor kicks in and the rpm meter looks like it shows the actual rpm but it only goes
up to ~2500 rpm and then the starter motor shuts down.
After the starter motor is shut down the rpm meter shows ~64000 rpm again (64000 ~ 45000 but basically random numbers)
When the solenoid is de energized or i hit the throttle cut (trim low) the rpm fall to 0 again.
It looks like and feel like noise from within the fadec as it shows the same behavior when i unplug the solenoids.
This erroneus rpm reading is happening only when the gas solenoid is energized (i dont know about the fuel solenoid as
it does not get activated).
Is this behavior normal?
I feel like something is not right but i may be wrong.
Any help is most welcomed.
Chris

RE: JetJoe OWNERS thread
 

Chris,

.. make sure your two cables to the glow plug are twizzled together...;)

Dave

RE: JetJoe OWNERS thread
 

Hi.
I found also that the glow plug wires were causing the trouble so i twisted them together and added a toroid just to be sure.
The problem went away after that but is this normal?
I guess you have encountered the problem before.
I am all set to go.........
Chris

RE: JetJoe OWNERS thread
 

Toroid...?[8D]...whats this ..?..:).. A Ferrite ring maybee ..?..:)

Yes it is normal if you dont twist the wires together .... ;)

..without the twist they create a magnetic field that interferes with the Hall effect sensor..

RE: JetJoe OWNERS thread
 

Chris

When the rotor doesn't move, so that it doesn't generate a RPM signal, the amplifier on the magnetic sensor goes to maximum gain, and can pick noise from the supply line, solenoids, glow plug etc. with powerful digital servos and weak 4,8V batteries it is possible that the supply voltage drops this can also cause bad readings.

As soon as the rotor turns, its signal is much higher than the noise and all is OK. Remember that the initial spin is only slow to 2500 rpm just to mix the gas and air up when the temp jumps above 100c and with 'gas on' then the rest of the start begins and higher rev are given. Treadstone is right in suggesting wrapping glow cables and also separate as far as possible the electrical items.

Paul
RCdriver

RE: JetJoe OWNERS thread
 

Yes that's what i was thinking that it might have an internal amplifier in it so when no rpm are read it goes to max gain and it picks up noise, although i had my doubts as i didn't knew which Hall effect cirquit it uses or where the gain amplifier is located, inside the Fadec or the Hall effect sensor.
After i removed the rpm sensor cable all interference went away so i started searching the cables.
That explained why when the turbine rotor was turning the rpm were right.
Yes Treadstone i meant a ferrite ring.
What, does the word toroid means something else, nothing at all or i mispelled it?
Thank you guys for the help!
Now i am in bussiness he he he, time to wake up the neigbors tommorow morning (Saturday):D:D:D:D:D
Chris

RE: JetJoe OWNERS thread
 

..Toroid :).... of toroidial shape..;) ... Donut shaped to you and me Chris :)...Yum...;)

RE: JetJoe OWNERS thread
 

Ok now.
I got the right gas, the right valve, the right fuel, those new 50 micron Festo fuel and gas filters, some Festo check valves,
Plenty of Festo fuel and gas lines and two final questions.
The Festo fittings are push in as i found fittings.
1) Are those fittings good for gas connections also?
2) I am tempted to replace the NiCd original suppled 1800mah battery pack with a two cell 2100 mah lipo pack.
Does anyone has done that? (i am sure that someone or all of you have done it :D
Together with a low drop linear or switching regulator for the rx (6~8,4 to 5 volts) it should save a lot of weight when fitted to the plane.
I am thinking to fire it up for the first time tommorow morning at 06:00 :D:D:D after i put on my bullet proof vest:D

Chris

RE: JetJoe OWNERS thread
 

Festo fitting are fine for the gas supply side. Not used a regulated lipo as yet, so no real experience to report.

Paul
RCdriver

RE: JetJoe OWNERS thread
 

Dont worry i will try it and report back.
I realy like lipos.
Thanks Paul
Chris

RE: JetJoe OWNERS thread
 

Here is my setup showing it to some friends.
i didn't even wanted a picture but the jj1400 draw much attention here anyway.
Still waiting for the festo filters to arrive as i want to do a good job from the start.
Chris