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View Full Version : B-29 Super Fort 1050mm (41"?) span ARF (CHEAP!)


CorsairJock
01-06-2006, 05:01 PM
Anyone who has been on eBay within the last year or so has seen these cheap 2 channel ARFs. Control is via included 2 channel transmitter: left stick turns all motors ON or OFF ( NOT proportional), right sticks gives directional control by shutting off power on on side of wing.
I flew mine one time as is. At 378 grams/ 13.35 oz, climbout was adequate, but it was banking slightly right so I tried to correct. WARNING: Do NOT hold directional control down for mor than about 1/2 second at a time, or it will quickly spiral downward in the direction toy are attempting to turn. Result: CRASH! BUT, very repaiable.

OK, so now I am finally getting around to repairs, only I have just thrown away the included Tx & Rx, as I will be installing REAL R/C equipment.

By using one of those inexpensive recievers from Hobby Lobby (5 ch, 4.5 gr. $15 w X'tal) and 2 of their Blue Arrow 4.3 gram servos (again from Hobby Lobby: about $10 each), and a 2 cell, 950 mAh LiPo battery pack, I intend to make it lighter yet very controllable. My battery is about 30 grams lighter than the included 6 cell NiMih pack, so I'm off to a good start.

I know that I won't be the 1st to attempt such a conversion, as I witnessed a Mac Hodges Wannabe along side Mac Hodges's GIANT B-29 at the Henderson, KY annual Fall Fly-In this year, and that little one even dropped a miniature X-1 like it's BIG brother (only the mini one was not rocket powered).

So, I will post updates and invite ANYONE else who has performed such a conversion, OR is thinking about it, to participate/ contribute to this thread.

CorsairJock
01-08-2006, 06:16 PM
1st update:
While trying to glue all the foam pieces back together on the fuselage, I discovered that 1 piece of the puzzle was missing. HECK With It. I've got another complete one, N.I.B. in the basement, so rather than spend precious time to repair this one, I'll get the fuselage out of the other one.
I have also decided to use rudder for directional control, rather than ailerons. There appears to be ample dihedral, and it means I will need only 2 servos instead of 3 (I would have used 2 for ailerons, + possibly some extentions).
I also purchased a Blue Arrow 15 amp, 2 cell Li-Po ready ESC at eBay for less than $15 shipped.
Thus, I anticipate total cost for this project to be less than $100. This does not include battery, which I already have and use in other aircraft as well, NOR the transmitter which I also use for other aircraft (Futaba 7CAP).

Cost breakdown:
B-29 'RTF' airplane:.......................under $40
Blue Arrow Rx w X'tal:............................ $15
Blue Arrow 4.3 gr servos (2 @ $10 ea):.... $20
Blue Arrow 15 amp ESC:......................... $15
_______________________________________
TOTAL:............................................ ....... $90

Now for additional weight & C.G. info:
My second assembly comes it at 380 grams RTF, minus decals and landing gear.
No instructions are provided for C.G., so I completely assembled and checked: it is about 2 1/2" from leading edge at root. This may sound kinda far back, considering the chord is about 5" at the root, BUT this has a tapered wing (leading edge swept back, trailing edge is straight), so I'll try it about the same place after my mods.
The Rx/ ESC which I later removed (and threw into the garbage can) weighed 14 grams. The Blue Arrow Rx & ESC combined will weigh less, probably about 12 grams.
The 3 wing hold down screws weigh about 1 gr. ea., I may replace them with something lighter.

Sky Sharkster
01-08-2006, 09:42 PM
To Corsairjock, nice going so far! I think some of these inexpensive jobs can be made to fly with modification. The sad thing is, most who buy them don't have the experience you do!
I'd be interested to hear how it works out. The weights you quoted (380gr new, 378gr mod) are so close it should have comparbale performance, but much better control.
Had a couple of questions, (that model and the "B-36" are my favorite late-1940's big warbirds) so I considered making one;
What motors does it have?
What props?
Were the origional ailerons part of the wing or partially separated ala' GWS?
Are the wings pretty strong spanwise? Need a carbon reinforcement?
How hard would it be to replace motors?
Thanks for the info so far. I'll stay tuned
Ron

CorsairJock
01-08-2006, 10:39 PM
Ron, Welcome Aboard! Good to know someone is interested in this project, hate to think I'm just wasting my time and cyberspace.

The 2 weights given are both from un-modified ones. I have 2 of them.
1st one crashed 1st time I tried to fly it with stock set-up (see ist post). All damage was confined to fuselage, so I am using fuselage from second one, and it weighs a few grams more. I expect my finished weights to be less, mainly due to using a 2 cell 950 Li-Po instead of included 6 cell 650 NiMih.

It comes with small, direct drive 'can' motors swinging 2 blade 3" props. I suppose different motors could be substituted, but it would add more work and $$ to the project. My aim is to make a small model, that will fly at a modest speeds and appear to be very high in the sky, just like the real ones.
Current draw with stock setup is about 7 amps (all 4 motors combined).

All control surfaces have molded in seperation lines, mainly for detail/ effect. I doubt the designers intended to make them movable, but they are easily seperated with a sharp X'acto knike. I am re-attaching with GWS flat plastic hinges, left over from others models. Control horns are Dubro.

Wings are pretty strong. In addition to a pretty solid/ robust plastic piece which houses motors, they (the wings) appear to have a tape applied to both sides (top and bottom), which greatly increases strength. I see no reason to add re-enforcement to wing.

The stab on the other hand, has a long slot in the middle for lining up the fin. This, and the fact that I am removing the elevators, made me decide to add a very thin (1/16" dia?)carbon fiber rod to the bottom for additional strength.

