Official RocHobby 1100mm NXT Nemesis High Speed Thread

[kenelder]

And now we've tried the 11x12 on 4s. Showed 71 amps peak, 105 mph on the GPS. I think next up I'll try 10x12 and maybe a larger battery- I think 105 on a 2200 is pretty good, but maybe more is there on a 3000. We will see......

[Westsider]

Stock ESC is 70 amp, as a reminder. Love the speed. Be careful envelope pusher :cool:

[Grossman56]

Might be best to push that up to a 100 amp ESC if you want to play around, give yourself a safety margin. If you're going from a 2200 4s to a 3000 4s, that's not going to increase your speed, it's like putting in a bigger gas tank.

Grossman56

[kenelder]

You guys are correct! Today I tested several 4s batteries from 2500 to 3300, no real difference is speed. It was a few miles per hour slower today as I cut the 11" dia prop to 10" to unload it a little. Didn't think that would slow it measurably but it did. Of course I was well under the 70 amp rating too, so down in power.

Then I unleashed it with 6s and the 9x9. This time I flew long straight lines so the GPS could attempt to be a little more accurate. Definitely much faster visibly and the GPS agreed: 118 knots. That works out to be 136 mph (which I'm not really believing), but it is very much faster than with 4s. Not to mention the howling sound of high rpms.

Since I like the flight regime with 6s, I'm going to put in a 100 amp esc just to keep from killing this factory esc. So far it hasn't missed a beat, but I like the plane too much to risk it further.

[kenelder]

Forgot to mention- Nemesis does aerobatics pretty well too. Rolling circles, loops, etc. I didn't find it hard to keep in knife edge although I have read others say it wouldn't hold the nose up. And finally- it does upright flat spins really great! You do have to work to get it in, but enough opposite aileron does the trick and then it goes pretty flat. Recovers fine after about 2 extra turns once you release the controls. It was so wrapped up in the spins that I was ready with opposite controls to stop the spin if it didn't recover, but didn't need to, recovered just fine. I forgot to try inverted spins so that's maybe next weekend.

[kenelder]

Today 134 mph on the radar gun, so I guess it really is moving that fast. Swapped in an 85 amp esc, physically smaller but came down cooler. Whatever speed it has, sure is stable and smooth. This is absolutely the easiest to fly scale plane I have. Cruises around just fine at less than half throttle, everything including aerobatics is very smooth. When it comes landing time, it is hard to believe how slow and stable it approaches the runway. I'm really pleased.

[Nickelup]

Hi kneeler are you using the stock motor with the 6 cell setup? Is the motor holding up ok? Do you just go full throttle for a short burst? Thank you

[kenelder]

Yes I'm using the stock motor. Just installed a ZTW 90 amp esc from Motion, it is the one recommended in the "upgrades" section for the NXT. I'm at full throttle for a lot of the flight, if the motor is going to cook, then I want that to happen and get it over with. But when I land the motor seems to be within normal temp limits so it may last just fine. It is still showing the same speed on the GPS so the magnets haven't cooked yet, plus the battery is around storage voltage when I land, so it is not using extra current yet. When the magnets get cooked, they lose their strength and then the kV goes up which makes the motor even hotter. It's a vicious cycle and eventually you will notice the lower flight times and speeds. But like i said, so far I've not seen anything to indicate the motor is unable to handle the power.

Keep in mind I'm using a 9x9 prop......pretty sure the standard 10x10 prop would cook the motor really quick.

Today I blew off one of my gear doors, fortunately over the runway. The wire that closes the door broke. I'm going to guess that the speed was pulling hard on the wire and maybe it strain hardened and finally broke. Fortunately the gear door fell onto the runway so it was easy to find. Bent up a new wire this evening so I'm ready to go again tomorrow. I also adjusted both doors so that they close really tight, didn't do that before and it sounded like something was flapping- it was the gear door- when it blew off the flapping noise stopped.

I may buy a backup kit just to have around. Very seldom do I ever like a plane enough to keep a spare kit, but this one deserves it.

[kenelder]

And today blew off the other gear door. The spring wires that retract the door are breaking at the sharp bend, I think that wire is too brittle. The one I made from music wire yesterday worked fine, I should have replaced them both. Still showing a little over 130 mph and nothing has broken yet.....

[Westsider]

Besides a couple of spinners and props, none of which have failed, that's the only other spare part for this plane I have had to pick up. Got a picture of your reenforcement/replacement with wire? Always looking to pilfer good ideas from this bunch

[kenelder]

Made the wire exactly like the factory wires, just used music wire I had. In fact, I traced the wire that was remaining. Doesn't matter, blew off the gear door today that I had made the wire for, looks like I'm flying without doors for a while since they are out of stock. Something else happened today but I have not discovered the reason- on the last flight of the day it suddenly needed a bunch of down trim. I landed and looked for issues with the elevator or maybe the battery slid back, but couldn't find anything. Now it's going to get a thorough inspection before it goes up again, I really don't like sudden changes in trim in really fast airplanes. Only happens at high speed, so I'm guessing maybe the motor mount is lose although I didn't see any lose screws. Something is different, I just have to find it.........

[Nickelup]

Thank you Kenelder for getting back. What brand and size 6cell battery are you using, or what size fits?

[wvrailfan]

One of the older flyers in my club, usually prefers built up wood planes, was introduced to a couple of RocHobby foamies this year, including the Nemesis. This is what he wrote for our Facebook page.

http://www.facebook.com/permalink.php?story_fbid=586920901502353&id=246849362176177

[Alpha]

That's a great writeup, thanks for posting it, wvrailfan! I enjoy both of these aircraft immensely. The Nemesis looks like a guppy from the top and a shark from the side, and it me that underscores its personality in the air. Quick and agile when you want it to be, but an absolute *****cat in the landing pattern.

[xviper]

All things remaining stock, I wonder if this would survive 5s.

[T-CAT]

The Nemesis is an amazing flying plane for the price, and hard to beat the performance.

[Aros]

Still love my Nemesis for all the reasons mentioned. AND she's still bone stock!

[kenelder]

I'm using a Roaring Top 2700 mah 6 cell pack 45C because I had it laying around. Had to remove the battery tray plate so the battery could sit a little lower- it just clears the hatch. Any larger battery and you'd need to remove some of the hatch material to get it to close. I place my pack with the leads on the bottom side- otherwise the leads hit the hatch. Based on my current measurements a 5s won't work with the factory prop, you'll likely cook the esc. If you go to a smaller diameter prop, you might as well go 6s.

I am now exploring the aerobatic range of the Nemesis. So far it is very agile and will do flat spins, but I've yet to get it into a spin reliably- more experimentation needed. When it does spin, it is great- will have you wondering if it will come out. It does a great knife edge pass with no coupling. I'm now experimenting with slower stuff trying to see how it handles aerobatics at slow speed.

[xviper]

Based on my current measurements a 5s won't work with the factory prop, you'll likely cook the esc. If you go to a smaller diameter prop, you might as well go 6s.

Do you recall by how much more than 70A was the highest draw?

[JamesonC]

Hey everyone, I'm new here but see that this page has a better following of the Nemesis than RCGroups. I just recently got one and used a radar gun to check speed and had 87mph on the all stock setup and swapped to a 11x10 and got 92mph. I used to have a Strega and ran consistently 109mph with the 11x12 prop and I was expecting at least 100mph out of this one. I have been hesitant to run a 11x12 on this plane with the higher kv motor. I'm really surprised to hear some of the speed readings I've seen in this thread. Maybe I'll give the 11x12 a shot. Right now, I think I'm more impressed with the Strega for speed!