Twin 35mm Mig 29

[19000rpm]

I've got more use out of my little hand toss 50 & 64mm EDF's than any other aircraft this year. I can fly them almost anywhere.

So, I had to pick this one up.



Stock it is powered by 35mm EDFs, BL motors (unspecified) 2 6A ESC and 2S. It is said to fly nicely with the stock set up. But...

I plan on just ripping the ESC's out and putting in 10A's and powering it on 3S 40C.

Ray had a clone AR6300 he donated for the project. I think this is going to be fun.

[Gabe]

Xmas came early I see. Looks great 19k!

[19000rpm]

Thanks Gabe.

I'm sitting here now waiting for the UPS truck. Should be any time now. An hour and 15 minutes left in the delivery window.

It's not an official "Christmas" present so it's going to get opened ASAP.

[akent]

This should be fun!

Did you fly it stock at all?

[19000rpm]

No, I didn't fly it stock. I just got it last night. I understand they fly pretty well stock. Just not very fast.

And, I couldn't have flown it stock anyway; they mistakenly sent me a kit, which is a better deal. Now I won't have to strip out the stock components.






This thing is tiny.

[19000rpm]

I fit all of the upgrade components on the Mig 29 this AM. Battery, dual 10A ESC's, Rx and 3g servos. All is good to go. I was a little concerned that the battery wouldn't fit. Perfect. Plenty of room forward and aft to shift the battery to get the CG just right.

A bit of wiring and soldering to do to to make the twin motors and ESC's tie into the Rx. Doing this efficiently, losing as much wire as possible, and eliminating interim connectors, will save a bunch of weight, which is critical in these tiny EDF's.

I'm using a 3S 850 pack. It calls for a 2S 600 stock. Hoping the extra power will compensate for the added weight of the 850. The flight time will defintely be better.

The foam is, very slightly, warped in a few spots on the wing. Time to get out wifey's new clothes steamer! I knew that thing would come in handy for something worthwhile. ;D

[19000rpm]

I decided to use the nano connectors instead of the standard connectors and the 2.5gram servos to save weight.

I also found that the Eflite 800mAh battery is a better shape, for the compartment, and weight as opposed to the GensAce 850 .

I'm waiting on some nano extensions.

I steamed out all of the warping.

[19000rpm]

Well, as fate would have it, the nano connectors were a different type, so I opted for the nano connector that came with Rx, the clone AR6300, that converts to a standard 3 wire plug.

Since this was a kit I added 3 gram servos and twin 10 Amp Proton ESCs for 3S service.

I wired the motors and ESC's in parallel. The, "Guess which wire goes where", got me one motor wired right and the other had to be switched. Not bad.

The Clone AR6300 works. Yeeha. Bound right up. I had to remove some foam from the fuse to slide the 800mAh battery back far enough to balance.

I changed the fan blades from the stock 2S 5 blade set to the 3S 3 blade set. Ready to rock 'n roll. Got gobs of thrust.


I removed about 1" of foam to slide the battery back to get CG.


The 3 blade fan seems to be right considering weight to thrust. We'll see...


3g HK servos. Courtesy of Ray. More throw on the elevator than the ailerons. That's what they say works best on this Mig.


A nice looking plane. Ready for action. Waiting for a break in the weather...

Now they've come out with an F-86 that runs on a 30mm fan and 3S. Like, a 250mAh battery. I'm doomed.

[Gabe]

Wow - you've really taken to the ultra micro edf's - and you've modified each one! I'm a fan of the migs and I hear they fly really well! Excited awaiting the flight report.

[19000rpm]

Yep, the Mig 29-37's are great fliers. The lifting strakes on the front of the wing and the modified delta design is superb...And, awsome looking.

I may go down to a 500mAh battery for the maiden. She's awfully heavy with the 800.

[19000rpm]

Something is really wrong here. When I hand launch it, it goes about 20 ft. and goes inverted. This has happened twice.

I've double checked everything I can think of: controls, cg, wings, tails, motor installation, thrust line...I'm stumped.

[Gabe]

Really sounds like a cg issue. Hollowing out the fuse for the fan or battery at all may have made just enough difference on that small of a plane.

Very similar issues with my first Darkside Stryker (just ended in complete disaster though). It flew fine for about 20 yards and then went inverted and controlling it was out of the question.

[19000rpm]

I agree Gabe it does seem like a CG issue. Tail heavy. I've got the CG 3mm ahead of the manual's suggested CG. I guess that isn't enough.

Well, the last time it went into the snow both fans went. I'll get some new fans and move the battery forward and see if that doesn't fix the problem.

[Gabe]

Yeah, finding the cg of a plane is a nightmare. The equations are not simple by any means. When I was making that micro Stryker from scratch I had that issue and lost a few prototypes.

I'm scared to add any weight to my Darkside Stryker for this same reason. Extra carbon, fiberglass, wooden elevons, glass on the vertical stabs, plus a hollowed out battery bay. It all adds up.

Anyways - I feel your pain man.

[19000rpm]

Thanks, Gabe. Yep, it is a pain to put all the work in and have it end up a lawn dart. All part of the fun. Anyway, cosmetically, it's almost good as new.

I've found the CG charts difficult to use also. I have to admit to certain math deficiencies.

There were no fans listed on the BH website so I emailed CS and they found them. They have always been able to find parts I need that aren't listed on the website.

When I get the new fans I'm going to double check the individual fan thrust and the thrust angles. Either one, or both, of those things may be causing the problem.