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Jan 23, 2018, 12:46 PM
Registered User
Nice design! I can see that we like similar lines 😎
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Jan 23, 2018, 03:21 PM
Fun fun fun.... bang
ScottySpoon's Avatar
Thread OP
very nice, how did she fly? I took my lines/curves from nature so i'm not surprised there many similar shaped craft,

As for the nose length thing.... this is the tricky bit, one major design aspect of this craft is testing a theory related to efficiency improvements based on a mathematical relation between the length of the nose and the sweep of the wing, i could increase nose a little without effecting this but realistically its far easier to bring the tail and center section trailing edge forward. another thing to conciser is she ain't going to be no DLG... the design is targeted at medium to heavy weight, it will most likely have the spar and a solid Dbox made from the blue/grey stuff. i did this on the latest RT30 i made and she is very strong, i also put a spar in the fin... .......

I've also changed the tail.... again....

Ill do some more fiddling and see what i can come up with
Jan 23, 2018, 05:46 PM
a wing is enough
Tail Saw's Avatar
That looks similar to the MiniRock:

Minirock am Felsen bei ~ 3 Bft (1 min 57 sec)


Minirock #5 lebt (1 min 36 sec)



I think your fin at the screenshot is much to small

Regards,

Uwe
Jan 23, 2018, 07:35 PM
Certifiable User
killercando's Avatar
Spooner, This project is gonna be great. Can't wait to get mine

Cool thing about the RT30 style plug in fin is you can optimize the shape and size for different weights and speeds.

Subscribed

Lee
Jan 23, 2018, 08:04 PM
Fun fun fun.... bang
ScottySpoon's Avatar
Thread OP
Quote:
Originally Posted by killercando
Spooner, This project is gonna be great. Can't wait to get mine

Cool thing about the RT30 style plug in fin is you can optimize the shape and size for different weights and speeds.

Subscribed

Lee
Yea i'm def gonna make it so i can change the fin later if needed, also it helps with transport... Heres where im at re fins (unblended yet)... however im changing body foil ... again and extending the nose/shortening the tail at the mo... will post some more pics when shes solid again
Jan 23, 2018, 09:06 PM
Registered User
Scott cool looking project
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Cheers Adam
Jan 23, 2018, 09:24 PM
More like crunchman....
dsman's Avatar
Experiences with Stab & a couple of Stab Elites (all 26" span) at various build/flying weights indicated these slippery little types don't need much mass to go fast, and it's easy to build too heavy resulting in both reducing flying opportunities & sluggish handling.

Perhaps nose as long as you can make it within your chosen design constraint, fin a tad bigger (relatively light lay-up is likely to provide adequate stiffness for all speeds) on a shorter/sturdier tail per Daemon's suggestion & ideally the only ballast being that needed in the nose to obtain CG, given lead ballast is a complete waste when a corresponding mass can be used to stiffen/strengthen the build.

Am a fan of a semi-counterbalanced fin, though they probably don't look as pretty & a rigid under-fin does have the minor disadvantage of pushing the nose toward the deck during landing touchdowns - the M60's was a push fit which rotated up out of the way on landing contact.
Jan 23, 2018, 09:57 PM
David Vels
Larrikin's Avatar
Scotty, I know you haven't asked for opinions ... so here's mine.

I still like your original design.
All I've done is removed the "stinger" (easier to build) and put a curve in the trailing edge, shark-fin style.
Also, I agree with lengthening the nose as much as you dare. The Rubicon's nose weight can = 7 - 8% of the total weight.
Grist for the mill.
D.
Jan 23, 2018, 11:20 PM
Fun fun fun.... bang
ScottySpoon's Avatar
Thread OP
While everyone was standing round with their pants down and rulers out.... i scrapped the first cad model and drew a complete new one lol with a longer nose, faster foil and some other tweaks, haven't finished yet but its looking better tail is still a bit small but ill finish that later
Jan 23, 2018, 11:25 PM
Fun fun fun.... bang
ScottySpoon's Avatar
Thread OP
Quote:
Originally Posted by Larrikin
Scotty, I know you haven't asked for opinions ... so here's mine.

I still like your original design.
All I've done is removed the "stinger" (easier to build) and put a curve in the trailing edge, shark-fin style.
Also, I agree with lengthening the nose as much as you dare. The Rubicon's nose weight can = 7 - 8% of the total weight.
Grist for the mill.
D.
I still like your original design .... Thunderbirds are goooooo!!!!!!!!
Jan 24, 2018, 12:41 AM
A geriatric flier
If it flies as well as Kiwi designed Americas Cup boats sail you will have a winner. Good luck.
Jan 24, 2018, 12:51 AM
Registered User
I have not flown it yet, still working on the fin and the radio gear. The fin is larger than on the screen shot. There I just put something as a placeholder while designing the wing shape.


Quote:
Originally Posted by ScottySpoon
very nice, how did she fly? I took my lines/curves from nature so i'm not surprised there many similar shaped craft,

As for the nose length thing.... this is the tricky bit, one major design aspect of this craft is testing a theory related to efficiency improvements based on a mathematical relation between the length of the nose and the sweep of the wing, i could increase nose a little without effecting this but realistically its far easier to bring the tail and center section trailing edge forward. another thing to conciser is she ain't going to be no DLG... the design is targeted at medium to heavy weight, it will most likely have the spar and a solid Dbox made from the blue/grey stuff. i did this on the latest RT30 i made and she is very strong, i also put a spar in the fin... .......

I've also changed the tail.... again....

Ill do some more fiddling and see what i can come up with
Jan 24, 2018, 01:35 AM
Fun fun fun.... bang
ScottySpoon's Avatar
Thread OP
Quote:
Originally Posted by Watdazit
If it flies as well as Kiwi designed Americas Cup boats sail you will have a winner. Good luck.
Funny cause the spread tow carbon I use is left over from the America’s cup boats.... for extra speeds
Jan 24, 2018, 03:51 AM
David Vels
Larrikin's Avatar
Quote:
Originally Posted by ScottySpoon
faster foil and some other tweaks,
Ok ... spill it? What are you using. Student minds neeeeed to know
Jan 24, 2018, 04:02 AM
A geriatric flier
Quote:
Originally Posted by ScottySpoon
Funny cause the spread tow carbon I use is left over from the America’s cup boats.... for extra speeds
Arhh that being the case, put some floats on it and then in any sort of breeze it will fly!


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