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Old Feb 19, 2011, 07:53 AM
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USA, KY, Lexington
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Cool thanks for the tips. Those Xoars aren't cheap though.
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Old Feb 19, 2011, 09:49 AM
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USA, KY, Lexington
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Anyone using anything but an 11x5.5 on their Rimfire 46? I tried the 11x5.5 a while ago but was thoroughly unimpressed. It seemed to make a bunch of noise but didn't actually move the plane! I was using a 12x8 and am very happy with it but I'm getting some flack in another thread stating that I'm going to kill my motor. Granted I'm drawing some really high amps (92) at a short bursts but I didn't think that would hurt the motor since it's rated for 100a bursts.

And which is more perilous for the motor amp draw or watts? I was pulling 92 amps at 1976 watts. I believe the burst watt rating is 1850.

Thoughts?
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Old Feb 19, 2011, 09:37 PM
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Canada, MB, Niverville
Joined Apr 2008
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A 12x8 is probably a bit much for this motor. They seem to like a little lower pitch and higher rpm. Just what it seems like from what i have seen with my .60. Biggest prop i use on that one is 13x6mas
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Old Feb 19, 2011, 10:42 PM
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Sammamish, WA, USA
Joined Jan 2010
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Originally Posted by emillard View Post
Cool thanks for the tips. Those Xoars aren't cheap though.
Well, if you're going to spend $80 - $90 on a motor, don't cheap out on the prop. I got mine from RCDude.com. For 12x6 or 12x8, they're $9
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Old Feb 20, 2011, 08:12 PM
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Boise, ID
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Quote:
Originally Posted by emillard View Post
And which is more perilous for the motor amp draw or watts? I was pulling 92 amps at 1976 watts. I believe the burst watt rating is 1850.

Thoughts?
Emillard, for what it's worth, here's what Hyperion states about its motors, and Amps vs Watts, and I think this means it's the amps that kill a motor:

  • Max Current (A) - These specs are for general guidance only and for <10 seconds continuous. Conditions particular to your situation - such as ambient temperature, number of cells (S) in series, airflow available to the motor, etc... - can have a profound impact on the max current you are able to safely draw from the motor. You may be able to safely exceed these specs, or not, depending on those factors. It is YOUR responsibility to check motor temperature after 10 seconds runtime and again after a short flight. If the motor feels very uncomfortable to a quick touch (or exceeds 80C measured) you should reduce propeller size or pitch. While the ZS motors can sustain higher temperatures, a properly setup model should usually obtain tremendous performance without exceeding 80C. We strongly recommend use of the Hyperion Emeter II, which measures voltage, amperage, watts, temperatures, rpm and more. This empowers you to optimize your power system performance, and insure that it will stay reliable.
  • Max Power (Watts): The same cautions as above with Max Current apply. Check temperatures to determine proper combination of battery and propeller. Note that the max watts specs are based on lipo packs which may be higher voltage than is typically used with the motor. In any case, neither max watts nor max current should be exceeded unless carefully monitored.
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Old Feb 21, 2011, 06:39 PM
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Boise, ID
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Got in some Revolver flying today, finally. Beautiful day out on the desert, light to no wind, partly sunny, and for some reason, I was the only one out there.

Found out two things:

1. Big difference between a 12x8 prop and a 13x8 prop, and a 13x10 prop. The 13x10 is what I'm sticking with. I flew 11 min and used 50% of a Hyperion 6S 5000 mAh battery. Twice. Doing touch and goes, lots of full throttle, and cruising around at about 60 - 70% throttle mostly.

2. Battery placement of an inch impacts CoG and it makes a big difference in landing this bird. Still comes in hot, but it seems to nose up slightly and settle down to almost three-point landiings, moving a little more slowly.

First pic is the battery forward, placed at the blue line on the foam. Second pic shows it pushed rearward about an inch and it performs much better, seems to be lighter, quicker, more responsive, and less up elevator.
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Old Feb 21, 2011, 10:19 PM
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Yep. I noticed that battery placement has a big affect on the CG. I have batteries all the way aft as well.

On a side note does anyone have a bouncing problem when landing the plane. My plane seems to hop severely. It doesn't seem to matter if I bring it in faster or slower the end result is the thing will not stick to the runways. Sometimes it hops up 3 or 4 feet which I don't like at all. I'm not sure what to do about this. Any ideas?
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Old Feb 21, 2011, 11:58 PM
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Boise, ID
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Yep, I bounce mine too. When I'm not breaking the LG altogether, that is.

Even on those few occasions when I seem to almost approximately grease it in, it jumps up and bounces.

Frustrating. Would sure like to get some advice about how not to do that!

My tires are the stock foamies. Maybe low-bounce Dubro tires?
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Old Feb 26, 2011, 01:01 PM
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Boise, ID
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How to land without bouncing . . .

Look what i found, over on the Parkflyers forum, on a thread about installing shocks on a Parkzone Corsair. This is by a flyer named Rick Ludtke. Only problem with this advice is that the Revolver goes by so fast, I'm not sure if I can do all this while I'm doing everything else, like trying to keep the plane going straight down the runway. I guess the solution is practice, practice, practice.



Please read Wolfgang Langewiesche's book Stick and Rudder
http://en.wikipedia.org/wiki/Stick_and_Rudder
http://www.amazon.com/Stick-Rudder-E.../dp/0070362408

In Stick and Rudder, Wolfgang explains this phenomena in detail, but I'll attempt to capture the essence of his explanation by memory:

When the tailwheel equiped airplane approaches the runway surface with too much inertia (from a rate of descent that is too great), the main wheels will touch first, allowing the tail to continue it's downward movement. The downward movement of the tail will increase the angle of attack of the wing, causing the airplane to rise back off the runway because the airplane is still traveling at flying speeds. This is problematic, because the power is either very low, or off. The resulting steep climb will cause airspeed to decay rapidly, and the airplane stalls only feet or inches above the runway, causing a hard nose-low drop back to the runway. To the unitiated, it appears as if the airplane "bounced" back in the air, when actually it flew back into the air.

