the prop i was given with this airplane has a tiny knick in it. its about a quarter inch by quarter inch are that took maybe 1 layer off the back of the prop(its still intact, just a little thin in that spot). it may not even realy be that big........

will it be ok to use it to crank my engine up with? ive broken in and tuned glow engines before, just never on a plane. i was thinking about trying to tune it and run a tank of fuel through it later this morning.

Generally the advice is to never use a nicked prop. Your nick sounds pretty small. you might want to check the balance. the nicked side may be lighter than the good side. Even up the balance by sanding some off the good side. If you do use this to run-in your engine, just make sure to never get in the path of the prop -- stay behind the arc of the prop.

ok...

were should i sand off from the other side? the tip? or in the center of the prop

ok i put it onto a rod and held the rod level. the prop does not pitch one way or the other after its brought to dead level. it also stay were i put it on the rod. im under the assumption its balanced pretty well if this is happening?

If the nick is big enough for you to question, and you can see it, then DON'T use it! It's not worth the risk. Go get another one and then break in your engine. I mean, does the thought of a few inches of plastic being impalled in you sound good? Not worth the risk--especially when breaking in the engine since you will obviously be very near the engine at all times while it is running on the ground. JMO.

wood or nylon/plastic?
I have nicked the APC type props and master air screws and kept using them. No big nicks though just small ones.

2slow hit the nail right on the head. If the prop is nicked throw it away and get another one.

why not take a picture and let us see how bad it is. i run with props that 11 x 6 that use to be 12 x 6 and it's okay. but if i chip a wooden prop, i pull it no matter what.