bukeym

Hi everyone,

Attached you can see the photos of the combustion chamber of my JJ1400. I am experienceing high temp problem at high RPMs particularly after 130K. I have checked everything: 1. Balance is perfect 2. vaporizer tubes tested with propane not much difference 3. Startup perfect temp not over 450-500 C. 4. Bearing conditions are OK. 5. Compressor clearance is even perfected with sheets of hysol layers.

So I believe there is only one problem left: Poor vaporisation!... Am I correct?.. I see that the vaporiser tubes are way too short and away from the combustion front cover..I would appreciate some input. Can I find vaporiser tube circle similar to MW 54 ?. Does anyone have spares or any contact for supplying?.

Thanks

WrenTurbines

I have been contacted by someone wishing to buy "the inconel vapour tubes with the circle" for a "homebuilt MW 54". The name and email address of the would-be purchaser is that of the JetJoe dealer for Turkey, Marat Bukey, as on JetJoe's contacts page.

http://www.jetjoe.com/htm.php?nowmenuid=9648

I cannot be sure that this is the mbukey who has posted above, because if it is, the fact that he is a JetJoe dealer should be in his signature line, as per RCU rules.

I have replied to his mail. I have politely declined to supply him and suggested that he buy his parts from Joe.

We would like to make it clear to all JetJoe owners that we will not give any help whatsoever with their engines. Asking Wren about parts to remedy problems with a JetJoe is like asking the Rolex watch company to mend your fake Rolex!

Sara Parish
Wren Turbines

Xairflyer

My Feedback: (1)

Contact JetJoe they will be able to send you another no problem.

I see Jetjoe has a new mini turbine coming out - J Junior only 235grms with 4lb thrust, loads of possibilitys, from EDF's to flying wings ! Have to get me one of those

rcdriver22

My Feedback: (1)

hi Sara

The third JJ national rep to seek help and guidance here on RCU. Perhaps if Jeff Wong aka Jet Joe really had his national reps as real customers he would assist as suggested as per the last post, surely?

I have a UK six stick CC and fuel ring to sell, this will fix the SNAFU JJ1400 till the tolerences kill it running in a work bench after 8-10 of operating in frustration.
Now 99% into Wren and also compliant with Gasper's "no help this thread" on ripped off chinese ECU-fadecs with no JJ back up or assistance (cause they know nowt tech wise)

Paul

akpepp

WOW!

I am speachless! You would have been better off just letting that one go.


Whats a Rolex. Oh yea an expensive timex.

Woketman

My Feedback: (6)

What do you mean that Sara "would have been better off just letting that one go"? Are you suggesting that Wren should NOT attempt to protect their intellectual rights?

akpepp

Sorry guys. I fell for the hate mail trap. I will try to stay on subject.

Woketman

My Feedback: (6)

If anything, Wren should point out these "obvious" things far more often as it appears that Joe does NOT realize it is so "obvious"!!!

GSR

My Feedback: (145)

Well akpepp, its kind of like this-your neighbor breaks into your house and steals your hooch still-he then calls you up and asks for help in operating it-its like that. In my opinion WREN is obligated to NOT help a JJ problem. BTW-From the looks of that POS combustion chamber and sticks its amazing the thing runs at all. Scotty

mchigmk3

Hi everybody

I am a PhD student in UK.I am working in a project that requires jet turbines. I would like to obtain a full technical details and specifications of the series ssupplied by jetjoe or wren in order to decide if they suit our requirements and then to order them. The data aviable in the website is not enough for full engineering requirments. I will be thankful to know if the company provide these details when ordering some engines? for those who already got theirs, do you have such information?? can you end me a soft copy? my emial address is

[email protected]


thanks

bukeym

Has anyone tried this balsa kit with a turbine?.. Any suggestions?

http://cgi.ebay.com/Keecat-65-Bobcat...ntrol_Vehicles[img][/img][img][/img]

bukeym

Has anyone tried this balsa kit with a turbine?.. Any suggestions?

http://cgi.ebay.com/Keecat-65-Bobcat...ntrol_Vehicles[img][/img][img][/img]

Xairflyer

My Feedback: (1)

It is esentially the same as my jetjoe powered Planenutz bobcat other than it has a balsa fuselage, canopy is further back which would make the installation easier. If you look at thier other models the flycat looks interesting.

Xairflyer

My Feedback: (1)

Or what about that Honda HA-420 for two of the new Jetjoe Junior turbines

dw_crash

My Feedback: (6)

Hello Jet Joe owners,

It seems that there have been a few JetJoe with problems. I was wondering if anybody with one of these engines would have the ECU available for sale. I am looking for the FADEC V4 which was shrink wrap with the white Molex connectors, Full Autostart version. If you have one, please PM me.

