I am installing my prop again after some repairs. I fly a sig rascal40. I always had this question. Does the prop have to be touching ,leaning against the plastic stubs OR against the Stub where the nose cone screws in? My assumption is that as long as the prop is tight enough it dont matter....

Am I right ? See image. Here this is what I did, it is very tight but not resting against any of the 4 stubs...

TIA
--747

The forward edge of the propeller should be touching the small peg. This is an alignment peg in order to be able to secure the forward part of the spinner. You need to reposition the prop to the other side of the small peg in your picture, then rest the forward edge of the prop against the peg

Ken

Ken, I think it's the BACK edge of the prop that should be against the small peg. Easy way to tell though, the spinner won't go over the prop and fit together snugly if it's not lined up right.

ho2zoo - you are correct. The trailing edge of the prop should be touching the alignment peg.

yep, acourding to the picture looks like you have it correct, just make it really, really tight

Ken: No

ho2zoo: Yes

Ed: Yes

acarter: No

747 - Thake the prop off, place it so the TRAILING edge of the prop is resting against the small pins

(Ha ha, Ken got it wrong! )

If you're a beginner and have a problem with any spinner/prop alignment, sit back and think it over.

The most important consideration is that the prop not touch the holes it passes through on the spinner cone. Anything that presses against the prop blades can weaken those blades if what touches is strong or rigid. And it really doesn't matter much if the prop touches those tiny pins or not. It only really matters that the prop doesn't touch the opening in the cone. (see the 3rd picture below)

So look at how the spinner cone is aligned to the spinner backplate. And look at where the holes will line up. If we look at the spinner backplate that's in the original picture, if we place the spinner on that backplate so the screws hold the cone to the backplate, we see that the opening in the spinner lines up with the two bumps that the red arrows point to. So the prop is going to stick through a hole that lines up where those arrows point. With most props/spinners, we really need to test fit to see where the prop holes lines up with the backplate. Like in the last picture.

BTW, there are a number of different spinners available. But thinking it over works for all of them.

(BTW, the alignment posts on my spinner are NOT straight up. I used that spinner on a 4stroke and the engine did what 4strokes are good at doing, backfire. And the posts took the hit.)

Minn: Right in all cases.

Ken: I'm shocked [:@][sm=bananahead.gif] Have a hat.

Minn,
Well, I had good intentions. I was trying to say the same thing you pointed out with your pictures. Guess I just didn't do a good job of describing it huh???? Anyway, to answer the question...... What Minn said!!!!!

Ken

You now know the correct orientation of the spinner to backplate,
Now let me pass on a habit my instructor taught me.
Tighten your prop so that when you turn turn the prop counter clockwise when facing the front of your plane (same direction your starter turns it) it will hit compression with the prop horizontal to the ground.
The reason is simple enough, if/when you deadstick the prop will turn in the wind until it reaches the compression stroke of of the engine. If the prop is sitting horizontal when this happens it is less likely to strike the ground in a less than perfect landing.

747,

Throw away that plastic spinner and get an aluminum one. The plastic one will be chewed up in a week. I use aluminum on all my planes and after flying I just clean off the rubber marks from the starter and it's new again. Plus you don't have alignment pins on aluminum spinners either. I don't like anything touching the edges of my props. I've seen one come apart because it cracked under the pins pressure and stick about 3" into this guy's leg. It was a nasty site. If you can't afford the aluminum one just be ready to buy a lot of plastic ones.

Good luck,

Gibbs

NCIS,
While I too prefer aluminum spinners, there is nothing wrong with plastic ones either. I have planes that have plastic spinners on them for years with no problems at all. Spinners of any type get marred up from the starter because the starter is being improperly used. But just because a spinner is plastic is no reason to condemn it outright.

Ken

Ken,

I didn't really mean to condemn them but from my experience and you may be right about the problem being miuse of the starter but I see a lot of plastic spinners that just look awful and then they start to tear up the rubber cone in the starter. I have never used plastic because of what I've seen. I always move my prop back clockwise until it stops and not in the compression stroke and firmly place the starter cone on the spinner before I start my engines. I see many people have their props come loose because they start the engine on the compression stroke with it already right there tight on compression. Sorry if I offended you or anyone else in any way.

Gibbs

NCIS,
Oh, you didn't offend me at all. I'm sorry that I came across so harshly, I didn't mean it that way. I was just trying to point out that plastic is just fine. Yes, you are absolutely correct that a lot of planes out there look like crap because the spinners are all torn up. Too many people just don't know how to use an electric starter properly. I don't worry too much because I hand start most of my planes anyway!!!!

Ken

Now I want to know what people are doing wrong or the "proper" way of using an electric starter.

Sorry to sidetrack this thread

Thanks

Jon

The "wrong" way is pretty much what NCIS said. Most people will put the starter on the spinner with the prop directly against the compression stroke of the engine. When the hit the starter there is too much resistance from the engine to turn over and the starter just spins on the spinner. On a plastic spinner this will just eat it alive, and on an aluminum spinner it will just make it ugly. The proper way of doing it is to turn the prop clockwise until it hits the compression of the engine, apply the starter to the spinner with a firm push, and then hit the starter. This will let the starter start turning over the engine and get up a little speed before it hits the compression stroke. If it's done this way it will rarely slip.


(p.s. Minnflyer, no comments from you. I was having a bad day out of my element!!!! )

Ken

All,

Sidetrack? Me? No !!! Any related good rc info is welcome...Discuss-away you experts!

Do some of you like RCKEN hand start? I always electric -start!!!

747,
I almost NEVER electric start. The only time that I will ever really use my electric starter is when I am trying to start an engine that is way out of tune, such as a new engine or one that has been disassembled and put back together. IMHO, if you learn to hand start your engines you will have a better understanding of how they are running. I know this may sound a bit corny, but it's almost a Zen type of thing. When you learn to properly hand start your engines you can usually "feel" that something isn't right in them.

Just me 2¢ worth!!

Ken

I always use an electric starter and to be totally honest couldn't give a d^$m if it leaves a mark on the spinner or not. Whine-whine-whine, it's a toy - get over it. I might need to replace one every season or so. Whoopee. I don't worry about special adapters, bent cones, aluminum polish or any of that crap. I just fuel up and fly.

Thanks Ken, I am doing it "right", I noticed that sometimes when I hand start my engine it runs backwards, what am I doing wrong, or does it jsut do that?

Thanks

P.S. usually when I hand start it after is it warm, it starts on the first flip.

Jon

Minnreefer,
If the engine runs backwards when you start it it's because it was flooded. You need to decrease the amount of prime you are giving it.

Ken

Usually a sign of being a bit too rich(flooded). Let it run for a few seconds in reverse to warm up and burn off excess fuel. Then stop engine and restart. Should be fine. Often just moving the throttle a little will cause it to correct the rotation.

I'm not going to say a word

Thanks!!!!!

Ken

Thanks