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skymaster337
08-27-2005, 07:49 PM
Just got a used Concept E.P. Charged the battrery, spooled it up, no lift . . .

Where do I start checking for the problem? Could it just be the battery is not putting up enough juce and I'm not getting enough rotor speed?What pitch should I have at half throttle?

Setup looks pretty stock ( brushed motor )

Any suggestions would be appreciated.


George

P.S. I'm at the hover and circuit flying with a Concept 30, so I picked up this E.P. for some indoor practice

flypaper 2
08-28-2005, 01:07 AM
George:
just got mine going after giving it a 10 yr. rest. Would run about 4 mins. and everything it had to get off the ground before the batt. gave out. About a week ago, tried a Lipo 2100 ma. batt. Lifts off at half throttle. The book says 0 degrees pitch at idle, about 8 at half throttle, 10 to 11 at full throttle. Hope this helps.

ZIGZAG
09-12-2005, 08:44 PM
Hi
I had one about 6 or 7 years ago
if i remember correctly i used a 15 turn motor and a 8 cell 1800 ma nicad pack.
8 cells 1800 was the best there was @ that time.
it would give me a good flight lasting about 6 or 7 minutes
not to bad for that time.
ZIGZAG

skymaster337
09-13-2005, 09:16 PM
Thanks Guy's . . .sure helps to hear from someone with actual time on one of these birds . . . I'v been toying with trying the new type Lipo cells but am totaly ignorant in their properties . . .Besides I don't have a charger that will handle them . . .Oh well, more learning curve . . .Thanks again,
George

skymaster337
11-15-2005, 09:40 PM
Gord,

You responded to some questions I had on the Concept E.P. Can I pick your brain on the Lipo's? How many cells?
What discharge rate works? I'd like to try getting into this (new to me )tech.What are you using for charging?What brand of cells do you recommend? How are you stopping the cells from discharging too far?What are you using for blades on yours?
Any thing you can pass on would be appreciated.

Regards, George

flypaper 2
11-15-2005, 10:19 PM
George:
Probably not much help as I'm still not satisfied with the run time. Needs a more efficient brushless I think. What I do have is, batts. 3s 1p 11.1 Volt Thunder power 2100 MA. Triton Charger.Blades are the original plastic covered foam that came with it. If I break one I'd make them from balsa with a spruce leading edge. Are your blades damaged ? As soon as the batts. lose power they can't lift off the ground long before they're depleted. Have researched a few brushless motors but havn't decided yet, more research. The Castle creations speed controllers can detect the number of cells and shuts the motor down before the voltage drops to far. I use them on some other planes. When I find a decent motor I'll post back, unless someone out there can recommend a brushless that works. Hope this helps.

DFKROFT
12-11-2005, 03:27 PM
OK, Here's one. Where does one get main blades for the "Concept E.P."?
I used to get them from Tower Hobbies. They no longer handle them.
Dave

flypaper 2
12-13-2005, 03:24 AM
Dave:
Don't know where to get new blades but wouldn't hesitate to make them. Made many for gyrocopters. Do you have the old ones for a pattern? I can tell you how to make them if you like. Had mine out today working pretty good. Bought a brushless motor for it today and I'm just installing it. Himax HC 35 10 - 1100. Let you know tomorrow whether it's any good or not. It's a shame really inasmuch as the quality is as good as or better than the ones made now. I think it was just ahead of it's time as far as motors and batts is concerned.

DFKROFT
12-14-2005, 12:10 AM
Yeah, I know what you mean. I put mine on the back burner for about 2 yrs. now. I got it back out to experiment with 'flybar-less' system. Now if the motor would stop messing up the receiver. I don't have the funds to get a 'brushless' system yet. Yeah, I know all about the caps and diode.
I guess I'll have to try a different motor. I have a few of them I can use.
Dave

flypaper 2
12-14-2005, 12:28 AM
The Himax couldn't cut it. Nothing wrong with the motor, just that RPM per volt thing. At full throttle it was turning about half what the old brush would turn. Back to the drawing board. At least it will fly on the old motor.

skymaster337
12-14-2005, 12:41 AM
You peeked my interest with the making of your own blades. Mine are the original foam ones and although they work for hovering, I'd like stronger more ridged blade for sport flying. You'd be doing me a favour with a discription of how to make a new set.

I just got a 3 cell lipo batt 4000 mah.Should be interesting to see how it performs with the rest of the set up stock.Let you know as soon as I get the Deans plugs I've ordered to hood this system up.

I've been following some of the e-helli articles being published and allthough this EP Concept is old technology by to-days standards it will be interesting to see what the modern batteries can do to the old set up.Not sure how the stock set up will handle the extra voltage from the Li poly pack but like most things in life trial and error will tell the tale.


George

DFKROFT
12-19-2005, 11:12 PM
OK, 'Flypaper2'. I'm interested in the main blade construction. Yes I have one set of the old ones. Now you got me going!
You know the original ones were foam with a wire down the leading edge.
OK, lay it on me. I have to know.
Dave

flypaper 2
12-21-2005, 02:41 AM
Guess I'd better get some blades built. Sorry about the holdup, but other obligations lately. I'll make some pics along the way.

Kepler
01-02-2006, 11:31 PM
Hi guys (first post)

I have an old EP with a Huge 500 body on it. This model is about 8 years old but I havent flown it for about 3 years. My interest in E helis has been recently re sparked with the purchase of T-Rex. Now this is a nice little model but I was quite supprized to see that the EP wasnt that far behind this latest gear.

The old EP weighed a ton with the Huges 500 body but looked great in the air. Weight was 1500 g and would fly for 4 minutes on 1700 SCRs.

I thought I would go through the exersize and find out what weight the base EP was (Minus radio gear, motor and ESC and body) I was supprized to see the weight was only 430g. Considering it is about 30% bigger the the T-Rex, I thought this was quite reasonable. So I added my old not so light JR311 micro servos (25g ea) standard reciever without case (25g) then estimated the added weight with the latest Brushless motor and lipos plus scale body. It looks like it will come out just under 1000g.

I am looking to keep this model as a sports / scale flyer so with this in mind I would appricate soe help on motor / ESC / battery combos.

I have checked the gear ratio and found it to be 16:1. I was thinking of a target head speed of 2000 rpm and was hoping for a 12 to 15 minute flight time.

So with the above in mind, I was thinking of 2500 kv motor on a 4C 2400 pack. Am I in the ball park here?

This my first venture into the world of brushless motors and LiPos so any suggestions would be greatly appriciated.

DFKROFT
01-08-2006, 12:54 AM
Flypaper 2:
Dave:
Don't know where to get new blades but wouldn't hesitate to make them. Made many for gyrocopters. Do you have the old ones for a pattern? I can tell you how to make them if you like.


OK, We, well, I'm waiting for you to show me how to build these Main blades.
Dave

mesty
09-17-2006, 09:30 PM
The Himax couldn't cut it. Nothing wrong with the motor, just that RPM per volt thing. At full throttle it was turning about half what the old brush would turn. Back to the drawing board. At least it will fly on the old motor.


I was thinking that when i readed it.
You will have to gear it up about 3 times the current pinion size !!

Take a look at the motor used on the corona, spirit or eco8. somewhere at 3000kv and 200gr must work robbe roxxy 30xx or 35xx.
and the feigao 540S and 540L.