HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Oct 12, 2009, 06:03 AM
Registered User
in eygpt
Joined Sep 2009
74 Posts
Heeeeee guys where are are you?
slloom is offline Find More Posts by slloom
Reply With Quote
Sign up now
to remove ads between posts
Old Oct 12, 2009, 09:32 AM
Real name's Teja :)
teha99's Avatar
USA, NJ, East Brunswick
Joined May 2008
1,388 Posts
most of them are folowing the little boeing 737 thread. lol
teha99 is offline Find More Posts by teha99
Reply With Quote
Old Nov 07, 2009, 04:12 PM
Real name's Teja :)
teha99's Avatar
USA, NJ, East Brunswick
Joined May 2008
1,388 Posts
Hey guys, look at this!

http://www.rcgroups.com/forums/showt...1#post13499371
teha99 is offline Find More Posts by teha99
Reply With Quote
Old Nov 19, 2009, 03:35 AM
Globemaster Maiden Time
KoziFlyer's Avatar
Melbourne
Joined Jun 2007
1,046 Posts
Been busy with work. Anybody flown their 747 yet?
KoziFlyer is offline Find More Posts by KoziFlyer
Reply With Quote
Old Dec 24, 2009, 05:19 AM
Registered User
Joined Dec 2009
53 Posts
Hello everybody - I am new here and this is my 1st post !

I have been following previous threads and I am now more than ever convinced to build the Boeing 747.

The job you have done so far is superb and definitly a great basis for me.

I have many questions, but key ones are the following :

1 - Where is the center of gravity of the plane on the plans ? How to know how to balance weight load ?

2 - Vertical tail (on the back) + the 2 tails on the main wings :
- Do we need to make the wing tails active and connect it to servos ? or no need to cut this part and better to keep it static (not dynamic, not connected to servos) ?
- If we decide to make this part active, do we need to keep 1 servo for the tail wings + vertical tail ? or 2 separate servos ? I would imagine they are all connected. Correct ?
- Is it necessary to activate the wind tails ? or just back vertical tail is enough ?

3 - Horizontal tails : as per your experiences it appears that more surface is needed. Are the plans updated ?

4 - Engines :
I would like to install 4 engines but what should be the model that needs to be installed ?
What power ? what size ?

5 - Depron :
I did not understand how you have twisted the depron over the wood structure. Did you cut the depron in order to have a circle (round) shape ? Or did you twist it ?
Whattype of depron to buy ? DO I need cutting tools ?

6 - What batteries knowing that we have 4 engines ?

7 - Size. What should be total height of the plane ?

I am now in the process of assembling the parts and working on writting a part list -- do we have a shopping list ready made ?

Thanks for your support guys !!
vicking is offline Find More Posts by vicking
Last edited by vicking; Dec 25, 2009 at 03:42 AM.
Reply With Quote
Old Jan 01, 2010, 04:06 PM
Registered User
Joined Dec 2009
53 Posts
Ok I am a bit lost in chosing the engines.

The weight of my plane would be around 1.8KG. Many recommended the 55mm ducted fan motor.. but I am not convinced by the "thurst" and it might be too limited for my plane.

Consequently I am thinking installing 4x 64mm ducted fans (http://www.hobbyking.com/hobbycity/s...idProduct=6632)

Would it be too powerful for my plane ? How many 4S or 3S batteries should be installed ? 1 or 2 ?

Thanks!
vicking is offline Find More Posts by vicking
Reply With Quote
Old Jan 13, 2010, 02:18 PM
Registered User
Joined Dec 2009
53 Posts
Quote:
Originally Posted by KoziFlyer View Post
Been busy with work. Anybody flown their 747 yet?
The major issue I amhaving is to decide whether I need 2 or 4 64mm engines.

On youtube, I noticed that you installed only 2 engines and 1 4000 Mah battery.

Am I right or should I installed 4 engines ?

What is the total weight of your plane ?

