Setup Help!! Matching Kit...

[Ultimate_Red]

How about two EDFs? Then I could go back to the smaller version and save weight....?


Here I have just fiddled around with the elevators and how the rudder would assemble.

 

[rcspaceflight]

The problem with EDF is that the plane would be even faster than with two 4x4 or 5x5 props. I don't know how small and fast you're going for. Faster isn't better because it also means that you need to keep the speed up for it to fly.

If you want it small with bigger props, couldn't you mount the motors closer to the wing tip? Instead of a slot it would be a notch.

Estimating weight and wing area will help determine where the balance of size and weight needs to be. http://www.flyrc.com/index.php/wing-load-calculator/

And a thrust calculator will tell you about how much thrust a motor and prop set up will get. Usually a 1:1 power ratio is a bit high. Depending on the plane. ... I guess the static thrust calculator I usually use isn't working. Site must be down. But you can search for one.

 

[Ultimate_Red]

Hey guys,
found this motor - http://www.hobbyking.com/hobbyking/store/__8142__Turnigy_1811_brushless_Outrunner_2900kv.html
and this prop - http://www.hobbyking.com/hobbyking/store/__22423__APC_Style_Propeller_6x4_2pc_.html
will the motor be fine with that prop? its not recommended but I cant find a 6x3 prop on HK.

Total estimated weight without a battery is ~ 104g.
tested pulling power of the motor is 165g, so battery should be about 50g or is this to little thrust? should I find a larger motor? Help!

Two of them motors should be just fine shouldn't they?

 

[Ultimate_Red]

Update:
So I've added the 6" props and the 'boxes' where the motor will be placed.


Now I'm just stuck on which battery to choose... its so overwhelming to choose a battery on HK's new system of lipo finder

now working on an EDF version.

 

[Ultimate_Red]

EDF version Complete!
View attachment 19838

Now to build the prototype airframe!

 

[rcspaceflight]

I wouldn't risk burning out the motor with the 6x4. You can always under prop an electric motor, but never over prop.

You should only need a 1:1 power ratio. So the thrust from both motors added together should equal about the weight of the entire plane. You probably want the thrust to be more than the weight of the plane, but you don't need crazy unlimited vertical on it. Unless that's what you're after.

When looking for a battery, watch out for the C rating. You have to remember that the battery is going to be supplying two motors. So if each motor takes 20 amps, then you need a battery that can supply at least 40 amps. Same with the ESC if you're only using one. But if you want differential thrust, then you want two ESCs but only use the red wire on one of them. Two red wires means they will both be powering the Rx which will be twice the power it needs and it will burn out the Rx.

 

[Ultimate_Red]

Thanks RCSF but I can't find a 6*3 on HK anywhere. can anyone help? Also thanks for the advice on the C rating and The ESCs!
Will keep you lot posted!

 

[xuzme720]

Heads Up has them but they don't ship outside the states...but at least you know the 6x3 exist.
You might try looking for EMP or GWS as those were the only 2 brands I saw with a 6x3. You could probably go to a 5x5 if you can't find a 6x3.

 

[Ultimate_Red]

Heads Up has them but they don't ship outside the states...but at least you know the 6x3 exist.
You might try looking for EMP or GWS as those were the only 2 brands I saw with a 6x3. You could probably go to a 5x5 if you can't find a 6x3.

So will this motor - http://www.hobbyking.com/hobbyking/store/__8142__Turnigy_1811_brushless_Outrunner_2900kv.html
be OK with these props - http://www.hobbyking.com/hobbyking/store/__4695__4_Blade_EP_Propeller_7x3_2_170x80mm_Pair_.html
or - http://www.hobbyking.com/hobbyking/store/__11316__6x3_Propellers_Standard_Rotating_5Pcs_Bag_.html

or how about this motor - http://www.hobbyking.com/hobbyking/store/__8493__Turnigy_1400_Brushless_Indoor_Motor_4500kv.html

tell me how you made the decision of which is best please.

 

[xuzme720]

I'd run the 2900 with the 6x3 2 blades you found. The 4 blades will smoke those motors.

 

[Ultimate_Red]

Ugh SketchUp has stopped working.. it says I have run out of my 8 hours free trial

 

[rcspaceflight]

Ugh SketchUp has stopped working.. it says I have run out of my 8 hours free trial

I ran threw my free trail and it still works. Weird.

 

[xuzme720]

I believe you can get earlier versions for free. I'm not sure, but I seem to remember reading or hearing that somewhere. Or maybe it was an Adobe CS series...

 

[rcspaceflight]

I know Sketchup recently told me that there is a new version that I could download. I first got Sketchup a few months ago.

We all know how Google never screws anything up. *rolls eyes*

 

[Ultimate_Red]

Found out that if you download he SketchUp Pro 2014 free it runs out after 8 hour and forces you to buy a licence and stops you from using it.
However, wierdly if you download SketchUp Make (same thing basically) it will say you have run out of your free 8 hour trial, but you can continue to use it as a personal education programme and not for comercial use otherwise this would be breaking the terms and conditions.... really these companies are dicks. Why can't they just make a free programme that you can use with no T&Cs? just simple and everyone can use it.

 

[rcspaceflight]

I'm glad you sorted it out. I don't remember what I downloaded, but it must have been the "Make" version. I think I just downloaded what JasonEricAnderson recommended.

Well, it is Google after all. They're just nice enough to get away with their plans for world domination without much complaining.

 

[Jaxx]

I recently found out that Google no longer owns SketchUp. It appears they sold it to Trimble Navigation.

 

[rcspaceflight]

I recently found out that Google no longer owns SketchUp. It appears they sold it to Trimble Navigation.

But we can still blame Google. For everything. lol.

 

[xuzme720]

But we can still blame Google. For everything. lol.

I know I do!

 

[Ultimate_Red]

UPDATE:
I've been gone for a little while finishing off the design and building..... this prototype!!


OK, a little naff, but you get the jist of the proportion. She flies ok-ish in the small tests I did across the kitchen (I think the tape may have affected the results a little).

Now To Order The Stuff!