I just got a new nexstar plane. I successfully flew it once so far. My Q is, Why does the nut keep comming loose on the prop when I try to start it. Every 4 spins of the darn thing!
I have it installed like this, spinner backplate(supplied with plane), prop(supplied with plane), flat washer(supplied with plane), nut (supplied with plane) and nose cone/spinner.
HELP

Just tighten the nut more or add a second lock nut.

What do you use to tighten your prop nut ? Is it tight enough ? I replace the prop washer with a Higley light lock, followed by a Dubro spinner nut for all my 2-strokers.

Lock nut huh, ok. I was wondering if it would be ok. Does anyone use the lock nuts w/ the nylon insert?
Thanks for your reply rreiss.

rajul, I use a box end wrench and crank it pretty good. What is a "HIGLEY LIGHT LOCK"? could I do a search on here for it?

You really have to put some torque on the prop nut. Most wooden props will crush a bit then swell with humidity. The black props take more tightening. A second nut will help, but I haven't used the metric aircraft nuts.

The probem with props spinnig off with a common PLASTIC spinner is... te spinner backplate is compressable.
Because the plastic compresses under pressure... you have to torque the @#%^ out of the prop nut. This crushes wood props (very unsafe Trash the prop.) making you HAVE to use a composite prop.

The plastic spinners that use a metal backplate don't have 1/3 the trouble with the starter spinning the props free... and you can safely use a wood prop. Its more expensive... but its worth it.

For the Higley light lock :

http://www2.towerhobbies.com/cgi-bin...?&I=LXL743&P=7

For the Dubro spinner nut :

http://www2.towerhobbies.com/cgi-bin...?&I=LXE158&P=7

I don't use plastic spinners anymore. The parts above are for 1/4-28 engine shaft, but you could get them for any size. Quantum Hobbies carry them too. Check it out !

thanks alot everyone.
I'm a newbie, could you tell :-)

Get a club member to help you out if you're unsure. You don't want to mess around with a spinning prop.