Anybody else scratch building tonight?

Vimana89

Legendary member
So you put canards on your plank plane? Do you have any pics?
Yeah posted it at another time but could dig them out and repost. That thing flew aweful but it could have been more technical stuff like thrust angle or something else off. Like I said, all it did was turn left, which lead to the wind taking it when I maidened in high winds. I found it again but didn't figure out the issue till further testing. Didn't stop me from doing touch and go circuits and skid launching off the belly until I really busted the nose again...so now, regular plank😆.
 

BATTLEAXE

Legendary member
Yeah posted it at another time but could dig them out and repost. That thing flew aweful but it could have been more technical stuff like thrust angle or something else off. Like I said, all it did was turn left, which lead to the wind taking it when I maidened in high winds. I found it again but didn't figure out the issue till further testing. Didn't stop me from doing touch and go circuits and skid launching off the belly until I really busted the nose again...so now, regular plank😆.
I was wondering how it worked out cuz a quick idea came into my head for this 130% Goblin that is so heavy I am hesitant to maiden it. What if I traded a little nose weight into some lifting surface on the nose to help keep the nose up at slower speeds by putting canards in the front? If I did how much effect would they have? It would kinda be like the Long EZ in concept I am thinking. Thoughts?
 

Grifflyer

WWII fanatic
I was wondering how it worked out cuz a quick idea came into my head for this 130% Goblin that is so heavy I am hesitant to maiden it. What if I traded a little nose weight into some lifting surface on the nose to help keep the nose up at slower speeds by putting canards in the front? If I did how much effect would they have? It would kinda be like the Long EZ in concept I am thinking. Thoughts?
I think if you put canards on planes you'd need the CG even farther forward to get it to fly correctly, but don't quote me on this...
 

L Edge

Master member
I was wondering how it worked out cuz a quick idea came into my head for this 130% Goblin that is so heavy I am hesitant to maiden it. What if I traded a little nose weight into some lifting surface on the nose to help keep the nose up at slower speeds by putting canards in the front? If I did how much effect would they have? It would kinda be like the Long EZ in concept I am thinking. Thoughts?

Can you show me a picture of what you got?
 

BATTLEAXE

Legendary member
Can you show me a picture of what you got?
It's a Goblin just bigger
20191204_191802.jpg
20191204_191829.jpg

Has a 3536 1200Kv off the back on a 9x6 APC sport prop. To get it to balance on CG it needs the equivalent weight of just over three 2200 3s batteries right up in the front and has a AUW of maybe 2kg's or more. If it was a tractor I could save a ton of weight plus get the benefit of prop wash over the wing, but that would kind of take away from the onboard cam/FPV options I intend to use it for
 

BATTLEAXE

Legendary member
I don't know if it all counts as scratch building but I've been trying to get flyable airframes ready for the long NY weekend. Minor to major repairs on several planes, trying to finish that Explorer that has sat way too long, Maybe finish a second FT-3d, and working on doing an Arrowhead.
How do you like the FT-3D, probably enough to build a second one lol. Do you have any pics or vids on the first one?
 

L Edge

Master member
It's a Goblin just bigger View attachment 150985 View attachment 150986
Has a 3536 1200Kv off the back on a 9x6 APC sport prop. To get it to balance on CG it needs the equivalent weight of just over three 2200 3s batteries right up in the front and has a AUW of maybe 2kg's or more. If it was a tractor I could save a ton of weight plus get the benefit of prop wash over the wing, but that would kind of take away from the onboard cam/FPV options I intend to use it for

Are you looking for speed or just want it to work?
 

mayan

Legendary member
I was wondering how it worked out cuz a quick idea came into my head for this 130% Goblin that is so heavy I am hesitant to maiden it. What if I traded a little nose weight into some lifting surface on the nose to help keep the nose up at slower speeds by putting canards in the front? If I did how much effect would they have? It would kinda be like the Long EZ in concept I am thinking. Thoughts?
I like it.

@L Edge come on you got this, take care of @BATTLEAXE he needs help and you have the knowledge :).
 

BATTLEAXE

Legendary member
Are you looking for speed or just want it to work?
As it sits I am thinking it is gonna need a Warren Moon power kind of hand toss just to get it airborne and will take a lot of speed to get it to stay up. I know the wing is close to the same surface area of the Sportster but much heavier. The Sportster flew well and could glide nice and could carry some decent weight, but it also had prop wash. Going fast isn't a priority because I know it has fast potential judging by the stock size. I haven't maidened it yet so I don't know how exactly it will react, just speculation so far. If I had confidence that it would work then yea that would be a good start. I appreciate the help if you have any ideas
 

L Edge

Master member
As it sits I am thinking it is gonna need a Warren Moon power kind of hand toss just to get it airborne and will take a lot of speed to get it to stay up. I know the wing is close to the same surface area of the Sportster but much heavier. The Sportster flew well and could glide nice and could carry some decent weight, but it also had prop wash. Going fast isn't a priority because I know it has fast potential judging by the stock size. I haven't maidened it yet so I don't know how exactly it will react, just speculation so far. If I had confidence that it would work then yea that would be a good start. I appreciate the help if you have any ideas

If you were going fast, don't have a solution. Might have something in mind, give me some time. Might have a solution.
 

Flying Monkey fab

Elite member
How do you like the FT-3D, probably enough to build a second one lol. Do you have any pics or vids on the first one?
I like it, #1 survives but I know it won't for long! On madden, I could not get it into trim in time to not crash but little damage to it. Nothing special about it, I'll post pics when I build one that I think will survive a few months. LOL 😂
 

BATTLEAXE

Legendary member
If you were going fast, don't have a solution. Might have something in mind, give me some time. Might have a solution.
@Headbang did mention to extend the weight out off the nose on a stick to get the weight down by way of leverage just to try it. I don't mind extending the nose even by a few inches which may get the AUW down. Then I just came across this canards idea... I will wait to see what you got cooking up
 

Vimana89

Legendary member
Man this thread got poppin' when I was at work. Scratch built airfoils, straight wings, and canards are all pretty new to me and that bird I built had all three, so no wonder I got a lot wrong. @BATTLEAXE the one thing I did take out of it is that as a rule of thumb for a lot of canard setups, you do want the CG super far forward on the main wing, like barely back at all or right on the leading edge. It's gonna be in the first 5-15% or so as far as I know.
 

Vimana89

Legendary member
I don't know if it all counts as scratch building but I've been trying to get flyable airframes ready for the long NY weekend. Minor to major repairs on several planes, trying to finish that Explorer that has sat way too long, Maybe finish a second FT-3d, and working on doing an Arrowhead.
Maintenance work is definitely necessary now and then. Repairing,reinforcing, checking servos,even replacing something or remounting a loosening motor...all that is important stuff. I know that now that my planes last more than a few seconds😆. Speaking of which, I'm stoked to hear about the Arrowhead👍. Can't wait to see how that turns out!
 

BATTLEAXE

Legendary member
Man this thread got poppin' when I was at work. Scratch built airfoils, straight wings, and canards are all pretty new to me and that bird I built had all three, so no wonder I got a lot wrong. @BATTLEAXE the one thing I did take out of it is that as a rule of thumb for a lot of canard setups, you do want the CG super far forward on the main wing, like barely back at all or right on the leading edge. It's gonna be in the first 5-15% or so as far as I know.
The CG marks are already at the 10% point already
20191202_181746.jpg

See the little white dot at the wing root just under the LE, that's it. That's where I have been balancing to. Mind you everyone who has maidened theirs has said they have moved the CG back, which if I did it would lighten up considerably