Help please,

I have acquired a used for i.c.  Nobler ARF and set about an electric conversion. Where did your electric version C of G end up?
All up weight is 48.5 ounces. However, it is tail heavy. Something I was not expecting as usually with electric conversions it is the other way around. I have also read that other electric conversions require tail weight. Added weight to the nose on the Great Planes cg machine and to get the manual stated  2 1/2" cg I needed to add 4.5 ounces!

4s system, 2200 lipo but I was expecting to go bigger (more weight but further back).

Thanks

Mine with a 2826 and 4s 2800 balanced at 2" behind the LE at the fuselage when I finally got the trim I wanted.  Fabulous flyer, wish I still had it.  I did rework the controls to be 3:4 instead of 1:1 which may have had some impact.  It was overpowered at 50oz with the 2826 and was to get a 2820 4s 2200 retrofit to drop the weight.

Ken

Bingo!
Found signs of weight added beneath the film, cut in, drilled and removed about 1 oz!
I then found a heavy prop nut (came off a foamie Spitfire electric model), approx 1 oz in weight. Weighed and only needed 15grams to get the balance point. total weight 48.75 ounces. Huzzah!

I am not sure about using the heavy prop nut as the motor is rear mount and I think I remember reading that there can be problems with bearings?
Anyway, if I stick to weight on the motor mount /bulkhead instead I should still bring it in at 50oz or a bit under  
 
Thanks

I have read that with i.c. power it requires weight in the tail to get good squares .....
Thanks

There are two factors IMHO that led to the Nobler ARF not doing exceptionally tight squares.  First the shape they used for the stab on the ARF.  It is flat and has a rather blunt LE.  The regular Nobler is airfoiled and has a rather sharp LE.  It produces more lift and overcomes the flaps faster.  That one you can only fix by adding a false LE - which I did since MonoKote hides your transgressions easily.  The other is that the ARF Nobler has way too much flap.  That you can fix by either changing the ratio or trimming them more like the Gieseke version.  The Gieseke flaps are at least 1/2" smaller than the stock ARF.  Some of his were even narrower, especially at the tip.  As small as 1/4".  Even with all of those changes the best corner I could get with it was measures at 12'.  A Nobler is an accident waiting to happen if flown tail heavy.  Please don't.  12' is a tight corner in today's world.  Only a handful of our top expert fliers can do a quality corner under that, and I will guarantee you it was not with a Nobler.  So, don't worry too much about the corners being tight, they can easily be flown smooth and present a high scoring maneuver.   One other thing before I get accused of Fancherizing, you have probably read about the stock controls in the ARF being "crap".  The better ones are but most are even worse.  If they haven't been replaced - beware.

Ken

There are two factors IMHO that led to the Nobler ARF not doing exceptionally tight squares.  First the shape they used for the stab on the ARF.  It is flat and has a rather blunt LE.  The regular Nobler is airfoiled and has a rather sharp LE.  It produces more lift and overcomes the flaps faster.  That one you can only fix by adding a false LE - which I did since MonoKote hides your transgressions easily.  The other is that the ARF Nobler has way too much flap.  That you can fix by either changing the ratio or trimming them more like the Gieseke version.  The Gieseke flaps are at least 1/2" smaller than the stock ARF.  Some of his were even narrower, especially at the tip.  As small as 1/4".  Even with all of those changes the best corner I could get with it was measures at 12'.  A Nobler is an accident waiting to happen if flown tail heavy.  Please don't.  12' is a tight corner in today's world.  Only a handful of our top expert fliers can do a quality corner under that, and I will guarantee you it was not with a Nobler.  So, don't worry too much about the corners being tight, they can easily be flown smooth and present a high scoring maneuver.   One other thing before I get accused of Fancherizing, you have probably read about the stock controls in the ARF being "crap".  The better ones are but most are even worse.  If they haven't been replaced - beware.

Ken

Interesting flap info, I will store that for future reference. Balance is now slight nose down on the Topflite Nobler ARF manual balance position. Should be good to go and total 49 oz.
Thanks