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        Help! About to pull the trigger on a SMALL turbine ,, Jet joe junior

#1 littlepiston Jan 10, 2013 09:14 PM

About to pull the trigger on a SMALL turbine ,, Jet joe junior
 
So i have been saving up for a bit and i have the funds to order a JJJ but would like to know what you guys think, should i get a P20 or a Kolibri??:confused:
If i get the kolibri it would be the T25.
What would be the advantages and disadvantages for all three?

#2 Boomerang1 Jan 10, 2013 11:48 PM

If you want an engine which will run properly straight out of the box forget about the Jet Joe.
The only people who can seem to get these running properly are those with a great deal of turbine experience and access to precision balancing equipment and/or friends with those skills and equipment as well as a lot of time to spend fiddling.

I have friends with both the Kolibri & the P-20, both are top quality engines ready to operate properly with a minimum of fuss. The P-20 is in a Habu 32, the Kolibri has been in a foam Multiplex Twinjet & a Savex L-39 albatros.

The Kolibri comes from a one man band, Martin Lambert, who is a real craftsman & perfectionist but can be hard to get hold of for sales or service.

Jetcat, of course, is the biggest manufacturer of turbines in the world although they seem to get snowed under with service/repairs & this can lead to delays getting an engine fixed.

I don't own any of these particular engines so I cannot speak first hand, just on friend's experiences & owners posts on the forums.

If cost is a factor the bigger engines may be cheaper to buy, the Wren Jubilee & Kingtech K-80 are probably the price leaders at this point in time, the Jetcat P-80 also seems to be priced low as well.

However, being bigger engines, the models & accessories to suit them may cost you more in the long run.

Hope that's a help. - John.

#3 henke Jan 11, 2013 12:23 AM

I never ran a jetjoe junior my self. What I know is that is it a copy of an early Lambert Kolibri (old T15). For me performance is the most important thing. I own three Kolibris today, I do not se them as expensive as they work very well. If I would have bought any other turbine which did not work or did not perform as it's supposed to I would see it as expensive even if $2000 less then the working unit.

P20 now seem to start and run well and put out about the thrust it's should. I think Jetcat meassures at 0C and by 0C it does the promised 24N. The older P20SE however did not, I've seen one run at just slightly above 2kg of thrust in 20C ambient temp. For the Kolibri check my videos and judge your self, reality beats fiction every time :)

http://www.youtube.com/henke2

P20SX vs Kolibri T25-HP (9 min 9 sec)



Kolibri 270grams, Jetcat P20SX 272grams(without cables)
http://imageshack.us/a/img534/1264/2...1zed201211.jpg

Installed weight of the P20 is 150grams more.
http://www.jetsweden.se/forum/e107_f...0_imag0295.jpg

http://www.jetsweden.se/forum/e107_f...0_imag0298.jpg

P20SX, EGT probe too far in to get proper reading.
http://www.jetsweden.se/forum/e107_f...0_imag0307.jpg

Kolibri T25
http://www.jetsweden.se/forum/e107_f...0_imag0308.jpg

Jetjoe junior
http://img707.imageshack.us/img707/7582/p1010125hu.jpg

Jetcat P20
http://images.rcuniverse.com/forum/u...56/Tq48645.jpg

Lambert Kolibri(old T15)
http://homepage2.nifty.com/tachino/turbin/t32-001.jpeg

Lamberts new laser welded combustor
http://imageshack.us/a/img600/1671/bild2if.jpg


I have NOT tested the junior my self only found pictures on the web. I want to test one but it just has not happend yet...

Jetjoe junior idle
http://images.rcuniverse.com/forum/u...60/Mk26664.jpg

Jetjoe junior full power, check the EGT(!)
http://images.rcuniverse.com/forum/u...73/Yw68734.jpg

Jetjoe junior with melted turbine nut
http://images.rcuniverse.com/forum/u...73/Fd91065.jpg

#4 littlepiston Jan 11, 2013 12:53 AM

keep them coming guys, i own a rabbit,wren SS,wren 44 so im not new to turbines. I want a smaller jet (well i have a hand full of them) and would like to own a smaller turbine. All at addieshobbys has been building these JJJ for a wile now and is said to have figured it out and has had good results.