Thanks,
DW_CRASH

myring

Hi Paul,
Long time no see. I have bought a new fuel pump which is similar to flight works pump from jetjoe. But the worse thing happened to me. The pump has too obvious strong performance on fuel supply than old JJ pump because start EGT went up rapidly to 900 degrees within a few seconds. Long flame out of rear cone scared me. I had to reduce the setting of start point to auto+0 and of start ramp to 001. The second start still failed due to hot start at the end of start phase.
Do you know there is lower setting of start than auto+0 and 001 in REGAL semi-auto ECU? Thanks a lot!

j_rc_heliman

Can we stop the JJ bashing? I mean this forum is for JJ OWNERS AFTER ALL! The Wren fanboy whining is getting really old. I have one of the first JJ-1200s, upgraded to a JJ-1400 and have over 15 hours on it (original bearings) and it runs perfectly. As far as Wren owning intelectual rights on a inconel vaporizer tubes, or any part of the SHREKLING/ KAMPS design is just plain ridiculous, it is public domain knowledge at this point. As a current GTBA member and a Professional Mechanical Engineer I understand the desire for quality and high precision tolerances, and I believe that JJ has done a good job at evolving these turbines to meet these expectations. I too might have tried a Wren or a JetCat turbine, but the fact is that im not a wealthy person nor can I afford spending $2500+ on a turbine package.

As far as Wren refusing to sell and item to a potential customer is just BAD sales practice and very unethical to devuldge information on customers and information of who is tring to purchase what. Furthermore, the comparison of the performance of a Rolex to a digital Timex is just rediculus (a Timex digital gives much much greater accuracy than a mechanical movement of any kind).

dw_crash

My Feedback: (6)

J_rc_HELIMAN,

Well said. Lets get back to the main thread. I have heard these thoughts, offline, about who owns what. And, who fixes or services what. Your right, my JJ1400 works when I ask it too. So go fly and have fun....The rest is meaningless. It like arguing Thunder Tiger over OS. Both do the job ( I own both) and I have fun with both. That's what a HOBBY is for.

DW_Crash

josecilurzo

http://www.rcuniverse.com/forum/m_8544893/tm.htm

no questions!!!! no answers!!!!![sm=thumbs_down.gif]

jose [8D]

Woketman

My Feedback: (6)

More like arguing about a 1973 Fox .15 with no ball bearings and a modern OS four stroke!!! Nahhhhh! The difference in quality, from what I have seen, is A LOT bigger than that when you are talking JJ & Wren!!!

Gordon Mc

My Feedback: (11)

Yes - you should be able to buy spares from the Turkish JetJoe agent ... according to http://www.jetjoe.com/htm.php?nowmenuid=9648 he is:

Turkey:
Mr. Murat Bukey and Cumhur Guvenc

Sehitler Cad 18/3 Alsancak Izmir 35230, Turkey

Tel: +90 532 615 07 33

Web: www.gjet.net

Email: [email protected]

Hope that helps !

Gordon

akpepp

I wasn't bashing the JJ... I have the JJ1400. The Rolex comment was pointing out that a rolex is expensive...but performs the same purpose as the less expensive Timex.

HKruisman

Hi Guys,

I have a JJ1400 which is still under guaranty but i want to improve it (make it usable ) Photo's can be found here : http://sharepoint.ccme.nl/Fotos/Modelbouw/JetJoe%201400

What i did / am going to do:
- Fix the fuel ring. It does not burn that well. 2 needles burn very badly and 1 does not burn at all! (FIXED)
- Replace bearings. The rear GRW is ok but the front is imitation. Both will be replaced by high quality bearings (should be even better then grw) (ORDERED)
- Alter the sticks. Good sticks have "dents" in it to slow the fuel flow and vaporise better. (TODO)

The fuel ring wasn't that much of a problem. I heated the ring to melt the solder and than put a compressor on it to clear the path. Burns much better now. 1 stick burns a bit less but should be enough for now. Egt should drop a bit now.
The front bearing does not run that nice as the rear grw bearing. It had a bit more drag and better bearings should help to reduce the egt a bit.
Sticks with dents should help for better accelleration and better mixing of air and fuel. It also should bring the flame more to the front of the cc which helps to save the ngv.

Other valves are needed because the supplied valves sometimes hang. A small tick on them closes them correctly. For testing now it is ok. Start motor cluch is very very bad. No system to lock in place. It has also touched the compressor nut while running.

myring

What bearings you ordered are better than GRW bearings? I'm interesting in it.

HKruisman

Hi,

I ordered a pair of these : http://jmprecision.co.uk/shopping/pg...&=SID#MOREINFO

Price is awsome and the say 172K should be ok. I will test them against the stock bearings.

I did a test run with the modified CC and left the cone off to get a better look inside the engine. I could not believe the egt. Only 440 at idle. very low during startup also. Engine behaved normal. I heard a little rubbing so i did not go above 70K. Egt rose to 480 max! Does the cone have so much to do with the egt or is it my modification that lowered the egt? Maybe the cone can be altered to lower the egt......

Tonight i run again with cone (and without rubbing i hope). I could not see any rubbing after the last run.....