No sorry for being quiet, I am continueing as much as possible. I have promised my son to have it airborne on Saturday 27 October. More photos very soon...
Everyone should check the retract units, as mine were not secured with blue thread lock and some bolts were even loose !!! Also, lubricate the units very well (at the outside) with some drops of oil on the metal tracks, it made a difference of safely operating them at minimal 5 bars instead of minimal 8 bars. Use also at least one additional (Robart) air restrictor at the (air outlet) side of the air cylinders when the gear comes down, the action might be very violent otherwise and with such weight of the legs might damage the wing bulkheads. It is incredible how many air restrictors I have used so far but now the whole operation is exactly like how I want it, slow like hydraulics but very reliable and scale.
Except for the flaps (Futaba S3305 - 2 pcs), I will use the new brushlessFutaba BLS451. (5 pcs) with Weatronic receiver and 2 Lipos 4100 MAh/2 cells for JetCat ECU and RX, plus back-up Lipo 1350 MAh/2 cell.
Yes, the fit of the kit is excellent, gets together quickly, I can focus entirely on fine-tuning during construction.
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Joined: 6/9/2005 From: Cardiff, UNITED KINGDOM Status: offline
Nicolas, Thank you for the info, please keep the build details comming. Re weathering I have started a new thread and have had some really good replies. Take a look at Tom Pierce's site it is full usefull information .
Here are some more photos of the pneumatics and fuel plumbing, completed now. (I am not always using the conventional way, I know .) Tank capacity is now almost 3.5 liters (92 oz). Everything mounted on the RX board will be in "modular" style : pneumatic module, ECU module, gyro module,... On one of the photos is the CNC custom made pneumatic module. I still prefer mechanical valves as this is easy to operate manually in the workshop. The proportional wheel brakes is a Jettronic single valve. The belly air spoiler is operated with an old BVM air cylinder (the alu arm must be extended for the long stroke of this cylinder). I was really surprised how much torque and holding power such system has, it surely will not collapse in flight.
For door hinges, I used the large alu Robart #350 on main doors with Robart air cylinders, and nose door is Trim Aircraft offset door hinges and BVM air cylinder.
Tonight, I'll study the rudder again. That's a bottleneck ! I have tried the link system as per the plan and it is NOT SAFE. Too much slop and no torque enough to prevent eventual high speed flutter. I installed the stainless steel pin on a metal servo arm and digital JR 8455,.... not good enough. I have two alternatives in mind, to be tested tonight.
5 air pressure tanks -two in the nose and three next to the air inlet ducts- , 1 large propane gas tank... hopefully I can fly all afternoon with one single charge done at home )
I forgot to show my experiment with a "secret weapon"... a test with three AVCS gyros... one on each jet axis !
I am lacking free channels on my Futaba 9ZAP for the setting the sensitivity of each one separately, but I plan to connect them one by one and then program the fix max sensitivity in the Weatronic receiver. Superb software, by the way ! Unbelievable programming possibilities, such as setting the proportional wheel brake on the switch channel of the ECU but controlled by giving down elevator and only when the wheels are down, sequencing doors,... If you program it smart, combined with the possibilities of your transmitter (mixers and different flight conditions), you can add a lot of functions in the existing number of channels of your transmitter... Can't wait to put my wildest ideas into it !
Christos, don't forget to bring me your P-160 and RX on Saturday, please !
OK, here come the requested photo details of the kit. Overall, everything is excellent done, fit of the parts is perfect. Panel lines are in the moulds. Seams are visible -but note these photos are taken VERY closeby, some of them 2 inches away -. Doors, flaps,... everything is pre-moulded and painted in the moulds. Paint looks a bit too glossy, but consider it as a good base for a weathering job. Only bad comment I have is the lack of a manual and the plan not showing some of the most important details. I do not need a plan to see how big it is or where the bulkheads are (since these are pre-installed anyway), but I need it to see where hinge lines are, and how and where to cut and install.
Photos below.
Enjoy.
PS. Don't mind the dust everywhere... that's my fault, not the manufacturers'. PS2. Some pics are a bit blurred as I preferred not to use a photo flash on such close distance ; it's just a simple pocket digital camera...
Nicolas.
< Message edited by SpiderJets -- 10/12/2007 9:03:48 AM >
Pre-installed hatch latches and hatch pins, perfect fit, no more work to be done here.... The one for the canopy is inside the fuselage and has an (pre-installed) handy extension pull wire and finger loop to pull it open from the turbine bay hatch... Nice detail.
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All Forums >> RC Airplanes >> RC Jets >> RE: What do you think about JETLEGEND L39? 
RE: What do you think about JETLEGEND L39? - 
but now the whole operation is exactly like how I want it, slow like hydraulics but very reliable and scale. 
