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Semroc - Swift BG

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JAL3

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Where did you get that clamp?
It was part of a pair I bought in a hobby shop called HobbyTown USA. I think its a national chain but am not sure.

If you like, I'll check for any labeling on it when I get back over there.
 

TheAviator

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Even though I knew I was doomed by this point, I figured I had gone too far to back out now and I got to work on the pod hook. It was in two pieces which needed only to be glued together. I used white glue and clamped it.
There's no way that you are doomed. Every single one of my gliders has surfaces aligned with the good ol' Mark I Eyeball. You would be surprised how tolerant these gliders are to slight misalignments. In trimming, some people even build them in! (A little twist of the rudder for turning, a little twist up of the elevator for glide trim.)
 

JAL3

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There's no way that you are doomed. Every single one of my gliders has surfaces aligned with the good ol' Mark I Eyeball. You would be surprised how tolerant these gliders are to slight misalignments. In trimming, some people even build them in! (A little twist of the rudder for turning, a little twist up of the elevator for glide trim.)
Its not so much the eyeball that dooms me. Its the glider part. Gliders don't like me although...this project is looking up. I just haven't had the chance to give the details yet and I'm looking for the right cable to transfer the vid!
 

JAL3

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The first step in working on the engine pod was to take the motor spacer and mark off 1/4".

SBG-mm-1.jpg
 

JAL3

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The thrust ring was then located and the Kevlar was tied around it.

SBG-mm-2.jpg
 

JAL3

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A ring of white glue was swabbed around the interior of the motor tube, using the motor spacer to mark the swab at the right depth. The spacer was then used to push the thrust ring into place, up to the mark which had been made, and withdrawn.

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JAL3

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The motor tube was then marked for the placement of the engine hook and a slit was made in the body tube to receive it.

SBG-mm-6.jpg
 

JAL3

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The hook was placed and a cardboard sleeve was slipped into place to hold it in place.

Shortly after I began this build, Sheryl from Semroc contacted me and let me know that in some of these kits, the band was too tight and gave advice of fixing the problem. Mine was just a touch tight but, in my mind, well within tolerances. It was glued in place with white glue and filleted fore and aft.

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JAL3

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The nose cone was typical, high quality Semroc. I doused it with some thin CA to harden it up some.

SBG-nc-1.jpg


SBG-nc-2.jpg
 

JAL3

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I turned my attention back to the glider again. As far as I could tell by looking at it, it was in pretty good shape. The intersections needed some filleting and I tried using Titebond Trim and Molding glue. It applied as good as I had heard it would and when I checked back a day later, I was impressed.

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JAL3

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The pod hook was glued into place on the motor tube opposide to the engine hook using white glue.

SBG-pod-hook-3.jpg


SBG-pod-hook-4.jpg
 

JAL3

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The nose cone was lightly sanded and then the eye screw was screwed into place, backed out, the hole filled with white glue and screwed back into place.

SBG-nc-3.jpg
 

JAL3

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The launch lug was glued into place along the pod hook with white glue. It was seated on top of the engine hook band.

SBG-lug-1.jpg


SBG-lug-2.jpg
 

JAL3

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A length of sewing elastic provided with the kit was tied to the eye hook and the Kevlar.

SBG-shock-cord-1.jpg
 

JAL3

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The streamer was then secured into place halfway along the elastic with the provided adhesive strip.

SBG-streamer-1.jpg
 

JAL3

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With that the pop pod was done and the rocket was ready to be finished.

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JAL3

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Before I could get started on the finishing, though, curiosity got the better of me and I had to try and hand toss the glider. I took it outside, turned into the wind, gave it a toss...and was flabergasted.

IT FLEW!!!!!!!!!!
IT DID NOT CRASH !!!!!!!!!!!

I grabbed Toby, gave him the camera and made him try and shoot a video.

I launched it again and it flew again, this time making a sharp left turn soon after launch. The video is here: https://www.flickr.com/photos/23694991@N03/3847464424/

Since the glide was not really captured, we tried again, this time with me tossing towards the camera. It seemed to go well until a rocket beating tree got in on the act. Who would have expected the thing to go UP? The second flight can be seen here: https://www.flickr.com/photos/23694991@N03/3847466342/

There was no damage and I had to try again. This time it still flew, or glided, but made a hard right turn. I put it down to the vagaries of the wind eddies around the corner of the house. The third video can be seen here: https://www.flickr.com/photos/23694991@N03/3847467680/

I also realize that finishing will likely change the glide characteristics but at this point I don't really care: a glider I had built had actually glided. That had never happened before.
 

JAL3

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The instructions warn that finishing of this rocket should be done with a light touch in order to minimize weight. All well and good but competitive performance to me took a back seat to just working and looking acceptable. On most projects these days I use Elmer's filler but for this one I went with Balsa fillercoat on the theory that I would be using less of it.

I painted it onto the pod hitting the nosecone and the balsa hook.

SBG-fillercoat-1.jpg


SBG-fillercoat-2.jpg
 

JAL3

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The glider was completely covered with the stuff. I put it on thick figuring I would only apply a single coat, even though that would not completely fill the grain.

SBG-fillercoat-3.jpg


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JAL3

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The fillercoat had a day to dry and then I went after it with #400 sandpaper. The grain on the balsa parts of the pod seemed to have been mostly filled.

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JAL3

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The pod was then brushed off and set up in the booth where it was given a heavy coat of Kilz.

SBG-primer-1.jpg
 

JAL3

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The glider was likewise treated to a scrubbing with the #400 paper. While the grain seemed to have been filled better than I had expected, there was still some that escaped unfilled.

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JAL3

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The glider was then primed with Kilz as well.

SBG-primer-2.jpg


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kjohnson

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The glider was then primed with Kilz as well.

Oh noes! I fear the glider will turn into a brick! How much weight did the filler and kilz add? I know you aren't going for competition like performance, but extra weight is your enemy with gliders.

kj
 
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