Thanks
vicking is offline Find More Posts by vicking
Reply With Quote
Old Jan 14, 2010, 01:25 AM
Globemaster Maiden Time
KoziFlyer's Avatar
Melbourne
Joined Jun 2007
1,046 Posts
Quote:
Originally Posted by vicking View Post
Hello everybody - I am new here and this is my 1st post !

I have been following previous threads and I am now more than ever convinced to build the Boeing 747.

The job you have done so far is superb and definitly a great basis for me.

I have many questions, but key ones are the following :

1 - Where is the center of gravity of the plane on the plans ? How to know how to balance weight load ? Have a look at Page 9 of this forum.

2 - Vertical tail (on the back) + the 2 tails on the main wings :
- Do we need to make the wing tails active and connect it to servos ? or no need to cut this part and better to keep it static (not dynamic, not connected to servos) ? No need
- If we decide to make this part active, do we need to keep 1 servo for the tail wings + vertical tail ? or 2 separate servos ? I would imagine they are all connected. Correct ? 2 separate servos for elevator and 1 for the rudder
- Is it necessary to activate the wind tails ? or just back vertical tail is enough ? Vertical tail (rudder is enough) what is a wing tail?

3 - Horizontal tails : as per your experiences it appears that more surface is needed. Are the plans updated ? Plans not updated as i am not the original author but there is a pic from me on one of the pages somewhere

4 - Engines :
I would like to install 4 engines but what should be the model that needs to be installed ?
What power ? what size ? Depends on the weight of your model. Let me know the weight of your model first then I'll advise power package.

5 - Depron :
I did not understand how you have twisted the depron over the wood structure. Did you cut the depron in order to have a circle (round) shape ? Or did you twist it ?
Whattype of depron to buy ? DO I need cutting tools ? White depron, you make the rib structure first with 6mm Depron, then you sheet it between adjacent ribs with 3mm Depron, top half first then bottom half, not all the way around (too hard). Cutting tools, sharp razorblade

6 - What batteries knowing that we have 4 engines ? Tell me weight of your plane first. I use one 4s 4000 with 2 motors

7 - Size. What should be total height of the plane ? Height doesn't matter, whatever the plan shows

I am now in the process of assembling the parts and working on writting a part list -- do we have a shopping list ready made ? No, each design and country supply is different, which country are you from?

Thanks for your support guys !!
Please have a look throughout this whole forum for all the advise. Most of your questions are answered throughout this forum already.
KoziFlyer is offline Find More Posts by KoziFlyer
Reply With Quote
Old Jan 14, 2010, 01:27 AM
Globemaster Maiden Time
KoziFlyer's Avatar
Melbourne
Joined Jun 2007
1,046 Posts
Quote:
Originally Posted by vicking View Post
The major issue I amhaving is to decide whether I need 2 or 4 64mm engines.

On youtube, I noticed that you installed only 2 engines and 1 4000 Mah battery.

Am I right or should I installed 4 engines ? 2 engines, 4 if you have lots of money

What is the total weight of your plane ? 2.8kg

Thanks
see above in blue
KoziFlyer is offline Find More Posts by KoziFlyer
Reply With Quote
Old Jan 14, 2010, 04:31 PM
Registered User
Joined Dec 2009
53 Posts
Quote:
Originally Posted by KoziFlyer View Post
see above in blue
Thanks Koziflyer for your answers !!

I am based in France, Paris - however everything is soo expensive here that I'll order almost everything on Hobbyking.

I am impressed by your configuration. 2 engines (total thrust of +/- 1kg) can lift the plane (2.8 KG !!)

The ducted fan is 20 USD/unit, I would like to keep as much as possible original shape.. I'll go for a 2 engines plane, but I think the plane would have some 3.5 KG for 4 engines-- or 2.7 Kg with 2 engines.

I was not expecting the plane to fly with 2 engines but it seems it flies well - I will start with thatand upgrade it to 4 engines later.

If no difference, I'll go for the 2 engines.

>> For 2 engines, I think I will follow your path and install 1 x Lipo - 4S 4000ma. What is the discharge rate of your battery ?


