I HAVE SWEPT FIN FOR SUPER BANDIT COMPOSITE W/28 LBS THURST. JR SERVO CALL FOR 2721 IN BOOK 2004 BUT WILL 9411 DO FOR HIGH SPEED?

If you use the 9411, you will be giving up 34 oz. in. of torque. The 2721 will be the better choice, especially at high speed. Both are ball bearing, coreless and metal geared.
I have both types of fins for mine, (swept and standard) and have installed 8411's in them.
I was one of the two guys that had a rudder failure on a Balsa Bandit when they first came out, and am lucky to have been able to save the plane. The gear train was too weak in a smaller (easier to install servo, which is where I think you might be heading) as was the servo output arm......going with the stronger servo will be safer in my opinion....
Don't forget to install the leading edge fin bolt..............that is why I was able to save mine.....it kept the fin from departing.


Harley Condra
BVM REP
JetCat REP

Use the 8411 in the fin and forget about the issues.

Fin bolt? Did I miss that AD, Harley[8D]? Can you point me to more detail or describe what I need to do?

Thanks.

I have a 9411 servo in my Super Bandit swept fin. It has been clocked at 295mph and is rock solid. The 9411 is a digital servo so might well have more holding power than a non digital servo with more torque. It also has a less slop in the gear train than the 8411.

Re the fin bolt, if you have a Super Bandit it should show a bolt through the front of the fin that screws it to the fuse. It is not optional!

Jason

I was the other guy with the Balsa Bandit rudder issue that Harley was talking about. I have both the straight and swept fins and have 8411's in both along with the bolt on the leading edge and pull pull on the rudder. No more issues here.

DR

Hey Mike, the front of the fin originally had a carbon hatch pin installed. Remove the hatch pin and install a 4-40 bolt that goes into the rudder base with a piece of 1/4 ply under the base with a blind nut. No issue at that point. Another thing to think about is if you have one of the original carbon rods for the fin instead of the steal rod that has been in use for the last 6 years. If you plan on doing much knife edge flight, I would recommend changing the rod out.

Got it - thanks, John. That'll give me something to fiddle with for a while.