The solution is a different landing technique which Stick and Rudder provides in detail.
The airplane should be held close too, but off of the runway as long as possible, so that speed and rate of descent will decay as much as possible. In doing this close to the runway (without climbing away from the runway) the airplane's angle of attack will have to constantly increase (nose pitching up) as the airplane slows down to maintain its elevation off of the runway, until the landing gear reaches the landing attitude (the angle at which the main gear and tailwheel will contact the surface at the same time).

Simply hold this 3 point attitude (by freezing the elevator input) until the airspeed decays enough to descend the airplane the final inch or so to contact the runway. Upon contacting the runway at the 3 point attitude, continue to hold the elevator fixed (as increasing the elevator could cause airplanes with landing attitude speeds faster than the stall speed to climb back off the runway) for several moments to allow the airplane to slow below it's stall speed, then apply full nose up elevator to lock the airplane onto the runway, and make the tailwheel more effective.

Reaching an exact three point attitude can be a little hard, so shoot for a slightly tail wheel low attitude at first, beause this will eliminate any threat of "bouncing" back into the air. Touching tailwheel first will allow any residual downward inertia to firmly plant the main wheels onto the runway in a manner that essentially stops the airplane from flying. If the airplanes landing attitude speed and stall speed happen to be the same (an engineering ideal), this tail wheel low technique will not work.

Give this a go (it will require practice) and let us know what you think.

Cheers,

Rick
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Old Mar 03, 2011, 06:36 PM
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Boise, ID
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Well, live and learn.

This is a really great looking plane, and I have to keep reminding myself I only bought it to learn on, so I could fly another big plane without crashing that one.

So, this weekend I learned:

1. That landing technique, above, really does work. With the battery placed an inch to the rear, the plane lands great when it comes in low, and nose slightly up, poised to achieve a three-point landing. It settles down and doesn't bounce. Right after it touches down, you can move to full up elevator, and that holds the tail wheel down.

2. The plane flies great without the canopy. (Didn't try a bunch of aerobatics, however.) When you forget to screw in the two canopy bolts, WOT will result in the canopy being blown off like somebody had hit it with a shotgun. Mine flew off, put a dent in the horizontal stabilizer, and cut itself into two pieces before fluttering to the gound out in the sagebrush.

3. Duct tape works. Put the two pieces back together. Was wobbly, but could fly around ok with it on. The other two guys in my club who saw it all suggested maybe not putting the duct tape on the fuselage, or any place I didn't want it to pull off the covering, (or near the receiver) so I kind of wrapped it around just the canopy, and didn't duct tape the canopy to the fuselage.

New canopy on order. Cost is just $10. What the heck; my canopy had a black paint smudge on the inside, so it had to be replaced anyway.
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Old Mar 03, 2011, 09:06 PM
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Well that's great to hear that you've gotten the landings down. (At least that day you did).

Funny you mention forgetting to bolt the canopy down. A few weeks ago when I landed I noticed the left wing was about 1/4" away from the fuselage. That's weird I thought. I pulled off the canopy and realized I didn't screw in the left wing. Yep I flew the plane for 7 minutes without it secured to the fuselage. Luckily the wing tube is a tight fit and there is a little bit of a bind issues where the wing attaches to the fuselage. The alignment pin and the hole in the fuselage don't mate exacty and the wing takes some effort to seat properly. Good thing too.
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Old Mar 03, 2011, 10:11 PM
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United States, KY, Henderson
Joined Feb 2006
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Quote:
Originally Posted by emillard View Post
Well that's great to hear that you've gotten the landings down. (At least that day you did).

Funny you mention forgetting to bolt the canopy down. A few weeks ago when I landed I noticed the left wing was about 1/4" away from the fuselage. That's weird I thought. I pulled off the canopy and realized I didn't screw in the left wing. Yep I flew the plane for 7 minutes without it secured to the fuselage. Luckily the wing tube is a tight fit and there is a little bit of a bind issues where the wing attaches to the fuselage. The alignment pin and the hole in the fuselage don't mate exacty and the wing takes some effort to seat properly. Good thing too.
My alignment pins the same way on one wing. For 2 years now I have been meaning to get to that, but after your comment I'll leave it!
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Old Mar 04, 2011, 11:09 AM
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Boise, ID
Joined Dec 2008
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Our planes were made on the same jigs and same run of parts, evidently. The pin on mine is off too, and the wing tube was too tight. I relieved the wing tube a bit by getting a 5/8" dowel, about a foot long, and wrapped some #220 sandpaper around it, and pushed it in and out of that hole. Took a while, but it enlarged enough to make it a bit easier to take it off.
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Old Mar 13, 2011, 02:46 PM
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United States, NJ, Roseland
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Any more flights guys?
Just finished the last bit of prep work. have the rimfire 46 on a 6s5000, spinning a xoar 12x7. 2100 watts at 90 amps WOT. Should be ok for 5-8 second bursts. Should unload a bit in the air as well. My weight is 7.76 pounds. Seems a bit on the heavy side. Battery and rx pack as far back as pos. Im balancing at 108mm. Should be ok.....At 7.76 pounds, im NOT adding tailweight! lol

I figure I'll be landing about 25 mph or so, unless you all think I should come in quicker?
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Old Mar 13, 2011, 04:45 PM
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Canada, MB, Niverville
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My plane isn't light either, not sure on what speed i land at but 25 sounds right, could probably go abit slower.
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