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View Full Version : How much weight can a Slow Stick Carry??


I_Love_My_ABC
11-02-2005, 02:25 PM
I was out at the park a few days ago with my digital camera hoping to get a few good in-flight shots of my Slow Stick when I realised that with my flight skill level I really should keep two hands on the TX at all times!! I decided to strap my camera under the plane and see if it would fly. The results were surprising...

http://media.putfile.com/First-Attempt-at-Arial-Video (http://media.putfile.com/First-Attempt-at-Arial-Video) (Click Here For Broadband Version)

http://media.putfile.com/First-Video-Flight-Small (http://media.putfile.com/First-Video-Flight-Small) (Click Here For Dial-Up Version)


...I don't think that I'll do this too many times as the camera is fairly heavy and I don't really want to replace a brushless ESC or motor due to a burn out!!

By the way, how dangerous is it for a Slow Stick to carry that much weight?? I'm running standard GWS micro radio gear, 4 Pico servos (2 x aileron in wings + 1 each for rudder and elevator) a Shuttle (BP-21) brushless outrunner, 18amp ESC, 900Mah 7 cell 8.4volt NiMh Hobbyzone flight pack with 9x47 prop hauling a Sony DSC-P72 digital camera (Approximately 270 grams in weight)

How many amps approximately would I be pulling with this setup?? It seems to climb out fairly easily and glides really well too.

:cool: :cool:

KarlB
11-02-2005, 09:48 PM
Nice video. Is the music by Joe Satriani? Sounds a bit like him, though I haven't heard that song before.

qban_flyer
11-02-2005, 10:01 PM
By the way, how dangerous is it for a Slow Stick to carry that much weight?? I'm running standard GWS micro radio gear, 4 Pico servos (2 x aileron in wings + 1 each for rudder and elevator) a Shuttle (BP-21) brushless outrunner, 18amp ESC, 900Mah 7 cell 8.4volt NiMh Hobbyzone flight pack with 9x47 prop hauling a Sony DSC-P72 digital camera (Approximately 270 grams in weight)


:cool: :cool:

The thing you really have to worry about is the wings! Those wings are not designed to carry that extra weight (9.47 oz) and you are risking the very real possibility they'll fold in half bringing the entire affair to the ground.

I haven't got a clue as to how expensive your camera is, though I am sure you wouldn't want to lose it in a crash.

flyranger
11-02-2005, 10:28 PM
Have you added any shipping tape to the wings?

I_Love_My_ABC
11-02-2005, 10:42 PM
Nice video. Is the music by Joe Satriani? Sounds a bit like him, though I haven't heard that song before.
Yes it is Satriani, nicely picked!! I actually saw him a few years back in Sydney... great gig too, a truly brilliant axe-man!! The track is called Always with me, always with you (Just in case you're looking for it....)

Oh, and qban, I was a bit worried about folding the wings too so I added a couple more CF rods to stiffen the wings a bit and 8 strong elastic bands instead of the 4 I usually use. I also strengthened them with packing tape flyranger, it does help a lot!!. Even after all that it still looked like the dihedral was about twice the normal angle in flight.

Like I said, I don't think I'll be doing that too often but it's a bit of a thrill knowing that you're only inches away from disaster!! You all know what they say..."No gut's no glory" I fear that in my case it's a matter of... "No common sense, no money left in the wallet" :( :(

I actually took it out this morning with the camera again and lost radio control. Spiral dived and hit the ground pretty hard semi nosed it in and caught the right wing. The walk of shame was as bad as ever... I thought I'd totalled the whole thing but to my absolute amazement NO DAMAGE!! The camera was still rolling too so I'll post that one soon, it's a pretty good laugh!! :p :D :p :D

I usually fly early in the mornings after night-shifts (Like this morning) It's definately not an ideal situation but I find that the wind is at it's lightest at that time. It's a big trade-off though as I'm pretty out of it after a 12 hour night-shift. It's kind of like trying to fly with severe jet-lag, which come to think of it probably explains why most of my mid-air-mishaps take place then!! Hmmm... I think there's something in that for all of us!!

ForestCam
11-02-2005, 11:55 PM
But can it carry a coconut like the African Swallow?
Maybe if you used to slow sticks togeather with the coconut a line.
:p

qban_flyer
11-03-2005, 02:22 AM
Oh, and qban, I was a bit worried about folding the wings too so I added a couple more CF rods to stiffen the wings a bit and 8 strong elastic bands instead of the 4 I usually use. I also strengthened them with packing tape flyranger, it does help a lot!!. Even after all that it still looked like the dihedral was about twice the normal angle in flight.

The wing is going to fold at the dihedral joint, and no amount of CF rods and tape is going to stop it from happening. Its weakest points are those two aluminum dihedral joiners, not just the foam.

The reason I am telling this is because I saw one behaving the same way with a cheap digital still camera onboard. Dihedral increased, wings began to "flap" slightly, then snapped the aluminum joiners and she fell to the ground. Plane was totalled but the camera survived and it is being used again for the same purpose on a modified SS.

If you must use the SS as a camera platform it may be wise for you to get the 'slope' version of it. The wing appears to be a bit thicker. I would then eliminate the dihedral and have a single 4mm CF tube glued to it at the CG. Having a single CF tube crossing the center and out toward the tips will add the strength needed for that payload carrying purpose.

Of course, having no dihedral will require that you use ailerons, but two HS-55s or GWS Picos should take care of that issue. Ailerons are already marked on the panels, just cut them out and use tape for hinges.