#5 henke Jan 11, 2013 06:21 AM

Quote:

Originally Posted by littlepiston (Post 23778906)
All at addieshobbys has been building these JJJ for a wile now and is said to have figured it out and has had good results.

If you have a dealer near by where you can go for support with various issues you would probably do fine with any brand of engine. I guess people choose the P20 as their dealer feel more comfortable with jetcat as a company then Lambert (which by the way grown to a 2man show now)

Thats why you should read alot to get the whole picture. I try to present technical info as true as I can but other things matter too.

#6 Dr Honda Jan 11, 2013 07:04 AM

Little Piston:

Unfortunately what Henke is saying is correct. The JJJ has problems with it's quality, and design. The only way I would buy a JJJ is if I bought it from "Konbby1". He's the tech at Ausi-Jets. He hand builds them, and they run very well after he's done. The 4 big things he will do is...

1) Balance. He gets them better than 0.3mg/mm. That's about 10x better than factory.
2) Opens/shortens the tail cone so they run cooler.
3) cuts a few mm of the front of the compressor, and shaft. Basically, at 230,000 RPM... there was enough overhang, that it was causing the shaft to flex, and it was killing the bearings.
4) Changes the bearing pre-load.


The final issue is that they only make about 4 Lbs of thrust, and even with his mods... only expect 15 to 17 hr's on the bearings. If you buy a JJJ from a regular dealer... they may only get a few starts before they fail.


Just an FYI... KingTech is supposed to release a "K-35" this summer. Personally... I would hold out for that. Barry said it would be right around $2k.

#7 henke Jan 11, 2013 08:17 AM

Quote:

Originally Posted by Dr Honda (Post 23780076)
Just an FYI... KingTech is supposed to release a "K-35" this summer. Personally... I would hold out for that. Barry said it would be right around $2k.

Also Jets munt is preparing an engine of P20 size, but not available any time soon. Also when they pop up on the market I would wait a year for them to make a mk2 with bug fixes. As Jetcat did with their SE to SX improvements. (I was told by Jetcentral that their nono turbine "flea" is canceled)

However waiting for something that might come will probably end up making you grounded for the whole summer.

There's also a Super Kolibri in the works with new internal components where 7lb of thrust for production engines are possible and close to 8lb for selected engines. Martin increased the rpm to reach the same EGT as the P20 in my video and recorded 8.4lb of thrust in his test cell of normal room temprature. He says that is too hot for other then testing though. But not available yet and no price nor name decided yet.

#8 henke Jan 11, 2013 08:23 AM

and... to be as informative as possible... There are one guy modifying the Jetjoe junior to make 2.6kg of thrust. He puts in a larger compressor, alters the combustor and remakes the lousy fuel injector ring. But when finnished changing components that is not up to the job I bet a Kolibri or P20 would have been a chaper choice.

This guy is really good and have designed his own turbine this size too, so nothing easy to do, even if possible.

:)


Jetjoe junior pic I found on the web showing the fuel injectors.
http://img96.imageshack.us/img96/6155/25779508.jpg

#9 littlepiston Jan 11, 2013 10:36 AM

So it seems that in my case,my only option is the Jet Joe Junior. The Kolibri and the p20 are not far from my reach but they both have negatives.
The Kolibri has almost no support. The p20 is as much as the kolibri so if I was to speng that kinda money I would rather go with the kolibri.
The Jet Joe Junior on the other had is serviceable here in the states,it also has about the same thrust as the t15 and its smaller than the p 20.
From the videos that I've seen here, it seems to me that the p20 is sruggling to put out the thrust it's was designed for?.
I would like to see if anyone else can post that has a good running Jet Joe Junior from ausy jet aka I believe Addie's hobbies.