Regarding the "ruder wing" - sorry my English is bad, I don't know the specific word.
In order to turn, the plane can use 2 surfaces :
1/ The back vertical ruder = you have this surface active and dynamic on your plane

2/ The horizontal ruder on the wings (sorry but dont have the word). When you go left, the left ruder would go down and right ruder would go up - and vice versa :

>> Should I let these wind ruder surface active and interconnected to the back vertical ruder ? or is it possible to turn the plane right/left with only the back vertical ruder ?

So Far, this is what I am sure about :

1x 4000ma Lipo - 4S
2x EDF64 with ADH300 Motor Assembled 252W(4300kv)
1x ESC (50 ma).
4X Mini servos
1x Hobbyking Remote control (37 USD) with receiver included
vicking is offline Find More Posts by vicking
Last edited by vicking; Jan 14, 2010 at 04:37 PM.
Reply With Quote
Old Jan 15, 2010, 01:30 AM
Globemaster Maiden Time
KoziFlyer's Avatar
Melbourne
Joined Jun 2007
1,046 Posts
Quote:
Originally Posted by vicking View Post
Thanks Koziflyer for your answers !!

I am based in France, Paris - however everything is soo expensive here that I'll order almost everything on Hobbyking.

I am impressed by your configuration. 2 engines (total thrust of +/- 1kg) can lift the plane (2.8 KG !!)

The ducted fan is 20 USD/unit, I would like to keep as much as possible original shape.. I'll go for a 2 engines plane, but I think the plane would have some 3.5 KG for 4 engines-- or 2.7 Kg with 2 engines.

I was not expecting the plane to fly with 2 engines but it seems it flies well - I will start with thatand upgrade it to 4 engines later.

If no difference, I'll go for the 2 engines.

>> For 2 engines, I think I will follow your path and install 1 x Lipo - 4S 4000ma. What is the discharge rate of your battery ?


Regarding the "ruder wing" - sorry my English is bad, I don't know the specific word.
In order to turn, the plane can use 2 surfaces :
1/ The back vertical ruder = you have this surface active and dynamic on your plane (active- needed for takeoff)

2/ The horizontal ruder on the wings (sorry but dont have the word). When you go left, the left ruder would go down and right ruder would go up - and vice versa : Ahh, this is called the Aileron

>> Should I let these wind ruder surface active and interconnected to the back vertical ruder ? or is it possible to turn the plane right/left with only the back vertical ruder ? You have to have Aileron installed, very important, rudder only will not turn the aeroplane

So Far, this is what I am sure about :

1x 4000ma Lipo - 4S (25C is ok) flight time on 4000 pack is 3.5 to 4 minutes
2x EDF64 with ADH300 Motor Assembled 252W(4300kv)
1x ESC (50 ma). (u need 2 ESC's if u use Brushless motor, 1 ESC for Brushed) I recommend u use Brushless motors not Brushed!!)
4X Mini servos (HXT900) you will need at least 6
1x Hobbyking Remote control (37 USD) with receiver included

My total thrust on the 2 motors is 2.8kg (1.4kg thrust each). So power to weight ratio is 1:1.I used 2xEDF64 with SAPAC 4000kV outrunner brushless motors and 2x 80 amp ESC's. The electronics alone cost me $350 AUD.

Try to find a motor with more thrust then what you have chosen. I recommend this one maybe from Hobbycity - 2x EDF68 with 2836kv Motor&Heat-sink Assembled 1100 grams and 2x80A Plush ESC's. Love Hobbycity its cheap. I paid much more, but i got my fans professionally balanced thats y it sounds so good.

