New OXAI CITRIN by Wolfgang and Roland Matt
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RE: New OXAI CITRIN by Wolfgang and Roland Matt
Another photo of Citrine with a brocken nose, happened on the world cup in a Chech Haven,on line 45 upwards a motor fly out from fuse and flew away,motorwas without back support Motor is Q-80
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RE: New OXAI CITRIN by Wolfgang and Roland Matt
ORIGINAL: andreyengin
Another photo of Citrine with a brocken nose, happened on the world cup in a Chech Haven,on line 45 upwards a motor fly out from fuse and flew away,motor was without back support Motor is Q-80
Another photo of Citrine with a brocken nose, happened on the world cup in a Chech Haven,on line 45 upwards a motor fly out from fuse and flew away,motor was without back support Motor is Q-80
In some modeles you my need to reinforce the nose like I did in my Xigris, see post 300.
http://www.rcuniverse.com/forum/m_93...12/key_/tm.htm
Best regards,
Isaac Najary
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RE: New OXAI CITRIN by Wolfgang and Roland Matt
Yes,the best way to reinforce nose with carbon for Q-80 they have a lot power and gyroscopic efekt ,but with rear suport better.For Hacker С-50 sufficiently thickness nose.
I am looked in threemy friends, the same situation nose of airplane(other f3a models) with Q-80 brocken,after of strengthening of nose and install of back support fly until now.
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RE: New OXAI CITRIN by Wolfgang and Roland Matt
Hi guys,
I just finished my Citrin and maidened it. It is really a great flying plane, nice and relaxed flight but the aggresive side is there when you need it. The only issue I have is that it is quite a lot tail heavy, if I use batteries such as the lightest TP4400, it surely won't balance out. I'm usinh the hacker C50-13XL. Any suggestions?
Regards,
Adriel Mesias
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RE: New OXAI CITRIN by Wolfgang and Roland Matt
Hi Adriel,
That is not surprising. With a light motor, spinner and prop you will struggle to get the CG forward to the recommended spot using a light flight battery. You need to get everything as far forward as you can. That is all you can do, and if the CG is still too rearward then consider using a heavier prop.
I installed my Rx and switch as far forward as I could, and have the Rx battery right next to the motor. Even with a 1130g flight pack the end of the pack is within 3cm of the back of the motor.
Regards
Clint
That is not surprising. With a light motor, spinner and prop you will struggle to get the CG forward to the recommended spot using a light flight battery. You need to get everything as far forward as you can. That is all you can do, and if the CG is still too rearward then consider using a heavier prop.
I installed my Rx and switch as far forward as I could, and have the Rx battery right next to the motor. Even with a 1130g flight pack the end of the pack is within 3cm of the back of the motor.
Regards
Clint
#111
Mine was well supported at the rear and still blew the front off.. My feeling is that the ply ring and mounting plate which is made of ply is the problem. IMO they should be
replaced with a carbon set. I have since brought a new fuselage and fitted a pletty advance with carbon mounting. Its now done about 600 flights without any problem.
replaced with a carbon set. I have since brought a new fuselage and fitted a pletty advance with carbon mounting. Its now done about 600 flights without any problem.
#112
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This is what I did with mine:
first I took out in a piece of paper the outer geomoetry of original plate from Oxai and then threw it to the garbage.
Then I took two 1/8" midwest ply (not lite ply) and made five layer: carbon - ply - carbon - ply - carbon which ended with a little bot more than 1/4" thickness. Then passed the outer geometry, and then drew the holes of the engine directly to this plate, so no intermediate cross or any plate in between the firewall and the motor so only one piece from the fuse to the motor. the only downside of this is that it will be hard to put a new motor different than a Q80 in the future. Even using the original geometry as you can see in the picture, i had to trim it a lot.
then I glued the firewall using 30 min epoxy and very little microballoon.
then i drew the rear suport and my firend Federico drew it in autocad for me. We laser cut the support in normal 1/8" ply and had it laminated with 2 oz carbon on both sides. i used a solid carbon rod to put inside the motor and 4 mm metric screws with washer, locknut and loctite. this is not the lightest setup, but i had enough weight to spare and i am not a big fanof super light biplanes. I now have a final weight of 4920 which is fine for me. On the other hand this is the last place on a Citrin I´d play to save weight.
Here are some pics of the set up if somebody wants the cad or pdf on scale 1:1 drawing, I can share it no problem, just email me [email protected]
i have now around 150 flights with the citrin from January 20th this year with absolutely no problems.
Marcelo
first I took out in a piece of paper the outer geomoetry of original plate from Oxai and then threw it to the garbage.
Then I took two 1/8" midwest ply (not lite ply) and made five layer: carbon - ply - carbon - ply - carbon which ended with a little bot more than 1/4" thickness. Then passed the outer geometry, and then drew the holes of the engine directly to this plate, so no intermediate cross or any plate in between the firewall and the motor so only one piece from the fuse to the motor. the only downside of this is that it will be hard to put a new motor different than a Q80 in the future. Even using the original geometry as you can see in the picture, i had to trim it a lot.
then I glued the firewall using 30 min epoxy and very little microballoon.
then i drew the rear suport and my firend Federico drew it in autocad for me. We laser cut the support in normal 1/8" ply and had it laminated with 2 oz carbon on both sides. i used a solid carbon rod to put inside the motor and 4 mm metric screws with washer, locknut and loctite. this is not the lightest setup, but i had enough weight to spare and i am not a big fanof super light biplanes. I now have a final weight of 4920 which is fine for me. On the other hand this is the last place on a Citrin I´d play to save weight.