#10 henke Jan 11, 2013 11:24 AM

Quote:

Originally Posted by littlepiston (Post 23781677)
The Kolibri has almost no support.

First, remember I only own Kolibris, but I still try to be as informative as possible.

Lambert seldom answers emails but almost always answer the phone, he speaks great english. You also have the forums.

As for Jetjoe or P20 I do not know more then gossip.

To compare the engines you need to compare the T15(4.2lb thrust in room temprature) with the P20 as I think those would power the same plane with the same performance, as the Kolibri airplane will be lighter. The T20(5.3lb) would do even better and the T25(6.2lb typical) is in another leuge.

If you feel you have great support of the JJJR it might be a good option for you. even if it likely "only" puts out 2.8lb it will still power a funjet very well, or any 70mm EDF airframe out there.

Search youtube for videos and you will find alot of each engine. Check my vids as linked in my first post.

Also as for the Jets munt M35 or the Kingtech K35 I think those will be great engines but most likely heavier then both Kolibri and P20 so not really comparable, specially not against the T25 Kolibri. In this nano class weight means alot, engine weight is not all, but the installed weight incl lead to ballance.

For me it doesn't matter which one you choose, but if on a limited budget I would go for the Kolibri T15 airstarted version. I think it will be cheaper in the long run.

#11 Dr Honda Jan 11, 2013 11:48 AM

Henke: there is ZERO support for Kolibri's in the USA. AND... for some reason, they are crazy expensive here. The last USA price I saw was about $3500 for a 25. That's about $1000 more than a P-20.

Littlepiston: The last time I talked with Bret... a hand built JJJ from Ausi-Jets was $1650 shipped to the USA.

http://www.ausjets.com/index.php?pag...emart&Itemid=3

#12 littlepiston Jan 11, 2013 12:52 PM

Quote:

Originally Posted by Dr Honda (Post 23782325)
Henke: there is ZERO support for Kolibri's in the USA. AND... for some reason, they are crazy expensive here. The last USA price I saw was about $3500 for a 25. That's about $1000 more than a P-20.

Littlepiston: The last time I talked with Bret... a hand build JJJ from Ausi-Jets was $1650 shipped to the USA.

http://www.ausjets.com/index.php?pag...emart&Itemid=3



I've seen the price go down to 1500

#13 littlepiston Jan 11, 2013 01:01 PM

Quote:

Originally Posted by henke (Post 23782107)
For me it doesn't matter which one you choose, but if on a limited budget I would go for the Kolibri T15 airstarted version. I think it will be cheaper in the long run.

Are these t15 readily available? Can you get your hands on one today?im trying to find out what this would cost to ship to the US.
What would be the total and which place to order it from?

#14 henke Jan 11, 2013 01:07 PM

Quote:

Originally Posted by littlepiston (Post 23783005)
Are these t15 readily available? Can you get your hands on one today?im trying to find out what this would cost to ship to the US.
What would be the total and which place to order it from?

http://www.lambert-modellturbinen.de/

They are 1850 incl 20% VAT. Export that would be ~$1900 + shipping. If you have no luck calling Martin you can always try emailing amir@hab.se

#15 henke Jan 11, 2013 01:13 PM

Quote:

Originally Posted by Dr Honda (Post 23782325)
Henke: there is ZERO support for Kolibri's in the USA. AND... for some reason, they are crazy expensive here.

I've seen the prices on sincityjets.com He too needs to update his hompage as he lists the old T32(the older version of T15 which Jetjoe copied)

I have no clue if he has any support. Anyway if not selling the engine I guess it's limited. If you buy from HAB you have full support, but they are located in Sweden which still doen't make it as comfortable.

Ok, I'll try to not push for anything you don't feel comfortable with, I just try to explain the engineering diffrences and why I choose engine the way I did.


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