I think if I had put the clay at the front of the rocket, the wing would've opened. If it had, who knows where it would've spiraled to since it was heading toward the swimming pool. I'll rebuild and try again in July when we have a bigger field.
Semroc Scissor Wing Transport Kit Build Thread
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Aeronerd
LPR, Gliderholic
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Did the pop pod eject? If not, wings wouldnt have swung open.
Difficult to see in video but it did.
I see some paint on the pivot . . . Maybe it interfered with deployment ?
Dave F.
I masked the part that were contacting the pivot. The part with paint was on the backside. I think it was the clay on the back of the wing that caused the problem. I pieced the pivot together but missing the tabs.
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I can trace the pivot plate and missing tabs for you. The plate is 1/16" basswood and the tabs are 1/8" basswood. Should be easy to fabricate the missing parts.
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Conditions for painting haven't been ideal: far too hot, extremely humid, or both. I was only able to find a small window of opportunity a few days ago and hit the glider with the base white. The nose cone will stay unpainted until the glider has been trimmed out (it'll likely get bashed some and need some patching) and any nose weight added if needed. Then I'll glue it in and fill the BT/NC joint till there isn't one before painting.
The weather for hand trimming has been dismal—nothing but double-digit wind days and/or rain. Hopefully that will change soon so I can maiden it and do any final trimming before adding the decals.
The weather for hand trimming has been dismal—nothing but double-digit wind days and/or rain. Hopefully that will change soon so I can maiden it and do any final trimming before adding the decals.
Mine hasn’t earned its decals yet. What’s your plan for adding weight to the NC? I took about 10g of clay and glued it to the backside of the Balsa cone. Hopefully it stays there.
I’ll try another glide test this Sunday. Or maybe I’ll say eff it and launch again. If it lands in the canal, so be it.
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If it doesn't need a whole lot of weight I was going to glue a cardboard disc to the end of the nose cone shoulder and attach self-adhesive lead strips or clay to that and cover with thick CA. If more than just a few grams of weight are needed, I'll hollow out the shoulder and insert some small lead fishing weights I have.
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It spiraled in today so I’ll need to take half the weight out of the NC. No damage except the stuffer tube bent a little. Easy to fix. My repairs to the pivot mostly worked. I’ll take your offer for replacement parts.
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Hey Ron, when you said it "spiraled in", did you mean it glided down, but in a tight spiral? Or the wings didn't deploy and it spiraled down ballistically?
Eric,
I had the same questions and was about to post them, but you beat me to it.
Dave F.
Tight spiral down. Video will be ready soon.
I wrapped tape and strengthened with thin CA. I’m wondering if it needs tooth picks.
As I suspected might happen, without dihedral . . .
ERIC,
What do you think about the possibility of using "Stab Tilt" to induce a turn, instead of weight on a wing tip ?
Of course, lacking dihedral, the result might be the same ( a "spiral" ).
I'm thinking that modifying the Rudder to "activate", when the pod ejects, might produce a gentle, flat turn, without it "falling off on a wing tip".
Thoughts ?
Dave F.
ERIC,
What do you think about the possibility of using "Stab Tilt" to induce a turn, instead of weight on a wing tip ?
Of course, lacking dihedral, the result might be the same ( a "spiral" ).
I'm thinking that modifying the Rudder to "activate", when the pod ejects, might produce a gentle, flat turn, without it "falling off on a wing tip".
Thoughts ?
Dave F.
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Good idea about the toothpick reinforcement. Couldn't hurt, the miniscule amount of extra weight will get kicked out with the pod anyway.
I spent 45 minutes today hand-tossing the SWT to trim it. VERY difficult to get a nice level glide out of the thing. I got it to the point where it would stay about 2° to 3° nose-up for about 15 feet before taking a slight (about 3°) nose-down attitude. I was standing on a 6' hill so it covered about 30' in total without pitching down any more. Kind of a horrible sink rate but at least it DOES glide...sorta.
