L39/Wren 44 Pics and video
08-07-2015, 07:00 AM
#4251
we have build it like this
http://www.jetsweden.se/forum/e107_p...wtopic.php?767
retracs is functional air up/ spring down.
Tomas
http://www.jetsweden.se/forum/e107_p...wtopic.php?767
retracs is functional air up/ spring down.
Tomas
08-08-2015, 02:56 AM
#4252
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Nice... Love the CNC cutouts. Do you have any templates?
Re retracts, how do u control the speed down? Since they are spring down.. Regulator on exhaust?
Love the build. Thanks for the heads up.
Re retracts, how do u control the speed down? Since they are spring down.. Regulator on exhaust?
Love the build. Thanks for the heads up.
08-08-2015, 05:28 AM
#4253
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Nice... Love the CNC cutouts. Do you have any templates?
Re retracts, how do u control the speed down? Since they are spring down.. Regulator on exhaust?
Love the build. Thanks for the heads up.
Re retracts, how do u control the speed down? Since they are spring down.. Regulator on exhaust?
Love the build. Thanks for the heads up.
10-14-2015, 03:01 AM
#4254
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Thanks to Yann, engine mounts and servo mounts... Settled 
Powerbox Gemini 2 power switch for 2s Lipos,
I am still at a loss what go use for the control horns.
Gabriel 2mm ball link - 15mm horns??
https://www.lindinger.at/en/rcelectr...arm-14mm-hitec
https://www.lindinger.at/en/airplane...horn-5-15mm-m2
Powerbox Gemini 2 power switch for 2s Lipos,
I am still at a loss what go use for the control horns.
Gabriel 2mm ball link - 15mm horns??
https://www.lindinger.at/en/rcelectr...arm-14mm-hitec
https://www.lindinger.at/en/airplane...horn-5-15mm-m2
12-01-2015, 10:28 AM
#4256
Join Date: Feb 2015
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OK... Update. Help needed anyways.
Ar12120 rx, Gabriel 10mm arms.
Last on the shopping list : Servos.
HS5085 Flaps and Aileron.x4
HS5125 rudder and elevators.x3
Nosewheel Micro Digital.
OR- But I think they won't fit as they are too small.
MKS DS93 Flaps/Ailerons X4
MKS DS6125 Minis Rudder/Elevators x3
MkS standard digital for NWS.
The Hitecs put me off because of the plastic gear, even though it is the small gear, so the load is the least on the drive train. But....
Anyone try them? Can't find a decent review on them!!
The MKS fit the spec, but they seem way to small to fit in the supplied wing servo holders.
Anyone has a spare MKS to try the fit?
Am stuck!
Starting to design the equipment tray. Pioppo wood to be used with 3mm aluminium standoffs for the second layer tray.
Thanks.
George
Ar12120 rx, Gabriel 10mm arms.
Last on the shopping list : Servos.
HS5085 Flaps and Aileron.x4
HS5125 rudder and elevators.x3
Nosewheel Micro Digital.
OR- But I think they won't fit as they are too small.
MKS DS93 Flaps/Ailerons X4
MKS DS6125 Minis Rudder/Elevators x3
MkS standard digital for NWS.
The Hitecs put me off because of the plastic gear, even though it is the small gear, so the load is the least on the drive train. But....
Anyone try them? Can't find a decent review on them!!
The MKS fit the spec, but they seem way to small to fit in the supplied wing servo holders.
Anyone has a spare MKS to try the fit?
Am stuck!
Starting to design the equipment tray. Pioppo wood to be used with 3mm aluminium standoffs for the second layer tray.
Thanks.
George
12-05-2015, 04:03 AM
#4258
I used savox 1250 mg servos which are from a crashed bobcat. Cut all of the things under plate, made the plastic surface irregular, put double sided adhesive bant and thin wood blocks; glued servo to place with aeroepoxy. 
I used balsa (1 cm) for tray; put 2s lipo battery, ubec and 150 grams lead (cg issue) front. Dry weight is 4750 grams.
