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Find a carbon fiber tube and use it instead and glue the wings onto the fuse. It’ll be just as strong and maybe an oz or two heavier if that.
 

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Yea it’s lighter. And yes, I’d just mark where the wing butts up and cut just inside it. Slap some epoxy or gorilla glue on the roots and shove it together. Make sure to use something to hold the wings together while it dried like a couple bungee chords from tip to tip on top and bottom or maybe a ratchet strap if you’re careful, Or some good masking tape.
I did the same to my OMP slabs after their roots busted out. I never had a root rib or fuse fail even in iron man.
 

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That’s quite the weight difference! I had compared some before and I don’t think I ever saved that much. A lot of my jo40’s had thundertiger engines though so maybe they’re lighter than the old os fx’s.
goodwinds has cf tubes if I remember right.
the glue weight won’t be appreciable especially if you use gorilla glue. I’m sure it’s lighter than epoxy.
You NEED the cf tube because it’s not just about the weight but about strength. The aluminum WILL bend in a dork and you won’t be able to straiten or replace it.
that’s a fine AUW as well. It’ll fly great at 4.5-5lbs. Heck most of mine were probably 5.5lbs.
 

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I’d move the engine out as far as you need to along with the esc and lipo to get the cg before I added weight but I wouldn’t have the mount any closer to the tip of the nose than 1/2”. That’s just my personal thought. I’d rather use stand offs/spacers to get the motor pushed out a little rather than move the mount way out on the end of the nose.
But moving the motor out that far has a negative effect in that it basically adds to the nose moment (the length from center of lift to the prop). A longer nose moment will detract from pitch authority as well as rudder authority when tumbling and pinwheels and such. But so would a chunk of lead hung way out on the nose.
The good news is you shouldn’t need to move it out too far on a mojo. They CG pretty good even electric. Mine always did, anyway.
If it was built heavy in tbe tail or the servos are on the heavy side I’d say it’s worth it to move the tail servos up one bay rather than add weight or push the motor forward too far. It’s almost a requirement on a primo.

As far as lipo brands go, I’ve had the most luck and consistency over the years with the regular blue label hobbyking lipos. Recently I’ve tried some Admiral brand pack from motionrc and I’ve been impressed so far. But time will tell how they hold up.
 

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If I remember right my last Ejo40 with a G32 and 80amp esc on 4s 3300 did need an oz or two. Somehow two 3s 2200 were lighter when I tried 6s setup to get more oomph. I was never satisfied with electric.

6s

4s
 

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I like everything about nitro except buying the fuel and occasionally having a fussy or picky engine.
I hated everything about electric. I like to fly for 10min+. I hate 4min flight times. I was never satisfied with the power. With nitro you can fly WOT for 8min and the engine doesn’t give a crap. Tank after tank. Can’t do that with E.
the lack of noise, or rather a completely different noise I don’t like either. Wulfie always made fun of me for putting piped two strokes on everything I could but there’s no sound or throttle response E can compete with like a CCP.
I hate buying and keeping up with a dozen packs and yes it takes that many to give me the flight time I want per session and then I have to recharge all those and keep up with their voltage and all that. It’s not hard but it’s a pain.
some people like to say E has more power. Sure, it can on top but by my viewpoint E HAS to have more power because you can’t fly around at 3/4-full throttle. Your plane has to do most of what it does at half throttle. Sure it’s the same for nitro but when you’re really in a groove and getting nasty with it you spend a lot of time at or near WOT. E is for low and slow with the occasional ADHD twitch.

I could go on for days and reminisce about the pros of nitro vs e. I believe I have here a time or four. E works for some. It just doesn’t suit my style. Just like a fatty extra just doesn’t suit my needs and expectations. I need an edge or slick to wad up into a burr to make me giggle.
Here you go, plug. A nitro CCP beat down on the best slap ever designed. This old slab by this point had its wing ripped off twice. Once in a mid air and the next doing WOT wing tip KE touch n goes at nash. The tail was loose as a goose and so was the covering from nitro soak. It was over 5lbs at this point. The old thundertiger 46 was almost worn slick out. It wouldn’t start without a healthy prime and a starter but by hell once it did it ripped. Until it and I meet again in Valhalla 🤘🏻

Wood Fire Gas Flame Grass
 

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Gregory, that motor is out to the max imho. Pull that ESC right up behind it and put the lipo on the opposite side.
And E props are a must. I like xoar and falcon. Falcon respond better imho. I’ve become a falcon fan on gas too. Just my 2cents.
 

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I’ve always ran a degree or two of down and right thrust but a few here have made compelling arguments that none is needed on a slab at all.
 

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It sounds like you need to just go back to liquid testosterone power if you need that motor that far out and still need 8oz.

I never measured my jo40’s CG that I recall.
Do as mcddd said. Take all preconceived notions out of your head and start over with the correct setup.
Ailerons level with tube
Elevator level with h-stab
No up or down thrust in the motor (use a level for this. Set it on a table and put a level on the tube and block up the tail until it’s level. Then take the prop off and add a spinner back plate or something known to be flat up against the prop shaft and put the level against that and make sure it’s “level” (exactly perpendicular to the tube) )
Now fly it! Don’t trim it! FLY IT.
If your cg is correct you won’t need any aileron trim. If it’s off, you’ll know which way immediately. If it dives it’s nose heavy, if it climbs it’s tail heavy. Roll over and make sure.
if it keeps acting weird then you have a warp somewhere. Maybe you screwed up gluing the wings on or the tail wasn’t built square.
you can check both while you’ve got it setup and leveled.Set the level on the stab/elevator and make sure it’s level. Draw a line from the center of the wing LE to the center of the trailing edge and hold the level on that line. If it isn’t level, it’ll never and right. Check for wash in or wash out by looking down the wing from tbe tip to see if there’s any twist at all. If it has none, your wing root is off and you’re screwed.
 

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Yes move that motor back! It’ll be a different plane with the correct nose moment
 
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