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45cc Black Horse Chipmunk 85" Electric conversion


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Hi guys back from tea (theres a very British thing lol) anyway thanks for the suggestions. and yes that was how it was wired Chris. I have completely isolated the mui from the circuit now so just have a Rx pack going into the Rx and the channel 1 (JR throttle) feeding esc. The ESC is feeding the motor. It still arms and spins as you nudge the throttle up past idle........ I will try removing the red wire first just to prove it isn't that. And then I am going to pull all servo leads apart from throttle.
 
mmmmm interesting
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okay more intriguing and it is looking like Bruce might be getting the cream bun
 
It works fine with the red lead in the servo cable to the esc or without when the servo teser is used. 
 
Following Timbos suggestion  I connected a MM across the ESC batt connectors (no power cells connected) and with the red esc servo lead in place there is 9.7v present. With the red lead removed nothing. The source Rx pack is reading 6.33.
 
If I connect a power cell to the esc and measure between the red and black coming out I have 5.3v so it must contain a BEC
 
Still going to use a seperate UBEC lolol
 
Anyway lesson learned........ thanks everybody for your help
Cheers
Danny
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Hey Tom thanks  It is rather annoying I have just checked back through my purchases and found the esc and yes it is a Turnigy Plush 80A and it says all over it that it has a BEC I was being a right plonker
 
But this isn't the symptoms I would have expected for that, that's my excuse and I am sticking to it.
 
Hopefully I will be able to drag Chris along to film the event, (Friday) though our efforts in the past have usually been rather poor on the videoing fron
 
Cheers
Danny
 
 
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Hi chaps, Bruce if you can make the Greenacres leccy fun fly on July 24th and 25th next year I owe you an ice cream
 
Ross, yes I think it has been a better choice to shorten the fairing. The fairing BTW has already cracked and is only made of abs I do not see it lasting very long. A much nicer fairing could easily be made from lith plate if it comes to that.
 
Anyway the C of G has come out very close with no ballast at all. It is spot on the wing support tube. The destructions say half an inch in front of that, but when you consider the wing has a chord of 18" its not very far out at all.
 
Well I have just got to charge the packs and brace myself for the minus 1 forecast for tomorrow. Not ideal temperatures when you have a lot of fiddly rigging to do at the field
 
Hopefully my next post will have good news and a video..............
 
 
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with a BEC in the system that would explain the motor running if it was opto there should be no chance of the motor turning with just the receiver in the sytem. i missed the comment that it "drove" the motor (CHRIS i am so sorry my humblest apologies for missing a word) i thought danny had JUST said it had armed.
     with regards to the power available you cannot directly use full size - model power relation as the air molecules do not get smaller for a model  flight  i wish you luck with the maiden one thing is for sure it won't be overpowered on 2hp it will if anything be scale ish.
  as i've said i personally would have gone for  a bigger motor for sure......i would have gone down the route of powering it the same as the 45cc output would be or at least 30cc equivilant
steve
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LOL what is it with the moderators on this site, you'll do anything for sticky buns, ice cream.........
 
Hi Steve, I was using somebody's experience that has already competed with one of these Chipmunks and at national level. He uses an SC120 and not a new one either. Given that a new OS 4 stroke barely produces 2hp then Andy's is probably down on that. So I will not need much to fly the simple aeros that the Chipmunk could manage. I have a 10lb Seagull Sea Fury that most people are fitting a 4 stroke 120 in.......2hp. I am flying mine on 800 watts and it doesn't hang around, thats only 1hp. The difference between an 85% efficient powerplant and one that can barely achieve 45%
 
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Well I must first of all give a big thanks to Chris for coming out to assist me today. To say the weather was cold would be an understatement. When I left the house it was showing +1 degree and there was a good 10 -12  mph breeze. That breeze was obviously coming direct from Siberia. By the time I arrived at the flying site the temperature had dropped further and by the time you took into account the chill factor it must have been about  -273.15 degrees, absolutely all of me was frozen!!!
 
Anyway taxi trials were useless the rock hard ground was pumelling the model, so after a minute or so of trying to taxi about gave up and lined her up into wind........
 
First some pictures:




Thanks Chris for getting some great shots
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Hi Danny, I'm just beginning to thaw. It was really raw out there. I've flown off snow and been much warmer.
 
Went well though, from what I could see through a viewfinder! One day I'll see one of your maidens for real   I'm glad you cut it short anyway, fingers were starting to stick to the camera.
 
Here is the video, proves how well it went. On a warmer day when you can actually control yr thumbs it will be a real winner, with very long flight times too by the look of things. Well done.
 
 
 
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Thanks Chris, yes the flight was a bit short in this instance and also erratic, all down to me not being used to the model, it was weather cocking quite a bit more than I was expecting, more akin to a Tiger Moth or indeed your Cirrus Moth. But it felt nice despite the bitter cold. I literally could not feel the sticks under my thumbs and discretion was to land. It took off at about 3/4 throttle because i wanted to get it of f the hard ground, If memory serves, the figures showed it peaked at 60A @ 19 volts so about 1140 watts.
 
It had more than enough power for me, and that 2 minute flight used around 500mAh from a 10,000 pack so lovely long flight times with loads of touch and goes
 
I was very pleased with the landing, the ground affect kicking in just when you need it, and despite it being a peach, the farings broke loose. Probably the jarring from the icy ground.
 
The model is a bit fiddly to rig at the field but worth the hassle so that the wing is so easy to transport.
 
Anyway that just about wraps up this thread, its been fun and what a nice model. If you were to use it as a basis for a makeover it could look really nice.
 
Once again abig thank you to Chris for the video and stills.
 
Now where did I get to on the Hurricane...........
 

Danny
 
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Well done both of you...that last photo really shows the models size! I guess its pretty nigh on impossible to guage the flight due to the obvious pilot discomfort! I think I heard you mutter it may be tail heavy? It could be of course that you were simply overcontrolling her a tad...maybe lower rates or more expo might help?
As I say....very difficult to tell - you know best ...after all you were the pilot !
Good work lads, and again congrats
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Hi Timbo thanks for that, (nice Camel article, got mine yesterday) yes it was a bit erratic  honestly I do usually fly better than that.
I was frantically trying to dial in a fistfull of up elevator trim at the same time, which necesitates removing the thumb from the stick at times. The wind made it a little hard to tell on the ailerons but they seemed okay. Yes the throws need reducing, it was way to sensitive, and the 30% expo was struggling to compensate for the throws. It also seemed to pitch nose down under power, but that was very difficult to tell under the conditions. I wanted to try the flaps but was afriad I wouldn't feel my way to the sticks again, literally all feeling had gone from my finger/thumb tips.
 
Anyway thanks
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Hi
Just found this post.
Interesting to see the Black Hawk Chippie. I'm not long started on the RM 276 Chipmunk.
Test flight looked fine - nice weather for a test flight though.
Have your thumbs recovered?
I have a friend who also has the Black Hawk and is fitting the requisite petrol engine.
I'll stick to glow, perhaps a Laser 150.
Well done
Bob W
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