One thing this plane needs: BETTER GRAPHICS!. I tossed the included decal sheet away, will try to find some good WW II markings among my collection. I will need to pick up some 1/16" masking tape to paint a canopy/ nose section, as the included decals are are totally lacking in any form of scale accuracy.

WWI Ace
01-08-2006, 11:20 PM
Hey guys, how about a video of this thing when your done?

Sky Sharkster
01-09-2006, 12:00 AM
Hi CorsairJock, thanks for the info. I'm guessing, if those motors are like the little "Cans" on the GWS IPS motors, they're "100" size. Reason I'm wondering is there's brushless replacements (Fiego) about $ 30-35 bucks each I think. Of course ,since nobody has come up with a way (without matched motors)to run more than 1 BL motor off the same ESC, that cost gets big fast, 4 motors, 4 ESCs, maybe -$200. Oh, well, just a thought!
It's good to know the wings are strong enough, with wing-mounted motors that's always a consideration.
Well, it sounds like you've given this mod a lot of thought, I'm sure you'll get it flying! I don't know of any good graphics vendors except the regular Sig, Major Decal, etc. If there was a Guillows kit that big, I think they sell the marking separately.
Guess I'm gonna have to get onto eBay!
God Luck ,keep us posted!
Ron

CorsairJock
01-18-2006, 03:49 PM
Update:
Falling behind schedule here because of overtime at work. I do anticipate that it will be ready to fly by Sunday, Jan. 22.

The speed controller that I ordered from "markewayne (http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback&userid=markewayne&iid=6026384866&frm=284)" on ebay turned out weighing a little over 18 grams: FAR more than indicated in the description. I have therefor ordered a Great Planes ElectriFly C-12 Micro Brushed ESC w/BEC, which is advertised at 8 grams. I'll have to find another use for the Blue Arrow one. It should be here by the weekend.

Pictures below show where I cut out the fuselabe for the Li-Po battery pack that I will be using: 1st picture shows blue ink marks on area to be removed, 2nd picture shows after the removal.

As for brushless replacement motors: that would more than double the total cost of this project (maybe even triple?), no thanks. This is a stand way off model, and not worthy of such an expense IMO. If it were a Guillow model on the other hand,...........maybe.

BTW, I just ordered another B-29 thru eBay, this time for less than $26! That's right, minimum bid on some are $.99 with $24.99 shipping! At that price, I sure hope to see some more of these at this coming summer's warbird events. Imagine: a dozen or so of them flying over at the same time!

And as for a movie: I don't have the know-how on how to post, nor the time, sorry.

CorsairJock
01-22-2006, 07:55 PM
DONE!
Completed it today, and will try to fly it a little later today.

Completed, RTF weight (with battery): 367 grams/ 12.95 oz.
This is about 11 ~ 13 grams lighter than the original configuation. It also seems to have more power, apparently the 2C 950 mAH Li-Po pack has more available power than the 6C 650 mAH NiMih pack that came with the plane.

The WW II style markings are actually the original ones that have been modified: I removed the white and red bands with an X'acto knife, then applied the marking to a sheet of white stick on Coverite, then cut out the entire emblems.

The canopy was painted on by me, with the aid of 1/64" graphics tape (from local art supply store).

Sky Sharkster
01-22-2006, 11:10 PM
Hi Corsairjock, hey buddy, nice job on the build!! That cockpit detail came out good, bet it will look great in the air. Just shows what can be done with an inexpensive model if you know what you're doing!
Let us know how it flys!
Good Luck!
Ron

CorsairJock
01-23-2006, 01:44 AM
Flew it one time today (it's COOOOLD here)

Flight time according to timer on my Futaba radio (timer runs only when throttle is 1/3 or more) was just over 8 minutes. At that time, power was dropping off. Still enough to maintain altitude, but not much reserve, so I landed.
Flew pretty good, all that cheap radio gear, including that $15 Blue Arrow Rx performed flawlessly. I got it up pretty high, and at times kinda far away, and no apparent gliches.

The picture was actually must bigger, and to see the whole pic makes it seem as tho it is at a higher altitude. It has been cropped so that it will fit within the WattFlyer standards.

Hand launch went pretty well: started brisk climbout and possibly reached a scale altitude of about 12,000 ft (300 ft actual, as near as I can figure this plane is about 1/41 scale).

It was stable enough so that I was able to hold a camera with my left hand, then transfer Tx and camera so that camera was in right hand, and took this pic while holding the Tx in my left hand (not able to do anything with the Tx while I held it this way).

Not a really good pic, but the 1st time I was able to fly and take a pic of the plane I was flying while flying it. A testament to it's stability.

Sky Sharkster
01-24-2006, 01:15 AM
Congratulations, Corsairjock!! Glad to hear it all worked out. Not that I had any doubt, you understand. Say, that one-handed flying, you weren't just showing off, were you? It takes me two hands to hold a camera!
Just kidding, buddy. Good to hear it flys OK, hope to see more pics.
Ron

CorsairJock
03-12-2006, 08:36 PM
Got another flight in today, and wife took this pic.
Still hoping to see LOTS of these at this coming summers warbird events, lets' get a dozen or so of them up at once and do a formation fly-over!

nick.wright
03-22-2006, 02:13 AM
CorsairJock,

The "wanna be" is the creation of a good friend of Mac's named Chris (can't remember his last name." He and his father help Mac out at the shop for time to time. I think I saw it's maiden flight. Anyway, congrats on the mod.

vax6335
04-15-2006, 01:08 AM
That's an awesome mod, really inspires me to do my own. Wish I could afford it now, even if it is a cheap mod.

danny boy
04-24-2006, 03:41 AM
I have been debating this plane for a while now and you have convinced me I need to do one. I already have a 3ch setup so cost would be just the airframe.
Nice job, it looks really good.