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Probably a dumb rookie question

Old 08-23-2014, 08:19 AM
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Default Probably a dumb rookie question

Can I cut 1" off either end of a 22" prop and re-balance, it's too much prop and I hate it. Too much load to peak RPM.
Old 08-23-2014, 10:09 AM
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It's not ideal, but I've done it.

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Old 08-23-2014, 12:12 PM
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Ok well I've just joined the ranks too, cut 3/4" straight off each tip and then shaped to somewhat rounded tips, carefully tapered the leading and trailing edge.
The engine turned 62k before and now 65k never turned any screws. i feel a little better for the engine RPM's but still hate the prop but it's all I have right now to fly with. I'll get me a Vess 22x8 one of these days for I would want to see the engine turning at least 7K.
Old 08-23-2014, 09:44 PM
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Just curious, why are you looking to run the engine at 7K?
Old 08-24-2014, 05:16 AM
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I prop the engine to achieve it's max recomended RPM 1200-7800 (3MM/TMM 53cc) I was thinking anything below 7k is lugging the engine and not getting best performance. pitch for speed or pitch for power but keep close as possible to the max RPM.is what I'm trying to achieve without having to buy another prop.
Old 08-24-2014, 06:40 AM
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Those ratings usually don't mean much. What I have found is that the peak powerband for most 50cc engines is right around 6,500. Depending on the airplane, for an aerobatic airplane a PT 23x8 or Falcon 23x9 fits the bill, for a warbird or sport model a Mejzlik 22x8 or 22x10. A gasser will not develop it's peak power until you get 25-30 runs on it. During that time you can see up to 300 rpm increase. Buying a new prop may be the only path to your goal. What brand and size are you running now?
Old 08-24-2014, 07:07 AM
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I got two props with this engine I bought, both are 22x8-14 multi pitched so now have 1 that's been hacked and one not.
My last flight went dead stick caused by a small tear in the silicone boot insulator (spark intermittent) I've repaleced the boot and all is good, been just screwing around with it at home, been windy and rainy last few days.
Oh yea the props are just run of the mill Zingers and the motor been run in the air only three times and each time is one thing or another like forgetting to remove fuel vent plug ect all operator errors, it's an 18lb weeks special bipe.
Old 08-24-2014, 05:36 PM
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Well, I can tell you that your Zingers are about the worst prop you could be using. An ideal prop for that airplane would be the Falcon 23x9. That engine with the Falcon will give you 6,200 to 6,400 and that would be right in the powerband for that engine. I had a 95" wingspan Laser with a DLE 55 and that Falcon prop and it was unlimited vertical. With your draggy bipe and 2 extra pounds you won't be unlimited but you will have good solid vertical, much better then you will with any Zinger.
Old 08-24-2014, 07:08 PM
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Zinger makes superb props and I have been using them for all my gas engines and before that on my .60 size engines with absolutely no issues. Find the right diameter and pitch for your model and there is absolutely nothing wrong with them. In fact, they are the most popular prop at the field I fly at. Dan.
Old 08-24-2014, 07:21 PM
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Dan, have you ever tried a Falcon, PT or Mejzlik prop? I only ask because in the past 30 years I can't recall seeing a single Zinger prop on an airplane where the owner was performance minded. Granted my opinion would be different if we were talking about a .25 or .40 sport airplane ( although I would still recommend APC ) however we are talking about a 50cc airplane. I would be willing to put 100.00 on the line that I know any of the props I mentioned will noticeably out perform the Zinger.
Old 08-25-2014, 02:10 AM
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Thanks guys, for now until i get some more flight time all i need is a prop that will make the plane fly, I'm not savy enough to really know the difference but I'm pretty good at tuning small engines, Prop loads and engine performance all stem from my boating days, I have experience with performance props vs run-of-the-mill in that area and it makes a HUGE difference on the seat of the pants meter. I'm sure it's the same with aircraft but i'm struggling now just getting down in one piece and will probably break a few more Zingers before I go to a perforrmancy prop.
Old 08-25-2014, 08:11 AM
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Speed, the performance I get with the Zinger props is exactly what I need for the type of flying that I do and that does not include “unlimited vertical” as the guys usually put it. Maybe the Zingers will do that if I bring a selection of props with me to try out. I will say that I can climb out with them but the planes do after a while, a long while. Dan.
Old 08-25-2014, 03:21 PM
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Dan, I have seen pictures of your beautiful scratch built airplanes. I am quite partial to your Macchi as that is the airplane I have chosen to pylon race for 5 years now. I mean absolutely no negativity by this but I do consider them " circle flyers ". The OP had asked about gaining performance via trimming a prop to gain RPM. Knowing that the airplane in question is a Weeks Special and clearly an aerobatic airplane, I suggested the appropriate makes and sizes of propellers. This does not mean that I think that Zinger props suck across the board, just that they suck for an airplane that needs good vertical performance. Granted they are less costly however what good is a 1,000.00 airplane that lacks flight performance to save 50.00? IMO that's like running no name bias ply tires on your Ferrari.
Old 08-25-2014, 03:47 PM
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Speed, thanks for the compliment. Dan.
Old 08-25-2014, 06:10 PM
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Originally Posted by speedracerntrixie
Dan, I have seen pictures of your beautiful scratch built airplanes. I am quite partial to your Macchi as that is the airplane I have chosen to pylon race for 5 years now. I mean absolutely no negativity by this but I do consider them " circle flyers ". The OP had asked about gaining performance via trimming a prop to gain RPM. Knowing that the airplane in question is a Weeks Special and clearly an aerobatic airplane, I suggested the appropriate makes and sizes of propellers. This does not mean that I think that Zinger props suck across the board, just that they suck for an airplane that needs good vertical performance. Granted they are less costly however what good is a 1,000.00 airplane that lacks flight performance to save 50.00? IMO that's like running no name bias ply tires on your Ferrari.
Now I certainly can see your point, but it's grandma driving the Ferrari and She hasn't gotten the hang of the clutch yet.
Bottom line is that I don't want to lug the engine down with too big of a prop, it's barely broken in. I went to the club tonight to give it a go but there was not a sole there, I waited an hour and gave it up, see our field has a no fly solo rule as it's right on the tail end of the full scale airport runway, try to talk my wife into spotting for me tomorrow even though She would much rather watch paint dry,
Old 08-25-2014, 07:48 PM
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Smart choice. Flying alone is just too dangerous. I have had a gasser kick back on me a time or two. Nothing serious but if it ever happens to the point of needing medical attention I don't want to be alone.

