RE: RedWing MX2 Build
 

yeah, actually the first 30cc sbach had it, and I think my new release is going to have a removeable stab.  The prototype currently does and I think we can get the weight where we need with it left in.  I was just curious what others thought about it. 

thanks for the feedback guys

RE: RedWing MX2 Build
 

Bolt on stab....:D

RE: RedWing MX2 Build
 

Removable Stab. Hate gluing them on.

RE: RedWing MX2 Build
 

bolt on it is! :)</p>

RE: RedWing MX2 Build
 

Whooo, Hooo

RE: RedWing MX2 Build
 

Yeah when my buddy gets them in I'll I'll post some pictures of the removeable stabs.
On the 50cc MX it looked really nice with 2 carbonfiber tubes an tabs on the underneath of the stabs.

RE: RedWing MX2 Build
 

That's a nice design; but did you noticed the price? $449 Wow!! For around $429 you can buy a 28% GP 330S that will fly as good or better with a decent 45 or 50 cc engine. Anyway I firmly believe that Redwing models outperform Aero-Works hands down.

RE: RedWing MX2 Build
 

I´m needing some help with my power setup... I cant decide what to do..

I currently own.
lots of 3c 2200mah lipos
2x http://www.hobbycity.com/hobbycity/s...dProduct=10312

1x http://www.hobbycity.com/hobbycity/s...idProduct=6233

My original thought was to use the 2 5A bec´s but i´ve just done a bench test of purely powering all the servos (uninstalled in airframe) and the thing really heats up like it is doing a lot of work so it is making me really nervous. Lets be honest, with the servos fighting against airflow over control surfaces.. the current consumed will go waaay up relative to servos sat on a desk.
The other 8A BEC arrived with an extra inline "filter" in the package added after fabrication "just incase you need to remove noise"... Ie its making me really nervous about noise...
Also that 8A BEC, has a switch built into it, which seems to only dissable the output, rather than remove the input.. Ie its inbuilt voltage display stays on when the plane is powered off!!! I´d have to dissconnect the deans from the batter between trips to the field.. but not too much hastle..

I´m using a FASST system and the servos are HD-DS090M.

I THINK my best setup would be the 8A for radio and a 5A for ignition.

Comments?
If you honestly think I should invest in something else please say so.... before the plane goes in the air i´d rather spend cash on getting it right than swearing about it after a crash!!!

RE: RedWing MX2 Build
 

What bec are you using
If the servo's are not under any load current should be fairly low.
A good switching regulator like from castle doesn't generate the heat like some regulators which waste lots of power.

RE: RedWing MX2 Build
 

Um i'm lost.. in two things..
Is the MX2 going to get a re-design to add removable elevators?
Also I though the mx2 had 2 servos in the back of the fuselage for each elevator control??

RE: RedWing MX2 Build
 

The best suggestion I can give you is to NOT use these UBECs. In my understanding UBECs are primarily designed as battery elimination systems for power application in electric powered models. In other words they are meant to be used to supply a small voltage (4.8vdc to 6.0vdc) to the receiver and a very large voltage (5.5 to 23vdc) to the motor . The UBEC is a switch-mode DC regulator separated from the ESC (ESC-Electronic Speed Controller for brushless motor), it will take high-voltage power from your battery pack and convert it to a consistent safe voltage for your receiver, gyro and servos.

If I understand correctly, in your case you are providing 11.1vDC (3S LiPo pack) to the UBEC and then only utilizing the receiver/servos output. You must keep in mind that in the case of connecting the UBEC to an ESC and then the ESC to a motor, the current through the UBEC and the ESC is much higher because of the high motor load. The fact is that when using more than 3S packs an ESC supplying a large motor, ie. >600watts (depending on prop size) will draw well over 50 amps. That means that the internal resistance of the UBEC must be very low to sustain the higher voltages and loads it needs to handle. Because you have no load on the UBEC motor output the current will be much higher through it, and it will surely overheat. Since voltage is equal to current divided by resistance; the higher the voltage and smaller the resistance the higher the current. Even with a small voltage the very small load through the UBEC motor drive circuit will produce a large current through the motor control voltage regulation transistors (MOSFET's) . This condition probably will not harm your receiver or servos, or cause any significant noise to your receiver since the current is mostly going through the motor control MOSFET's even when there is no ESC or motor present. The 8 amp UBEC that have a switch to disable the output should run very cool since it should shutdown the input to the motor control section of the UBEC.

As I understand most UBEC's are optically isolated to prevent RF generated by the motor to feed (be induced to) the receiver supply circuit. And in any case you don't have motor to produce any RF noise and in the case you are using a 2.4 system, it really doesn't matter.