I_Love_My_ABC
11-03-2005, 03:20 AM
Thanks for the tips, it really helps to have guys like you that have seen or done it before. We get a chance to learn BEFORE bad things happen!! :cool:

Thanks again, I'll do that just as soon as I get to the LHS again. I've already done the aileron mod so I'm half way there. I will eventually get hold of a lighter camera setup. I'm becoming hooked on arial video!! It sure does give you a hell of a different perspective from way up there...

qban_flyer
11-03-2005, 05:38 AM
Thanks for the tips, it really helps to have guys like you that have seen or done it before. We get a chance to learn BEFORE bad things happen!! :cool:

Thanks again, I'll do that just as soon as I get to the LHS again. I've already done the aileron mod so I'm half way there. I will eventually get hold of a lighter camera setup. I'm becoming hooked on arial video!! It sure does give you a hell of a different perspective from way up there...

YUP! It is very addictive and so much fun to watch it, especially when the filming is done on calm days.

Do so on windy ones and you'll be reaching for the barf bag while watching the playback on a big screen!
:D :D :D

KarlB
11-03-2005, 02:17 PM
One big thing that can strengthen the center joint in the SS wing design is to rigidly join both panels along their upper surfaces. If you flex your wing up with your hands, you'll see the panels approach as the spar joints bend. Either bridge the gap with a thin ply or crossgrain balsa skin, or fill the gap. I did the latter, using a wedge of balsa sanded to fit, secured with polyurethane glue that expands to fill the voids.

This way, the spars provide tension, while the upper curve of the wing surface provides compressive strength. If all you have are the cheap aluminum joiners, or even a brass or steel tubing upgrade, they still aren't very strong. In unreinforced wings, it's the rubber bands securing the spars along the wing brackets that provide what little strength there is.

flyranger
11-03-2005, 02:34 PM
I cut out the stock "rib" in the center, allowing the wing to lay completely flat. Block sanded the edges to fit, then joined with 2.5 inch fiberglas cloth and 5 minute epoxy. I then probably went overkill and added carbon fiber rods in leading and trailing edges. Leading edge rod is joined with brass tubing with an inner diameter just slightly larger than the CF rod and glued with 5 minute epoxy. I made a slight indentation in the foam wing with a ballpoint pen and glued the rods in place with foam-safe CA. The stock wing was assembled with lots of shipping tape. Pics attached.

qban_flyer
11-03-2005, 05:08 PM
One big thing that can strengthen the center joint in the SS wing design is to rigidly join both panels along their upper surfaces. If you flex your wing up with your hands, you'll see the panels approach as the spar joints bend. Either bridge the gap with a thin ply or crossgrain balsa skin, or fill the gap. I did the latter, using a wedge of balsa sanded to fit, secured with polyurethane glue that expands to fill the voids.

This way, the spars provide tension, while the upper curve of the wing surface provides compressive strength. If all you have are the cheap aluminum joiners, or even a brass or steel tubing upgrade, they still aren't very strong. In unreinforced wings, it's the rubber bands securing the spars along the wing brackets that provide what little strength there is.

I sanded the center section of both panels, wiped them clean with alcohol, then used epoxy to keep them together. Mine flexes toward the tips, but not near the center joint.

qban_flyer
11-03-2005, 05:10 PM
I cut out the stock "rib" in the center, allowing the wing to lay completely flat. Block sanded the edges to fit, then joined with 2.5 inch fiberglas cloth and 5 minute epoxy. I then probably went overkill and added carbon fiber rods in leading and trailing edges. Leading edge rod is joined with brass tubing with an inner diameter just slightly larger than the CF rod and glued with 5 minute epoxy. I made a slight indentation in the foam wing with a ballpoint pen and glued the rods in place with foam-safe CA. The stock wing was assembled with lots of shipping tape. Pics attached.

Your first and second photos are worth a thousand words each. I'd be willing to bet your wing doesn't flex or flap.

TaSaJaRa
11-08-2005, 02:23 PM
I did 2 mods to the stock wing.

Carbon Fiber rod on the wing edge tied in from side to side above the jointer, then fiber glassed the center gap. My wing don't flex at all.

And if you like having ailerons on your slow stick you can build a wing from blucor as the one I did below.

Slow Stick Custom Wing (http://www.wattflyer.com/forums/showthread.php?t=222)
I also have an in flight video on the thread above.

And a Video from my Slow Stick in flight.
Click here to watch my First-Slow-Stick-AP-video (http://media.putfile.com/First-Slow-Stick-AP-video)

qban_flyer
11-08-2005, 04:27 PM
I like what you did with your Stick. Look really good. Have compared the weight of an original SS wing to yours? :confused:

TaSaJaRa
11-08-2005, 04:42 PM
Have compared the weight of an original SS wing to yours? :confused:
About 25.5 oz without battery. 30+ with battery and 35oz or so on the in flight video
with a 5mp camera. So it's maybe 18oz more than a stock slow stick.
But If you use a good brushless motor it will pull the weight fine.
All of my motors are from JustGoFly (http://justgofly.com/) I have a few of my planes and videos listed there.
I have one 3.5lb AP Plane listed here (http://justgofly.com/tech_450TH.htm)and it pulls real well with a 450TH from JustGoFly (http://justgofly.com/)
Later....

qban_flyer
11-08-2005, 05:07 PM
About 25.5 oz without battery. 30+ with battery and 35oz or so on the in flight video
with a 5mp camera. So it's maybe 18oz more than a stock slow stick.
But If you use a good brushless motor it will pull the weight fine.
All of my motors are from JustGoFly (http://justgofly.com/) I have a few of my planes and videos listed there.
I have one 3.5lb AP Plane listed here (http://justgofly.com/tech_450TH.htm)and it pulls real well with a 450TH from JustGoFly (http://justgofly.com/)
Later....

That's why it lands a bit faster than the stock one.:)