Dansy

My Feedback: (53)

I have never measured the festo fitting, but that’s what I used in the one I build with a 210 as well…I will check once I’m home

dccatl

My Feedback: (1)

Hermann,

I ended up ordering 8mm OD (6mm ID) fittings from Ultimate Jets vent fitting , tank stopper you can see them installed here: Carf rebel pro, these might be overkill, but they've worked great with my K210 for about 75 flights.

David

h+r+h

Thank you David and Dansi

essyou35

My Feedback: (11)

Still licking my wounds from this loss, but getting over it. I still have 6 jets left 5 of which havent flown yet so I cant give up. Im really considering a bolt as well.

Oh here is what an 11K burn spot looks like. The fire from the jet is where those dark spots are and it was quick but the grass was so dry it just kept slowly burning in all directions. My turbine has no fire damage so I think the lipos are what went up. However the engine may be totaled. That little leg thing going of to your left is also from the fire, it just kept going and going! 9 fire extinguishers didnt stop it. So fire department came. They were super cool about it and told me this is a burn area every spring. But of course peanut gallery is still talking about it.

Fagox

Had my 16th. flight this week, this bird lands like a 747!



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Skunkwrks

So where's the CG position on the wing tube?
It does fly very nice, you can get it to wheelie on the mains why slowing down . They are great flying bird.

Fagox

Thank you Skunkwrks CG as is suggested in the manual with empty main tank and full header tank better to be on the Front Edge of Wing Tube! But very forgiving CG, you can tolerate CG about 1.5" before or after of the Edge of Wing Tube!

smcharg

My Feedback: (1)

Interesting. I thought the Pro and the Max were the same for CG as the Max is back of wing tube up to 20mm aft of that. Obviously, it flies well as we see in your video. I was just surprised to see the manual now say at the front of the tube.

Fagox

Thank you, you are correct on CG, having said that, All four Rebels are going easy on CG, so unless you are using an unusual heavy turbine and pipe, you will be fine.


Turbine Behotec 220N
Radio Graupner MZ-32 with two double GR-24 receivers.
All Servos except Rudder and steering are Futaba A700 (75kg)
x6 MKS -X5 (on rudder and steering)x2
Powerbox Mercury GPS III
Electron GS-200 Controller
and ER-50 Retracts
Dry Weight including batteries: 36.5 Pounds.
Hemet "Model Master RC Field", California

Kenrico

when I built my Pro back of the tube is what Carf said. I was at 10mm behind that and I recently removed a few more oz of lead so I should be just a tad more now, flys perfect.

Skunkwrks

Total agree I'm at 10 mm forward of the back edge of the wing tube .
The thrid page of the Rebel manual

Kenrico

Nose heavy then..

Fagox

I do agree but It is the matter of the preferences the was you like to stick, I like a little nose heavy on this jet, this is not a 3D jet, anyway as the manual indicates, you have about 20mm freedom choosing the CG forward or back ward of the tube edge.

Skunkwrks

I guess on asphalt the nose doesn't bounce after landing , on grass field the nose is bouncing after landing with 1.5-2 liter left from the six liter tank.

Fagox

I thought on the grass bouncing is less!

Dave Wilshere

Depends on the grass surface! Generally landing on grass is more forgiving, but nose bounce will be down to how smooth the surface is.

Rebel balance is a factor of fuel on board. All the fuel is forward of the balance, so without a measured quantity all this talk is just wearing out your fingers tapping away!

Rear of the wing tube with landing fuel left (no top hatch on) is a good starting point, then adjust for your preference.

smcharg

My Feedback: (1)

Fagox to be clear, I was NOT disagreeing with your CG position. It was just interesting to me. By your video, your CG is wonderful...for you. The CG range on the Rebels is amazing and I agree with Dave and this discussion came up in my MAX thread. I suggested doing CG with landing fuel and caught a bunch of crap for it haha. But, to be fair, you have to look at the possibilities, not just the probabilities and there is a possibility that one could run the tanks dry which would be worst case and the most aft CG. Therefore, a check there is still a great idea. If one were to find the AC (aerodynamic center) of this aircraft, I think you find that our SM (static margin) is probably around 6-10% at the center of the tube which is why you can go 20mm in front or behind the back of the tube. The bounce in the nose is purely due to the position of the mains in relation to the CG and nothing to do with how it behaves in the air. I believe Andreas purposefully put the mains in that position to allow the aircraft to rotate effortlessly. You've done a great job with your Rebel.

Jan Roskam says place the mains 15 degrees aft of the CG. I'd say it's spot on.

Fagox

Well Said!

Dave Wilshere

My balance is safe with no fuel…tested that. It was just an easy reference as we hook our fingers under the turbine opening side lips and lift. Hatch has to be off. Easy to eye ball down to the rear of the tube.
People fixate on balance, just go and fly with it close to the spar, if you know what you want from a model you will adjust to suit. Most just fly how it is anyway if it does not bite them! It’s why people have flown CARF Vipers so nose heavy for so long…

Skunkwrks

Scott, I would agree with the nose bouncing , my field is very sparse with patches of dirt and grass. We have to get the CG with fuel still in the tank, what would be left after say 9:30 of flying? When and if I burn the whole amount I would still would be in the CG window just probably a couple of mm behind the rear tube. The way mine is balanced it's the most forgiving plane I have flown since my racing days three decades ago. I have a couple 4mm of elevator down trim mix in with takeoff flaps, and it just rotates effortlessly off the runway, it seems to be in a sweet spot of the Rebels CG. Have installed a CMjets smoke tank and will recheck the CG. It's installed been the wing tube and should only marginally move the CG back.

Racer686

I need to repair one of the keyholes (putting the front and rear halves together). The backing that was epoxied on, popped off, and you can see the hairline crack in the fuse there. How would you recommend repairing the area to be sure that it is sturdy for flight? What sucks is that this damage was done by the shipping company, the box was half ripped apart and luckily this is the only damage.

sewbusy

Mine did not have that kind of damage....but If I were you, I would only glue behind the lip with a little carbon fiber strip or fiberglass if you don't have the C/F. Since the locator holes are not screwed in all the way, there is no direct load on that bolt.....It's only for locating the back half to slide downwards.
Wayne

Dansy

My Feedback: (53)

I would Hysol it back On, once dry apply a strip of carbon Fiber…covering the crack from behind

smcharg

My Feedback: (1)

My Max did the exact same thing during the build process. I believe there are a few pictures in my thread. Clean the surface of the backing and sand around on the inside of the keyhole and hysol again. No problems since.

Skunkwrks

I should check mine for cracks now you guys have mentioned it.

Just checked and no sign of movement or crack in the fillets should put this once the checklist for when assembling and disassembling the plane.

Scott and Dansy are correct just some Hysol in and around the bracket and you're golden.