Leo518

wish your flight successful.



Leo

AndyAndrews

man that is a clean install. Can you guys post some videos?

Dave Wilshere

After a busy period and just having returned from our National Championships, I decided to start putting together a demo Cougar with the idea of having it ready for Jet Power.
I'm using JR radio/servos all round, JetCat P120SX, probably UP Valves.
Tailplane tonight, JR 3401's fit easily, one mount needed a small packer to stop the servo moving forward and backwards. I changed the linkage to a 3mm clevis on the servo end.

Dw

Dave Wilshere

Another evening and nearly completed one wing. Went through my usual process of running in the servos, JR8401 on Aileron and 8511 on Flap. Both servos are a snug fit, but go without any wood trimming.

Dw

schroedm

My Feedback: (1)

Dave,

What do you use to 'run in' your servos?

Also, I assume those horns are a different material to the Comp-ARF ones seeing as you've used a ball link on one side??

M

Dave Wilshere

Mark

Graupner Nr. 764.

Yes, they are solid and don't flex at all.

Got the flap horn in too, needed an extension on the front part of the flap horn where it inserts into the flap as I moved the horn position back a little to get better geometry when the flaps are down...as they are bottom hinged. This meant I missed part of the wood block. The horn extension goes to the top skin of the flap.

Dw

Dave Wilshere

Finished the second wing having had a night off catching up with work missed while entertaining JetCat's big boss for a day...the next 12 months are going to be great [8D]

If like me you don't have a scrol saw in the workshop (mines at work!) this is a quick method of making a notch with minimum effort...2 minutes start to finish

Dw

cavandish

apologies for digging up an old thread, but I am sure someone can help.
I am in the process of ordering a der jet couger & would like to get my servos on the way. please advise the total number of servos required assuming that I am using the supplied air valves, and the recomended torque ?
thanks
John

Dave Wilshere

John

Thanks for digging it out! I must finish and fly this...
You need 15mm-4.5kg plus servos for the elevators. I used JR 3401's I think!
Standard size 8411 case size servos are easiest to fit, you need 2 x Ail, 2 x wing Flap, 2 x Fuselage Flap, 1 x Rudder, 1 x nose steering. If using the stock valves you need 4 mini JR 385 size servos,
I would use 9-15kg servos on all the main controls.
I have a feeling there is detail earlier in this thread. Yes! 11kg ailerons and 15kg Flaps on mine

Regards

Dave

cavandish

Thanks for your reply Dave
assuming that the elevators use 2 servos, that adds up to 14 servos ?
I would like to fly the plane with my nine channel JR, assuming that I drop the fuse flaps and use programable digitals, is this possible ?
please help me understand why 4 servos are used for the air valves and what the 4 functions are ? is it possible that the aircontrol system would use less channels with an electronic multi function valve ?
thanks for your patience !

tow

Since I too am in the process of getting my paws on a DJ Cougar just thought I chime in!
Christmas in June maybe........

Dave Wilshere

You can get away with 9, but will need matchboxes. The Valves supplied are single use valves, Gear, Gear doors, Arrester Hook and brakes. You can also add a sliding canopy!

Yes, use a UP2 and UP4 valve (one channel only needed to do gear and all doors) Matchbox four Flaps.

Dave

cavandish

oops

cavandish

Come on Dave, I would love to see some more of you build as my cougar is on route from Asia.
I am not going to have my tail hook operating, does the air ram designated for this purpose have enough travel to operate the hatch ?
has anyone got the hatch sliding back via air, and how much hassle was it to do ?

tow

Mee too!

BluFox

My Feedback: (10)

Cavandish:

We have complete details on the sliding hatch for Cougar as well as complete build manual with excellent detailed color pictures.

Regards,
Eric Clapp
DerJet USA

Dave Wilshere

Sorry, been in Germany for four days at an amazing venue and contest, the Formation Cup, the Cougar is No 2 after my P-80SE Ultra Flash, so should be back on it by the months end. We were going to use a UP ram for the canopy, from memory the canopy cannot go all the way back so the hook ram is way too long, but with air you can have an over long ram without a problem.

Regards

Dave

cavandish

Buy yourself a power file, I use it more than a Dremel.

see here

http://www.google.co.nz/url?sa=t&sou...DxIKasngStQfmQ

tow

Where can I get that.........details for the sliding canopy I mean.......?

tow

Hi! Looking at your photos, what is the distance from turbine tailcone to pipe bellmouth? It looks far off, but maybe just the camera`s fault?
Regards

Dave Wilshere

Looks about right 20-25mm

Dw

tow

OKI Thanks!
On another pipe I have is suggested 30mm so I guess you`re right!
Regards

Dave Wilshere

It comes down to the pipe diameter. larger-smaller gap, smaller-larger. Most 120 pipes are 75-95mm dia. Obviously overall pipe length will affect dia too!
Overall affect on gap is temperature and thrust, but most engines are easy going. I'd always air slightly larger gap, so 25-30 would work for me too.

Dw

tow

Thanks for the info. Judging from the photographs the gap seemed awfully large wich made me wonder.... An idea to put some heat-insulating stuff in between maybe, to shield the fuselage - besides there is some servoes down there too... Looks like some of the guys did just that.
Just started some assembling on the kit, so there`s gonna be awhile..........

Dave Wilshere

Back on this again before attacking the Mig and Eurofighter.
Decided to paint the nose structure, so two coats of ZAP 40, rub down and prime before painting with a red car paint just before I left the office.
Working on the fuselage flaps, my moulding has left the hinge a bit stiff, so I'm working at that to free it off.

Dw