For break in the Zinger will work just fine. The biggest issue with them in the larger sizes is that the blades are thin. This allows them to flatten out some at the higher RPMs. Keep in mind though that gassers don't require much break in. I typically use the same prop I intend to use for the duraration. The only difference is that I bump up the oil an additional 10:1 for the first 5 hours of running.
Old 08-27-2014, 03:17 AM
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Flew the Weeks last night and the cut down Zinger pulled just fine for what it's worth, then on landing I touched down just 6" short of the pavement in the rough, the break away nylon bolts on the landing gear severed and the plane belly slid 50' across the pavement. The prop is history, one bottom wing belly has bad road rash along with one damaged servo and strut link connection broken off the aileron.
Old 08-27-2014, 07:26 AM
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Bummer. Hope the repair goes well.

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Old 08-27-2014, 05:41 PM
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Well I hope you don't have too much of a problem repairing the bird.

That said; Zingers are really great props for stirring paint, despite All Day Dan's assertion. That engine isn't exactly what you'd call a power house either. I know that WildHare sold some of them but I was never really around one.

For comparisons sake; my ZDZ-50NG on a Pitts type in cowl muffler or an MTD canister, will spin a Mejzlik 22x8 carbon fiber prop at 7200 RPM on the ground and a tad faster in the air. I will guarantee you that the Mej prop is a whole lot more load than a Zinger of a similar size/pitch....
Old 08-27-2014, 06:26 PM
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Agreed, one of the reasons I suggested the Falcon, it has thinner blades and will spool a bit better. My DLE 55 did really well with the 23x9. Maybe for this a 22x9 would be the way to go. They are only 66.00

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