Important before u buy. Add all your weights together and see if you will have enough power to fly your plane. 1:1 is good. 2:1 (power:weight) and you should still be able to fly a jumbo, just.
KoziFlyer is offline Find More Posts by KoziFlyer
Last edited by KoziFlyer; Jan 15, 2010 at 01:42 AM.
Reply With Quote
Old Jan 15, 2010, 06:32 AM
Registered User
Joined Dec 2009
53 Posts
Quote:
Originally Posted by KoziFlyer View Post
My total thrust on the 2 motors is 2.8kg (1.4kg thrust each). So power to weight ratio is 1:1.I used 2xEDF64 with SAPAC 4000kV outrunner brushless motors and 2x 80 amp ESC's. The electronics alone cost me $350 AUD.

Try to find a motor with more thrust then what you have chosen. I recommend this one maybe from Hobbycity - 2x EDF68 with 2836kv Motor&Heat-sink Assembled 1100 grams and 2x80A Plush ESC's. Love Hobbycity its cheap. I paid much more, but i got my fans professionally balanced thats y it sounds so good.

Important before u buy. Add all your weights together and see if you will have enough power to fly your plane. 1:1 is good. 2:1 (power:weight) and you should still be able to fly a jumbo, just.
Good advices.
1/ Engines. I have several options then :

- 2x EDF68 with 2836kv - or
- 2x EDF64mm Sapac Ducted Fan Unit w/4800kv Outrunner 3s 4s - Thust 950gr each = 1.9KG. This 2nd option would be my preference because at least blades are well balanced, do you think it's too small ?

(http://cgi.ebay.com/ws/eBayISAPI.dll...ht_1567wt_1165)

ESC :
If possible, I would prefer 1 ESC for both engines. The good thing with your ESC is that it is BEC which means no need to buy another battery

Battery : 4 min fly is too low, I would prefer at least 8min fly time. Should I take 8000 Ma then ?? It is huge

Servos : why 6 servos ?

1 x for the vertical ruder
1 x for the back horizontal aileron (altitude)
2 x for both horizontal ailerons on the wing (right / left)

= 4 servos

Should I install retracting wheels ?
vicking is offline Find More Posts by vicking
Reply With Quote
Old Jan 15, 2010, 12:05 PM
Registered User
Joined Dec 2009
53 Posts
So far this is the approximative configuration/weight I have :

- 2 x EDF64mm Sapac Ducted Fan Unit w/4800kv Outrunner 3s 4s (2kg thrust) = 1100 Gr
- 2 x Plush ESC = 240 Gr
>>> Why should I take 2 x 80 Amp ESC ? 2 x 40 Amp is not enough ?
- 1 x Receiver = 150 Gr
- 5 x wheels = 150 Gr
- 6 x servos (still don't understand why not 4) = 130 Gr
- Wires/connectors = +/- 200 Gr
- Overall Depron structure as per the plan ?????

Without the depron structure, the current weight is : 1970 Gr.

Clearly, the plane would weight +/- the same than yours, so let's say 2.8 Kg.

With the same engines than yours.. currently this is the ration I have 2 : 2,8

Should I add 2 other smaller engines ? such as EDF 55 ? or can it keep it 2 engines ?

Cheers
vicking is offline Find More Posts by vicking
Last edited by vicking; Jan 15, 2010 at 12:15 PM.
Reply With Quote
Old Jan 15, 2010, 10:38 PM
Globemaster Maiden Time
KoziFlyer's Avatar
Melbourne
Joined Jun 2007
1,046 Posts
Quote:
Originally Posted by vicking View Post
So far this is the approximative configuration/weight I have :

- 2 x EDF64mm Sapac Ducted Fan Unit w/4800kv Outrunner 3s 4s (2kg thrust) = 1100 Gr
- 2 x Plush ESC = 240 Gr
>>> Why should I take 2 x 80 Amp ESC ? 2 x 40 Amp is not enough ?
- 1 x Receiver = 150 Gr
- 5 x wheels = 150 Gr
- 6 x servos (still don't understand why not 4) = 130 Gr
- Wires/connectors = +/- 200 Gr
- Overall Depron structure as per the plan ?????

Without the depron structure, the current weight is : 1970 Gr.

Clearly, the plane would weight +/- the same than yours, so let's say 2.8 Kg.