I used balsa (1 cm) for tray; put 2s lipo battery, ubec and 150 grams lead (cg issue) front. Dry weight is 4750 grams.
12-05-2015, 04:49 AM
#4259
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Ah! Thanks is also a good solution!! Avoids the micro servo issue.
I see you are using a hopper tank....single tank? Or the Paul twin set up?
Had in mind of a CAT from gbr jets.
Thanks for the servo idea...
I see you are using a hopper tank....single tank? Or the Paul twin set up?
Had in mind of a CAT from gbr jets.
Thanks for the servo idea...
02-03-2016, 01:59 PM
#4272
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If I don't finish mine this winter and be ready for some jet antics come May 24 weekend, I will be very ashamed.. 
I'll shoot some pics of the motor mount arrangement and tailpipe mounting, those are done at least. The nosewheel cutout is on an angle to the centerline of the fuselage (sloppy!) so I will likely fill that in and redo. Retracts mounted, aileron/flap servos on plates. Trying to do concealed rudder and elevator linkages, think I have it all worked out (couldn't take the easy route now could I..?). So it is all about linkages and plumbing for a while.
I'll shoot some pics of the motor mount arrangement and tailpipe mounting, those are done at least. The nosewheel cutout is on an angle to the centerline of the fuselage (sloppy!) so I will likely fill that in and redo. Retracts mounted, aileron/flap servos on plates. Trying to do concealed rudder and elevator linkages, think I have it all worked out (couldn't take the easy route now could I..?). So it is all about linkages and plumbing for a while.
09-21-2016, 06:01 AM
#4273
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I know is a old thread, but we had a good surprise last weekend.
I and a friend bought a L39 with a wren that never worked well years ago, this wasnt caused by the turbine quality itself, but because it simply didnt worked well at our field wich is located 3.000 feet above sea level. So off with the wren and we installed a P60, with reduced rpms.. this kind of worked, but the airplane felt very heavy and flight times were extremely short.. so as this didnt worked as well as we liked this plane got gathering dust for years.
However we recently heard about people having success with KT engines, and we decided to give a try on the 45.. Last saturday we tested the combo, and it was great. Cruise flight at half throttle and plenty of vertical at full throttle like a jet should do. Fuel consumption is low, and the plane feels well, like a average jet. Best of all the turbine is one of the few that didnt required tweaking or fiddling. Just fuel and go. I am impressed with this turbine and we are finally happy with this combo.
Hope all my long time friends here are doing well. Best regards, Enrique.
I and a friend bought a L39 with a wren that never worked well years ago, this wasnt caused by the turbine quality itself, but because it simply didnt worked well at our field wich is located 3.000 feet above sea level. So off with the wren and we installed a P60, with reduced rpms.. this kind of worked, but the airplane felt very heavy and flight times were extremely short.. so as this didnt worked as well as we liked this plane got gathering dust for years.
However we recently heard about people having success with KT engines, and we decided to give a try on the 45.. Last saturday we tested the combo, and it was great. Cruise flight at half throttle and plenty of vertical at full throttle like a jet should do. Fuel consumption is low, and the plane feels well, like a average jet. Best of all the turbine is one of the few that didnt required tweaking or fiddling. Just fuel and go. I am impressed with this turbine and we are finally happy with this combo.
Hope all my long time friends here are doing well. Best regards, Enrique.
Last edited by erbroens; 09-21-2016 at 06:04 AM.
09-21-2016, 06:30 AM
#4275
Join Date: Nov 2003
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We kind of resisted the urge to fly this plane with electric power. mostly because we have some electric planes and even if the prop jobs are ok, is very difficult to find a good edf system that sounds more or less realistic.
Also as this turbine uses so little fuel, and is kerostart the amount of gear needed to fly it is smaller than a EDF charging station and extra batts. Anyway, glad you find a solution also.
Also as this turbine uses so little fuel, and is kerostart the amount of gear needed to fly it is smaller than a EDF charging station and extra batts. Anyway, glad you find a solution also.