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Feb 08, 2015, 04:34 PM
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Originally Posted by theskyiscrying
Balsa or Carbon, how do you mount the motor to the wing?
If your motor is already attached to a wood firewall , you can do it like this :

Build a structure out of scrap foam board ; the sides are two right triangles , the top is one rectangle . Glue the firewall to the 90* vertical end of the structure , then glue the whole thing on top of the wing so the PROP IS STRAIGHT AND CENTERED in the prop slot . Then I also tape the structure down with some packing tape .

Al
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Feb 19, 2015, 02:33 PM
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I'm bringing my interest over to this thread from the Discussion Scratch Built Dollar Tree Foam Planes thread to learn more about this simple flying wing.

How was your CG determined? I'm using a couple of online flying wing calculators, but I'm getting different results. I'm also hoping that I don't have too much motor or battery for this simple wing design. This is what I'm using along with a Spektrum AR610 RX and two HXT900 servos. I am using the components from my failed Polaris Seaplane build until I begin another Polaris build.

EDIT;
Never mind, I re-read your first post and determined the approximate location of the CG and the motor.
Last edited by Robert4613; Feb 19, 2015 at 02:55 PM.
Feb 19, 2015, 03:19 PM
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Quote:
Originally Posted by Robert4613
I'm bringing my interest over to this thread from the Discussion Scratch Built Dollar Tree Foam Planes thread to learn more about this simple flying wing.

How was your CG determined? I'm using a couple of online flying wing calculators, but I'm getting different results. I'm also hoping that I don't have too much motor or battery for this simple wing design. This is what I'm using along with a Spektrum AR610 RX and two HXT900 servos. I am using the components from my failed Polaris Seaplane build until I begin another Polaris build.
Do you have any lighter batteries than that 2200mah ? I think the simple delta would be fine with those electronics and an 800mah - 1000mah battery . If you only have a 2200mah , you could scale up the simple delta by butt joining two sheets of DTFB together ( photo below ) . That will give you a larger airframe to keep the wing loading low .

I determined the CG by having built LOTS of deltas over the years and learned early on that 40% is a good starting point . A lower aspect ratio delta such as this one isn't as pitch sensitive as a higher aspect ratio flying wing , but the " bank and yank " flying characteristics are similar enough to make it a good practice plane .
Feb 19, 2015, 03:51 PM
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Quote:
QUOTE=balsa or carbon;30835878]Do you have any lighter batteries than that 2200mah ? I think the simple delta would be fine with those electronics and an 800mah - 1000mah battery . If you only have a 2200mah , you could scale up the simple delta by butt joining two sheets of DTFB together ( photo below ) . That will give you a larger airframe to keep the wing loading low .
Unfortunately, no. I only have the 2200 mAh and the Apprentice' 3200 mAh. I probably will need to get me another battery in the size range that you've suggested, once the bills have been paid. Maybe I'll go ahead and build the scaled-up version to accommodate that battery for the meantime.

Once again, thank you for your help. I'll let you know how this all turns out.
Feb 19, 2015, 04:06 PM
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Quote:
Originally Posted by Robert4613
Unfortunately, no. I only have the 2200 mAh and the Apprentice' 3200 mAh. I probably will need to get me another battery in the size range that you've suggested, once the bills have been paid. Maybe I'll go ahead and build the scaled-up version to accommodate that battery for the meantime.

Once again, thank you for your help. I'll let you know how this all turns out.
The scaled up ( 40" wingspan ) version should be a nice floater with that light wing loading , and will probably also have a gentle roll due to the larger wingspan/wing area - making it easier to control ( no sudden corkscrews ! ) . For the maiden flight , start with both elevons SLIGHTLY up for reflex ; then adjust the battery forward/rearward as needed for a good flight attitude .

Al
Feb 19, 2015, 04:24 PM
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Originally Posted by balsa or carbon
The scaled up ( 40" wingspan ) version should be a nice floater with that light wing loading , and will probably also have a gentle roll due to the larger wingspan/wing area - making it easier to control ( no sudden corkscrews ! ) . For the maiden flight , start with both elevons SLIGHTLY up for reflex ; then adjust the battery forward/rearward as needed for a good flight attitude .

