RC4

How do you tighten/secure the prop adaptors that come with the Himax and GWS 6.6:1 gearboxes? The round spinner nut has a hole through it, what is that for? I tightened that spinner nut with a pair of needle nose pliers, and the prop (along with the entire prop adaptor) made a spectacular takeoff while the plane stayed right on the ground... Hahah, it was actually pretty funny since noone got hurt.

I'm using an APC thin electric 12x6 prop on one of the new Himax aluminum 6.6:1 gearboxes.

I hope someone can help me, cause I'd like to be back in the air tomorrow.

Do I just need to tighten the crap out of it? Is there a trick?

RCH Pilot

My Feedback: (4)

Just put a small allen wrench through that hole in the spinner nut and use it as a "handle" to tighten the nut while you hold the prop stationary. Hope this helps.

vanman

My Feedback: (2)

of course for 2 bucks you can simply replace the short shaft with a longer threaded one and be able to use the less expensive GWS props again.

Max products now has the threaded shafts for their gearboxes or you can use a standard GWS prop shaft and file off the knurls that held the plastic gear in place so the himax gear will slide over the shaft.

GWS prop shafts = $1.50ea...... MPI prop shafts = $2.00ea....both are available at his-hershobbies.com

Bill

RC4

Thanks for the tips. The allen wrench did make things tighter. I already bought the threaded shaft for GWS props, but I wanted to try out the APC prop first because it seems to be a much better design. It also seems to be better balanced. It is a little heavier, but hopefully it will produce enough extra thrust to compensate. If the prop flies off again, though, its back to GWS props.

crewchief_432

a drop of loctite on the shaft helps also

RC4

Well, after some flight testing and comparing the weight difference, I've concluded that the GWS prop is definitely the best option. The plane was very nose heavy with the APC prop, spinner nut and prop adaptor. It sounded really cool, but it flew like crap.

Anyway, I weighed the plane with the GWS prop, a threaded shaft, and no safety spinner (loctite on the retaining nut). I also weighed the plane with the APC prop along with prop adaptor assembly. The difference was more than I thought - about half an ounce. To a foamy plane, adding half an ounce to the nose makes a huge difference.

Here are the specs for anyone interested:

3dFoamy Pitts (blucor)
Carbon Fiber landing gear
Du-bro 1.5" mini lite wheels
Some extra glue, tape and graphite rods for crash repairs
Pull-Pull setup on rudder and elevator
Four Hitec HS-55 servos
Du-Bro micro aileron pusrod system
Himax aluminum 6.6:1 gearbox
Himax 2015-4100 motor
Phoenix 25 amp ESC
ETEC 3s1p 1200 mah battery
Hitec Electron 6 ch receiver

with GWS prop (no safety spinner) = 16.3 ounces

with APC prop (and prop adaptor) = 16.8 ounces

Yogi

My Feedback: (2)

There is a small shoulder that protrudes beyond the face of the drive hub which will not enter the APC bushing adapter. Take a NO 11 xacto knife and chamfer the adapter bushing in the prop so that it sits flat against the drive hub and a little extra so the collet can pull further into the drive hub a little 609 locktite on the shaft before install is also recomended but wont help if you dont cut the chamfer. Yogi

LarryC

I tool sand paper and roughfened up the gearbox shaft some before putting that adapter on and that worked wonders
the prop hasnt come of since