kit building questions

I've taking on the task of building a topflite .60 size F4u Corsair.
I've been flying a couple of years but this is my first kit to build.
I plan on using mechanical retracts, actuating each strut with a
Hitech hs-75BB, and would like to have one strut lag behind the other
during retraction/extention. A friend advised me to solder a resistor
into one of my servo leads to slow the servo down but that seems a
little radical. Any thoughts on that? Now my next question: I will
be using 2 retract servos and 6 Futaba S3004's for the rest of the
aircraft (I'll have working flaps) and I'm not sure what size battery
to use. Should I go with 4.8v and a high mAh or try a 6.0 with a low
mAh? Any suggestions on these two subjects would be appreciated.
Gary
Reply to
ghipps
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Several suggestions. 1. I would NOT pick this kit if it were my first. 2. I'd use pneumatic retracts. Robart 615 are made for this kit. 3. The only thing a resistor (I assume in the voltage wire) would do is lower the torque. Lagging a strut is easy with pneumatics. 4. The 3004s are a little light for this plane. I'd use something like Hitec 605BB. 5. Definately use a 6v, high mah pack with a regulator. Dr.1 Driver "There's a Hun in the sun!"
Reply to
Dr1Driver
I can't give you any advice on the retracts, but if I'm not mistaken a 6 volt pack pushes out more current, which will drain it faster. If you use 6 volts, you will have to use bigger cells to have the same endurance.
Don't listen to what everybody says about not building this kit first. You could learn a lot of stuff by building a 4 star 40 first, but you don't have to. There's no reason why you can't build a Corsair properly. Just make sure to look at other airplanes built by those with more experience if you ever have a question.
Reply to
Robbie and Laura Reynolds
Get a new electrical advisor, 'cuz the one you have is a doofus.
You can indeed use electric retracts, and use a "Go-Slo" to implement staggered gear operation.
I can dig the article up, if you're interested.
Cheers, Fred McClellan the dash plumber at mindspring dot com
Reply to
Fred McClellan
"Robbie and Laura Reynolds" wrote
Not true, if using a regulator. Voltage will stay the same as a 4 cell, for a longer period of time, then it will drop like a stone. I have mine set up to read voltage of the pack, not regulated. That gives real info about the state of the pack. -- Jim in NC
Reply to
Morgans
You are mistaken. A 6 volt pack pushes more voltage, which does drain it faster. It also increases servo torque by 20%.
And that's exactly the reason he needs to start more simply.
There's no reason why you can't build a Corsair properly. Plenty of reasons. Take a look at the plans/directions.
Dr.1 Driver "There's a Hun in the sun!"
Reply to
Dr1Driver
What's gotten into you lately, DR? You have been making a lot of simple mistakes.
Ohms law dictates that if you keep the resistance the same and increase the voltage, current will also increase. E/R=I 4 volts into a 4ohm load requires 1 amp of current. 8 volts into a 4 ohm load requires a 2 amp current.
Cells in series do not increase tha Ah rating so adding another cell to the receiver pack increases the voltage without adding to the capacity of the pack.
Reply to
Paul McIntosh
Ah...I believe that's what I said when I stared that a 5 cell pack increases voltage, not current. Dr.1 Driver "There's a Hun in the sun!"
Reply to
Dr1Driver
Actually, all three of you said the same thing. :-)
-tih
Reply to
Tom Ivar Helbekkmo
No, we didn't. Adding cells in series not only raises the voltage, but also raises the current. Ohm's law is fairly unforgiving in this case.
Reply to
Paul McIntosh
You said it does NOT increase the current. That is incorrect. Current rises because voltage divided by resistance equals current.
Reply to
Paul McIntosh
Absolutely. And that's what all of you said.
Robbie started:
Dr1Driver "corrected" him:
Finally, Paul "corrected" Dr1Driver, saying:
I now challenge you to point out how those three statements are anything other than different wordings of the exact same thing. :-)
-tih
Reply to
Tom Ivar Helbekkmo
Yeah, when you increase the voltage, the current increases, thus draining the pack faster.
Reply to
Robbie and Laura Reynolds

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