Al
I'll give this a try. Thanks.
Feb 19, 2015, 05:20 PM
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Originally Posted by Robert4613
I'll give this a try. Thanks.
I have some electronics in need of a plane , so I'm going to build a large one myself !

Al
Feb 19, 2015, 07:51 PM
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Originally Posted by balsa or carbon
I have some electronics in need of a plane , so I'm going to build a large one myself !

Al
I have a plane that is in need of electronics, but these are big ones for a 7 lb. 12 oz. balsa and plywood. I wonder how well that my Apprentice AS3X RX will work in there?

I was going to break out my DTF stash, but due to a rather sudden plumbing emergency at my house (teen boy washed his grandfathers truck and pulled the faucet out of the wall) I had to deviate from plan and take care of that. Oh well, the joys of owning a home.
Feb 19, 2015, 11:07 PM
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Here's my BIG one , we'll see how it flies tomorrow if the weather allows .
Feb 20, 2015, 07:55 AM
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Originally Posted by balsa or carbon
Here's my BIG one , we'll see how it flies tomorrow if the weather allows .
Looks good! It looks like that you'll have no problem with it.
Feb 20, 2015, 11:21 AM
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The BIG ONE flew beautifully - very smooth and stable ! Cruised around slow and easy at less than half throttle , and had a lot of zip at full throttle . I'll shoot a video tomorrow AM when I'm flying with a buddy .

It balanced perfect with a 2200mah 3S , and has this 360 watt 1880kv motor .
Feb 20, 2015, 12:33 PM
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Quote:
Originally Posted by balsa or carbon
The BIG ONE flew beautifully - very smooth and stable ! Cruised around slow and easy at less than half throttle , and had a lot of zip at full throttle . I'll shoot a video tomorrow AM when I'm flying with a buddy .

It balanced perfect with a 2200mah 3S , and has this 360 watt 1880kv motor .
That's great news! Looks like that I'll have to build mine tomorrow and see how well that it does.
Feb 21, 2015, 12:19 PM
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Here's the video from this morning :
Giant simple delta (2 min 0 sec)
Last edited by balsa or carbon; Feb 21, 2015 at 01:03 PM.
Feb 21, 2015, 12:51 PM
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Quote:
Originally Posted by balsa or carbon
Do you have any lighter batteries than that 2200mah ? I think the simple delta would be fine with those electronics and an 800mah - 1000mah battery . If you only have a 2200mah , you could scale up the simple delta by butt joining two sheets of DTFB together ( photo below ) . That will give you a larger airframe to keep the wing loading low .

I determined the CG by having built LOTS of deltas over the years and learned early on that 40% is a good starting point . A lower aspect ratio delta such as this one isn't as pitch sensitive as a higher aspect ratio flying wing , but the " bank and yank " flying characteristics are similar enough to make it a good practice plane .
Quote:
Originally Posted by Robert4613
Unfortunately, no. I only have the 2200 mAh and the Apprentice' 3200 mAh. I probably will need to get me another battery in the size range that you've suggested, once the bills have been paid. Maybe I'll go ahead and build the scaled-up version to accommodate that battery for the meantime.

Once again, thank you for your help. I'll let you know how this all turns out.
It seems that I was mistaken. Last night, while gathering up all of my components to solder on the EC3 battery connectors and the bullet connectors for my motors, I had discovered that I had two 20C 3S 1600 mAh batteries that I had gotten for my 60" OF-ish. I had forgotten that I had those. Now that since all of my batteries share the same EC3 terminals I can mix and match as needed, depending on the aircraft purpose, size and weight.
Feb 21, 2015, 12:56 PM
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Quote:
Originally Posted by balsa or carbon
Here's the video from this morning :
https://www.youtube.com/watch?v=llrhpzCmdcU
It looks like that it was a good flight.


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