Getting ready to break in my first engine, and I've a few newbie questions-
Engine is a TT-46, 10/5 MAS prop, LT-40. How tight does the shaft nut need to be? Tight as I can get it? Break in with or with out the spinner? Also, with the spinner that came with the kit, by the time I get the spinner backplate, the prop, retaining nut and bolt on the shaft, there is maybe 1/8 of an inch left on the shaft- am I not getting something here? Seems there should be more space left at the front of the shaft-
Thanks for info-
Cheers,
Brett

I use a 8" adjustable (Cresent) wrench. On the TT PRO 46, I wouldn't tighten it as tight as I could get it with that wrench. But I would give it a pretty good pull until it seemed I had all the squeeze taken out of it.

A 4 stroke is another matter. They sometimes backfire and try to kick the prop off.

With the LT40 spinner, it would be rather normal for the crank to only extend 1/8" beyond the nut.

Where did the bolt come from???

Enjoy,

Jim

bolt? duh- I was referring to the washer that goes between the prop and the nut- sorry for the wrong term- thanks
-Brett

Hi!
If you live at sea level you better use a 11x5 or a 11x6 APC prop and do not use the plastic spinner. A 10x5 prop is to small and will only make your engine rew a lot producing a lot of noice but not much trust. Never use a MA prop as those are noisy and do not produce as much trust as APC. Also remenber to balance your props (sanding on the frontside, never on the back so that you change the picth).
When it comes to plastic spinners ...you better leave it off....Better to use a aluminum spinner nut or a aluminium spinner (from Tru-Turn).
Also use 5-10% nitro in your fuel and a OS 8 or Enya 3 glowplug.

Regards!
Jan K
Sweden

Great engine and I'll have to agree on the 11-5 or 11-6 prop, but for a beginner, if your club doesn't have a strict noise rule, I would go with the Master Airscrew.

The APC props are the best and I use them on most every engine I have, but beginners tend to scuff props on the runway or break then. The MA "rubber" props will grind off on hard surface or scuff up in the grass where as the APC may break off a tip. Once you get to landing well and really want more power, go with the APC. For learning, go cheap.

For break in, don't run your engine 4-cycling rich. Give it a few, short runs just lean with cooling in between.

All good advice here. I concur with the idea of using MA propellers, I've found the APC's are going to buy new boats for hobbyshop owners....

There is another topic in play here, this is a beginner with some serious horsepower on a 'trainer'. I suggest using a 12x5 or 12x4 propeller on the engine to carve off some of that top-end velocity from the airplane, and to let the engine at idle offer a lower airspeed, so the airplane will actually come down at idle. A 6-pitch prop at idle may well be producing enough thrust to seriously flatten the approach path. Lord knows he has enough thrust available from the engine. He doesn't need an 80-mph 'trainer'. We've done just that with LT-40's and it's done good things for the trainer role. Still plenty fast, but potential to land without as much engine thrust at idle, and bags of climb performance.

I wouldn't say "serious horsepower" considering it is a TT pro on a trainer, sounds about right to me actually...

A 12 inch prop is big for the TT- just remember half throttle is a good thing!

All good advice above-

Thanks to all- much appreciated-
Cheers,
Brett

prop chart

Hey don;t fortget to tri Master Airscrew's Scimitar line of props, they give almost the same thrust as APC's while keeping the "bendable" features of the regular MA props.
For engines under .60 cu in I love these Scimitar props!!

Yes, Master Paintstick propellers are nearly indestructable, good for beginners. An 11x5 or 11x6 will give good thrust, while leaving enough ground clearance for learning to land. A 12" propeller will come too close to the ground, and will be too easy to hit in a slightly rough landing. Beginners' first landing attempts are a little more than slightly rough, if you get my drift.

As long as the nut threads completely on to the crankshaft, you have plenty of crankshaft. Don't worry about only having 1/8" of crankshaft sticking out the front. It serves no purpose once the nut is tight anyway...

You probably should break the engine in with the spinner installed, especially if you have an electric starter. The cone on the electric starter won't grip the nut properly.

Don't worry about using the plastic spinner on this engine, but when you start getting into larger engines, particularly 4-strokes, use aluminum spinners. A backfire on these larger engines will sometimes cause a plastic spinner to shatter and spread shrapnel in every direction. While probably not fatal, a piece could get in your eye and do serious damage. In any event, it's not a pleasant experience, so just don't do it, okay?

Also keep in mind that a beginner is less safety oriented than experienced pilots and those nice APC props make great meat cutters! Go ahead ask me how I know! And I had been flying for several years and to top it off, it was at a flight demonstration!

Mr. Moorman-
Thanks for info- I bought an 11-5 today.
You mention noise restrictions at the field regarding the MA prop- so I'm curious- different props, louder noise? Does it have to do with materials? Or am I completly clueless here?
Well, I am sort of clueless...
No noise restrictions at the field that I'm aware of...
Flight training starts in April...
Cheers,
Brett

The design and shape of a prop play a role in the amount of noise they make, beleive it or not, most of the noise you'll hear from your model (if you've got a muffler on it) is the prop. APC props tend to be the least noisy, and the most efficient, unfortunately more breakable than Master Airscrew. I agree that Master Airscrews are the best prop for you to learn as they'll tolerate the occasional turf slap of the beginner landing that would make throwing Knives out of an APC. Good choice on the 11x5 too.

JJ

Hi!
It's the shape of the propeller that produces noise whats is important is: airfoil shape on the blades, blade rigi.dity, tip shape, tip thickness, blade thickness blade area, blade area toward the tips..... and on and on.......
That's why most flyers choose APC (or Menz if its a wood prop)

Regards!
Jan K
Sweden

Hello, FWIW, I don't believe APC are quieter that MA, in fact, I think the oppostite.......Also, I'd "can" the plastic spinner and go to the aluminum SPINNER NUT that Dubro and others make- better looking and much less problematic.