Here are some pics of the set up if somebody wants the cad or pdf on scale 1:1 drawing, I can share it no problem, just email me [email protected]
i have now around 150 flights with the citrin from January 20th this year with absolutely no problems.
Marcelo
Last edited by Mvelez; 10-01-2013 at 05:57 AM.
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Hi guys,
I have a Citrin that i bought earlier this year and due to other activities, it's not getting the attention and flight time that it deserves. I'm thinking of selling it and giving it a better home and using the money for a dire need right now. I have two flights on it and it's equipped with nothing but the best components, everything is top of the line. No scratches no nothing, everything is perfect. I still have the purchase invoice for this model, email me if you're interested and I'll inform you about the equipment on it and maybe agree on a price.
Contact me at: [email protected]
Best regards,
Adriel Mesias
I have a Citrin that i bought earlier this year and due to other activities, it's not getting the attention and flight time that it deserves. I'm thinking of selling it and giving it a better home and using the money for a dire need right now. I have two flights on it and it's equipped with nothing but the best components, everything is top of the line. No scratches no nothing, everything is perfect. I still have the purchase invoice for this model, email me if you're interested and I'll inform you about the equipment on it and maybe agree on a price.
Contact me at: [email protected]
Best regards,
Adriel Mesias
#114
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Got my Citrin finished recently. This is the first bipe I've flown and so far I'm happy. It is very different from my Spark so I'll need some time to get used to it but it flies beautifully and I really like how it feels in the air.
My equipment are:
Hacker Q80-14xs
Hacker MasterSpin 99
Mejzlik 20x13 3-blade
82mm Marquet spinner with cooling slots and marquet insert
Futaba 7008 receiver
6x Futaba BLS 173SV
1x Futaba BLS 171SV
PowerBox SmartSwitch
MK axles
MK 55mm wheel
Original Oxai links and servo tray
3mm Carbon Herex sandwich plate for battery tray
.6 mm rudder wire
800 mAh 2s lipo
10s5000 mAh main pack
Total weight with everything except the main pack is 3740g. I'm running SBUS on all the servos except for the rudder which plugged straight to the receiver channel. The power is unregulated 2s lipo.
I've flown about 6 flights on it and haven't settled on the CG yet. It pulls to the canopy on KE but there is no need for a rudder-aileron mix. I have my CG on the recommended 115mm. It seems to be a good starting point. I've tried a more forward CG but it seems to pull more to the canopy so I think I'll fly on the recommended CG a bit more. I didn't have any issues with getting enough weight on the nose. Actually the opposite. I could use a tad more weight on the tail. I will try a lighter pack.
Here are some pics during install, measurement and testing. I have changed some of the parts since these was taken so I'll post the final build pictures later.
My equipment are:
Hacker Q80-14xs
Hacker MasterSpin 99
Mejzlik 20x13 3-blade
82mm Marquet spinner with cooling slots and marquet insert
Futaba 7008 receiver
6x Futaba BLS 173SV
1x Futaba BLS 171SV
PowerBox SmartSwitch
MK axles
MK 55mm wheel
Original Oxai links and servo tray
3mm Carbon Herex sandwich plate for battery tray
.6 mm rudder wire
800 mAh 2s lipo
10s5000 mAh main pack
Total weight with everything except the main pack is 3740g. I'm running SBUS on all the servos except for the rudder which plugged straight to the receiver channel. The power is unregulated 2s lipo.
I've flown about 6 flights on it and haven't settled on the CG yet. It pulls to the canopy on KE but there is no need for a rudder-aileron mix. I have my CG on the recommended 115mm. It seems to be a good starting point. I've tried a more forward CG but it seems to pull more to the canopy so I think I'll fly on the recommended CG a bit more. I didn't have any issues with getting enough weight on the nose. Actually the opposite. I could use a tad more weight on the tail. I will try a lighter pack.
Here are some pics during install, measurement and testing. I have changed some of the parts since these was taken so I'll post the final build pictures later.
Last edited by awry; 03-10-2014 at 04:44 AM.
#115
Settings...
After many years being stored in the box, i finally managed to build my Citrin.
I looking for a good start for deflections, for normal flight, snap, spin etc
Also, what would be the best CG ? 115mm ?
Thanks in advance,
Ro
I looking for a good start for deflections, for normal flight, snap, spin etc
Also, what would be the best CG ? 115mm ?
Thanks in advance,
Ro
#116
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sorry you have had no replies .Well done on getting it built at last. Still the prettiest f3a biplane out there. I an flying with the cg a little to the rear of 115, but I would start at the recommended position. As for control throws, thats all down to personal preference so start with the standard 10 degrees or so.
enjoy flying it.
enjoy flying it.