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Old Sep 07, 2014, 05:10 PM
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I know its ugly but Wow

I started on a Sig 2M Riser kit but i was really worried that my small rough flying field would just be to small for a 2 meter glider like this, all my previous gliders have been home made foamy s with much shorter wing spans. at any rate i thought i would build a quick foamy with all the same measurements as the Sig kit so if all went bad i would not be out of a lot lol, well i took the foamy out this early am and Wow , what a great slow flying glider . i could slow it down to a craw to line up for my landings with no trouble at all. Makes me think all my previous work building smaller gliders was in vane that bigger is much better. now i really have to get going on the balsa kit lol.
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Old Sep 07, 2014, 05:33 PM
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United States, PA, Canonsburg
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Larry, That thing ain't THAT bad!!! I haven't seen a foamy that would win a beauty contest yet!! From 200 feet I bet it looks just like the one you copied!! Show us some detailed pictures of how it is constructed. You said it flies well, that is what counts!! Good Job!! Jeff Little
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Old Sep 07, 2014, 05:56 PM
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The wing is just hot wired foam using traced Sig Riser rib as the template to make a couple of thin ply guides to cut the wing. The body of the fuse is 1/2 inch blue foam covered on both sides with 1/8 fan fold foam to give strength and glued with gorilla glue. The Tail feathers are also 1/8 fan fold foam and i glued in a carbon spar don the middle of the stab. just a simple build..
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Old Sep 07, 2014, 08:07 PM
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The Riser is a good model, but I think slightly larger is better, even on a small field. It's more about wing loading than it is about span, until you get to a turn so tight that the inside tip is going much slower than the outside one. I expect a light Oly II would out float the Riser and be a little more pleasant to fly, as well as more visible when you catch a thermal and end up at 1,000 or 2,000 feet. I haven't flown the 100 inch Riser, so I don't know if it's comparable.

However, if you do build a 2M Riser, I'm sure you'll like it.
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Old Sep 07, 2014, 09:17 PM
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Nice work, I see epoxy and a vacuum bag in your future

Dave
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Old Sep 07, 2014, 09:32 PM
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Thanks Dave , That is for sure one thing on my must learn how to do list, only wish i knew some one who does that kind of work i could shadow for a day or two lol. i see a lot of good work in the hand launch forum .
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Old Sep 08, 2014, 08:43 AM
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Athens, LA, United States
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For me it seems that 2m to 100" is the sweet spot for me. Since I fly alone, a lonnnggg wingspan is a bit much to handle in a breeze (launch prep) and that size just seems to "fit" my needs best. I've actually spent a lot of time in the air with a Spirit and a standard class Aquila.

EJ
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Old Sep 08, 2014, 03:14 PM
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United States, MD, Towson
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that sig wanna- bee looks great! now put down the foam and get going on that wood kit my friend. you will love it! i do. that way you have 2 great flying models. add the spoilers as i did on recommendation from folks here. glad i did they work amazing. have fun. Walt p.s. i fly my riser 2m at 2 ball fields back to back plus some extra field and with spoilers i can drop her anywhere.
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Old Sep 08, 2014, 03:28 PM
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Thanks Walter , if you have time could you post a couple of close up pics to how your an spoilers work , i am still a little fuzzy on how to do them but i guess just a servo arm can deploy them with no formal linkage ?? Yes it sure does seem that the sweet spot for gliders is in the 78 thru 100 inch wing span huh, my smaller winged foamy s is headed to the trash heap no dough lol. ..
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Old Sep 09, 2014, 02:53 AM
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The "sweet spot" for gliders depends on a lot of factors. If you have a really clean design, a DLG at only 1.5 meters flies very well and is a whole lot easier to launch than something larger. (I've actually DLG launched an Ava, with the help of some rope, but I don't think I broke 50 feet, I had to make several spins, and it pulled very hard.

For goal and return, my guess is that the "sweet spot" might be between 4 and 5 meters. For TD, 3 meters isn't bad, though some people are going to 4.

If you do a search on RC Groups, you'll find quite a bit of discussion of spoilers. There's even a drawing by me of how to do a torsion bar spoiler spring, which is very easy. Possibly other drawings. But I don't know just where they appeared.
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Old Sep 09, 2014, 12:24 PM
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Napa, California
Joined Jul 2006
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Hi Larry,

Great project here!

Just my 2 cents on spoilers, and there are many ways of doing this, I just have the servo arm push open the spoiler and use a small magnet attached to the underside of the spoiler blade to help keep it closed. In the spoiler bay, I locate a small piece of wood somewhere convenient, "lower" in the bay so the magnet doesn't touch it when closed. I then screw a very small (light) screw into the piece of wood so that the head of it acts as the attracting surface to the magnet. For adjustment/ tension, simply adjust the screw in/out.

Sorry, no pics, but I'll see about take one later if you like?

Cheers,

Rob
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Old Sep 09, 2014, 01:09 PM
I just want to go fly!
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if you go to the Sig riser 2m build forum you will see some nice pics of spoilers. those are some of the ones i used as well. google rc sailplane spoiler images and you will find lots to guide you. i just used the ultra coat as hinge and servo arm with a bit of wood extension glued to it to push up the spoiler. when reversed it just falls with gravity shut. works great! cant imagine struggling to spot land without them. well worth the tinkering IMHO. good luck. Walt
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Old Sep 09, 2014, 02:27 PM
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Thanks for the help on the spoilers, i think i got the concept down now lol. just do a little tinkering and ill have it...cheers
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Old Sep 10, 2014, 05:43 PM
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Here's one way to do it, although I haven't done it this way yet:
http://www.stevensaero.com/downloads...d=19699&dlid=5
Looks pretty good except that I'd have the spring between the spoiler and the wing so that the servo has no load when closed.

___________
I've also set up spoilers the way Rob describes. You can adjust the power of the magnets by using different shaped screw heads. A flat head, at least if the magnet is aligned with it, pulls the strongest. A pan head ought to be a little weaker and a round head weaker than that. You could also put a bit of tape or something on the magnet to adjust the force.

---------------
Here's a simplified picture of a torque rod to pull down the spoiler. It would only have to be strong enough to get the spoiler in range of the magnets. The smaller the length, the smaller the wire you can use. Like maybe in the range of steel guitar string sizes, well under 1/32". You just bend the wire, slip two tubes over the short ends, and glue them in place. The wire should be bent as if the spoiler was to be angling below the surface of the wing. Then, when the spoiler is above the surface of the wing, it will try to twist back down. I
http://www.rcgroups.com/forums/showp...20&postcount=8
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Old Sep 10, 2014, 06:49 PM
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Looks Great Lincoln, thanks for the link and the torsion spring idea. nice simple way to do it... i have lots to learn in the sailplane world and this forum is just the ticket
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