Hey Guys;

I am putting together my first Warbird with Mechanical Retracts and using a Retract Servo, a Hanger 9 60 size Spitfire; I will be using the Hanger 9 Mechanical Retracts that came with the plane, but I have replaced the wire gear with some Robarts Robo Struts mounted on a 1 3/4" X 3/16" Wire with Robarts 3 1/4" Scale wheels; I noticed that these retracts are now a little heavier, and I have elected to use a Hitec HS-75BB Lo-Profile Retract Servo which puts out 92oz Torque at 4.8Volts; will this be enough? or should I go ahead and get the JR791 Lo-Profile Retract Servo which puts out 260oz Torque at 4.8Volts?

Thanks.

The 75bb will be plenty

Thanks for the reply; I wasn't sure, when I manual extend and retract by pulling/pushing on the retract pushrod, it seemed like a lot of weight for a servo to have to push, not sure how much ozs of force I was needing to manual move the retract; I already have the 75BB and if it doesn't do the job I can always upgrade to the JR 791 later.

Hi,
I have the same set-up on my Spit, stock retracts with Robo struts. I use the JR 791, had a 75bb and though it was just marginal. Have had over 25 flights so far, retracts work flawlessly.
Frank

Frank;

Thanks for the reply; clear something up; you said you had 25 flights on the Hitec 75bb or the JR 791? Also, are you using the heavier Robarts Scale Tires/Wheels?

Doug.

Doug,
That was 25 with the JR 791, I tried it once with the 75bb. I`m not a bib fan of the 75bb.
Frank

Or you could simply run your system at 6.0 volts instead of 4.8 and you will get a nice little boost up 113 Oz/in or thereabouts. Airplane will fly better/easier also.

John

My favorite is the JR 791 is the best in my opinion. One thing I hate is taking a perfectly good airplane apart to upgrade it later... so I put the best in first.