I DID sand a tiny bit more angle into the flap stop so I could take some tail weight off. No nose weight needed. My current CG is 8 5/8" from the rear of the body tube, interestingly just 1/8" off from the aft range of Estes' recommended CG point of 8.75" (see post #100). Off course no telling how it’s going to behave once launched, this bird is so unpredictable.
I think it earned its decals. I have more B6-2 on the way. Don’t think I’ll go bigger than that.
The ejection tube landed 2 feet from me yesterday. I’m having tendering issues but here’s the part from my live stream.
The ejection tube landed 2 feet from me yesterday. I’m having tendering issues but here’s the part from my live stream.
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How was the glide? Any flight footage?? 
I like gliders that stay in the park rather than high-performance ones that go permanently AWOL.
I like gliders that stay in the park rather than high-performance ones that go permanently AWOL.
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Not worth the effort with the rudder IMO. Adding further complexity to a design already struggling with complexity and reliability issues wouldn't be a good idea.
Stab tilt may work if kept to a modest 2° or so. That said, clay on a wingtip is adjustable. Just need the barest amount to induce a shallow turn; if too much, it can easily be scraped off.
How was the glide? Any flight footage??
I like gliders that stay in the park rather than high-performance ones that go permanently AWOL.
That was NOT a "spiral glide" . . . That was a vertical "death dive", with axial rotation.
Personally, I think the Glide CG is WAY too far forward. Perhaps, the Elevator is not activating or the elastic is too weak, causing it to "collapse" during flight ?
Dave F.
Personally, I think the Glide CG is WAY too far forward. Perhaps, the Elevator is not activating or the elastic is too weak, causing it to "collapse" during flight ?
Dave F.
It landed better than the last time, so I call that a win.
I compare it to my first flight that ended up in a rapid disassembly.
I compared those two videos, with a relatively flat glide, to the "death dive" in your video. It's pretty obvious that your CG is too far forward.
Dave F.
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Here’s another important caveat: offset the rudder so that its front edge is on one side of the centerline mark drawn on your Upper Nacelle tube, and its rear edge is on the opposite side. This is actually called out in step 30 of the SWT instruction sheet. Be conservative — a degree or so is more than enough.
DO THIS INSTEAD OF ADDING CLAY TO ONE OF THE WINGTIPS TO MAKE YOUR SWT CIRCLE.
Why? My suspicion is that adding just a tiny bit too much clay could push it over into a death spiral. Lacking any dihedral, I believe the glider is just barely stable as it is, so forcing one wing to drop lower to make it turn is probably not a good idea under the circumstances. This realization comes a bit too late for me — I forgot this step and glued my rudder on straight.
DO THIS INSTEAD OF ADDING CLAY TO ONE OF THE WINGTIPS TO MAKE YOUR SWT CIRCLE.
Why? My suspicion is that adding just a tiny bit too much clay could push it over into a death spiral. Lacking any dihedral, I believe the glider is just barely stable as it is, so forcing one wing to drop lower to make it turn is probably not a good idea under the circumstances. This realization comes a bit too late for me — I forgot this step and glued my rudder on straight.
Agreed. I took it most of the clay. I wanted took try it again on Sunday but only had B6-4.
Eric,Lacking any dihedral, I believe the glider is just barely stable as it is, so forcing one wing to drop lower to make it turn is probably not a good idea under the circumstances. This realization comes a bit too late for me — I forgot this step and glued my rudder on straight.
A possible "fix" . . . Glue a vertical strip to one side of the Rudder. It should create enough aerodynamic force to generate a "flat turn", but you will have to experiment, as to size of the strip.
Thoughts ?
Dave F.
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Had the same idea as the only alternative and already installed a "Gurney Flap". Just waiting for a calm day to do some trimming tosses.
Hopefully, that modification will solve the situation . . . Fingers crossed for success !
Dave F.
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