General practice and experience have shown that a power supply of 6vdc through 7.4vdc is more than enough to supply a complete system as long as the batteries are of adequate capacity. A 25% model will be safe with a 6vdc system of 2400mAh or better. With two 2600mAh LiFePo4 you can supply your servos, your ignition (with a good [link=http://www.troybuiltmodels.com/items/WRCIBEFION.html]IBEF[/link]) and your total AUW will be significantly lower than with LiPOs. LiFePo4's don't have the higher Mass-energy of LiPo's, but in our application what we need is higher capacity, not higher voltage. I don't see the need of 11vdc packs in R/C planes except as primary motor power supply In the old days (about five or six years ago) most everyone was flying their planes with single single 600mAh 4.8vdc packs. We have come a long way, mostly in increasing safety and security at the expense of simplicity.

In my MX I am currently using two 1200mAh LiFePo4's packs, one switch (two will be safer, and I plan to add one in the future), one SmartFly BattShare, and one IBEF from WIKE R/C, and I am running under 10.5 lbs AUW . No regulators or any other fancy Power System required. With this setup I feel confident I can fly at least 1 to 1 1/2 hours (6 to eight 10min flights) without the need of recharging.

RE: RedWing MX2 Build
 

It looks like Tim is going to add the removable stabs on the 30cc. The servos will stay were they have always been; at the rear of the fuse.

RE: RedWing MX2 Build
 

actually it will be in my next model release that it will have removable stabs.  I have an entirely new model I will likely be releasing in the late winter.  February/March timeframe

RE: RedWing MX2 Build
 

Sounds Great

RE: RedWing MX2 Build
 

Oh okay.. I was getting confused abouth all that..
Can't wait to see what that new model is??

RE: RedWing MX2 Build
 

I'm hoping the new model is going to be a 30cc ultimate.;)

RE: RedWing MX2 Build
 

That would be interesting..
Though i would also like a 30cc Raven :D
But i think the Raven and the MX2 are 2 gorgeous planes..

Can't wait to order the MX2 to fly it here where i live :D

RE: RedWing MX2 Build
 

You Know there maybe a hint of one

RE: RedWing MX2 Build
 

No thes UBEC do not have motor outputs. they arent speed controllers.. Just lipo - 5 or 6V outputs...
So i´m confused now...
Not really understanding why these arnt suitable...

I´ve never seen a UBEC connected to a speed controller in series...... ever..

RE: RedWing MX2 Build
 

Ceecrb1 Airtech is confusing the UBECS with ESC's... Two different things... in your case the UBEC would work just fine as a regulator, But I am a true believer in redundancy so I would run two 5A ones with the diode on one of the outputs so that they can work in conjunction with each other.

RE: RedWing MX2 Build
 

That makes more sense!!

I´ll just need to find a smaller one for ignition from somewhere...

RE: RedWing MX2 Build
 

You know I have been planning a 30cc build this winter and I currently have an Aero Works 260 60-90. It is a good plane, but I am not impressed with this plane at all like some die-hard Aero Works' fans. Just putting the wings on is time consuming. Every other plane I have can be assembled at the field so much faster!

At any rate, I am seriously considering a Redwing for my 30cc build, so I am paying a lot of attention to these threads. I must admit though, Pilot really has my eye right now ;) You guys keep up the posts and I may be a Redwing flyer next spring :D

RE: RedWing MX2 Build
 

Who makes your ubec
What worries me is with your servo's not pulling much of a load your ubecs are getting warm which means it is consuming an wasting lots of power.
Have you tried a 7.2 lipo on you ubec.
If it is not a switching types an yor using 6 volts, then your ubec is haveing to disspate the other 6 volts.
If your total current draw is 1 amp then your loosing 6 watts an means your 50% efficent.
That is why a switch regulator is better becasue they are somwhere 90% efficent an run cooler.
Like I said earlier Castle makes a great switching regulator that runs cool an is very dependable which means alot when you got the kinda of money tied up in your 26% plane

RE: RedWing MX2 Build
 

T3 I may be somewhat confused since I have only seen UBECs utilized as power supply regulators when using large ESCs and very large number of battery cells on E-powered planes. Large ESCs dont have a BEC because the high current they need to handle and the additional load of a bunch of servos will overload the ESC capacity. So you need a Battery Elimination Circuit, to supply your receiver and servos. According to the product description of the hexTronic UBEC at HobbyKing they state "UBECs are used by connecting the input wires to the battery and the output to the receiver. This allows your Speed Controller to run cooler, and safer as you now have an external circuit to power your receiver. Should the Speed Controller be overloaded and fail, you still have control of your plane.

I believe I may have confused most people since the ESCs are not connected in series with the UBEC but in parallel with the battery pack.

Anyway I still don't see the need to stick two 11.1vdc LiPos packs as receiver/servo power supply. UBECs have a specific purpose, any $2 dls voltage regulator will work fine with 7.4vdc LiIon packs, A123's and they don't regulation. I don't understand why Ceerb1 wants to complicate his installation with LiPo packs when lighter LiOn's or LiFePo4's will do fine. By the way T3 waht setup are you using.

RE: RedWing MX2 Build
 

Only because if I can get the plane in the air safely and reliably, with what I already have, then there is no need to spend money on "yet more RC stuff" (to quote the wife). :D

I was thinking of running the plane off one 2200mah 3S lipo, with a Y connection, one leg to the larger UBEC for radio and a smaller 5A for ignition.