With the same engines than yours.. currently this is the ration I have 2 : 2,8

Should I add 2 other smaller engines ? such as EDF 55 ? or can it keep it 2 engines ?

Cheers
I have retracts which add a lot of extra weight. So I would say yours will weigh somewhere around 2.3-2.5. So 2:2.5 should be heaps of power.

I have 2 servos for the elevator. You can use 1 servo for the elevator if u like, but may need one of these- Full Direction Elevator arms 80x28x12mm from hobbycity and then you can use 1 servo. So 4 servos is fine. I just always get a few spares as they are pretty cheap.
"- Wires/connectors = +/- 200 Gr" -> this is good, remember to get enough servo extension leads for servos and ESC.
- 2 x Plush ESC = 240 Gr

>>> Why should I take 2 x 80 Amp ESC ? 2 x 40 Amp is not enough ? A brushless motor needs its own independent ESC and they have to be 80A each. A 64DF will pull anywhere between 40A and 65A at full throttle so if you have an ESC at 80A then your safe. A 40A ESC will burn straight away. If you have 2 motors than you need 2x ESC's. If you buy 2xESC's with BEC on each of them, then you must only use one BEC of the two ESC's. So you have to take off the red wire on the RX cable for one of the ESC's. Remember to buy a Y lead to connect the 2 ESC's to the Throttle channel of the RX

- 2 x EDF64mm Sapac Ducted Fan Unit w/4800kv Outrunner 3s 4s (2kg thrust) = 1100 Gr - This is an excellent FAN motor combination!! This is pretty much what I have except my motor is 4000kV. Be careful, make sure the motor is 4S capable and capable to handle 60+ Amps. The one you want (4800kV) will draw more Amps and produce more thrust at 4S. The 4000kV (my one) with 64mm fan draws 46A max. So my guess for the 4800kV the current draw may be 55A-60A. So your flight time will be less also for that battery pack. If you have 2x 4000mAH then I think you will still have enough power to make this plane fly. Remember to bench test your ducted fan, battery and ESC setup before you place it in the plane. Oh, one thing I just noticed on that ebay website "package Contents

* 100% Brand New
* Duct Fan Unit x1
* 4000kv outrunner brushless motor x1

So looks like its a 4000kv. So this seems to be the same as mine.
I got my fan and motor setup here locally in Australia and the shop I got it from no longer stocks the SAPAC motors, unfortunately. So if I need spare I'll go to the EBAY website you have shown me <- Thanks!!!!!


Should I add 2 other smaller engines ? such as EDF 55 ? or can it keep it 2 engines ? Too much cost and weight with 4 for not much benefit
There is a lot to learn in this hobby it's not simple I know. If you have further questions then keep asking me. It is important that you get all the right info before you buy otherwise the electronics will just not work.
KoziFlyer is offline Find More Posts by KoziFlyer
Last edited by KoziFlyer; Jan 15, 2010 at 11:09 PM.
Reply With Quote
Old Jan 16, 2010, 12:21 AM
Globemaster Maiden Time
KoziFlyer's Avatar
Melbourne
Joined Jun 2007
1,046 Posts
Hey Vicking,
Check out page 6 of this forum, post 81 -> my first video of the unpainted 747. This was stressful and it's first successful flight as a DF version.
KoziFlyer is offline Find More Posts by KoziFlyer
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Plug in removable wings for depron park jets ram3500-rcu Pusher Prop Jet Models 22 Feb 12, 2006 07:23 PM
Question Searching plan for depron impeller jet / Or building Steves f18 with an impeller??? German_wing Foamies (Kits) 1 Jan 24, 2005 08:34 AM
Question Plan for depron jet trainer RicoJ Electric Ducted Fan Jet Talk 5 Nov 03, 2004 02:09 AM
Missing wing ribs in Corsair plan... Please help. NetForce2K Parkflyers 1 May 09, 2003 09:12 PM
Need a plan converted from dwg to dxf dirtdiver Electric Plane Talk 1 Feb 27, 2003 09:12 PM