View Full Version : American Alliance Emulator
The NB5 Emulator from American Alliance is part of their ongoing "story" of a Pan-American Alliance fighting back after being devastated by aliens. The "NB" of the name stands for "New Beginnings" and it is supposed to be a probe to seed other planets.
Rockets from American Alliance tend to have a "different" look about them. I have several but the only one built before this was the F2 Avenger and I have been very happy with its performance. This one caught my attention because of the triple rear ejecting parachutes.
The photos and videos of the trials and tribulations of this rocket throughout its lifecyle will be found here: http://flickr.com/photos/23694991@N03/sets/72157612363392393/
Whoops!
I gave the wrong link above. It was just for the construction.
The collection for the Emulator is here: http://flickr.com/photos/23694991@N03/collections/72157612409809750/
(although construction is the only thing there so far)
The first step called for in the instructions is the marking of the various tubes. There are 3 BT5s and a BT50. The instructions were unclear at the stage. I believe the phrase "opposite end" was used in place of "other side". This led to some confusion until I had read through the entire set a few times.
I also noticed that the BT50 had a nasty and deep spiral. It serves as the motor tube but will be visible so I decided to go ahead and fill the spirals first off. Using a brush, I applied Elmer's filler and worked it into the groove with a razor blade. The blade was also used to scrape off the excess. Since this left very little material behind, it did not take long for it to dry and the whole tube was sanded down with #400 sandpaper. The spiral, once so prominent, was now hardly visible.
The instructions include a paper template which has outlines for all of the balsa parts. When cut out, it fits exactly over the balsa stock that was supplied. I taped the templates in place and used a razor knife to cut out the three large fins and the three small ones. The similar fins were stacked and sanded to uniformity and then all but the root edges had bevels sanded into them.
The template also included provision to make a jig from the balsa to insert the thrust ring. I knew from pervious experience doing this that I preferred to just use a spent motor casing and this was done. The thrust ring was shoved into place using a casing and was secured with yellow glue.
The small fins were applied evenly spaced and flush against the bottom of the BT50. A double glue joint was used and, when dry, the fins were filleted using yellow glue. I also used the glue as a "sealer" on the balsa since it would only be slightly visible at the end.
A few hous later, the fillets were dry and I did some rudimentary sanding. The motor tube was then set up in the booth and primed with Kilz.
That was given a chance to dry and then the tube was sprayed with a bright red.
When the red paint was dry, I sanded down the outer root edge of the little fins to insure adhesion with the glue. The motor tube and the 2 BT5 chute tubes were then test fitted into the centering rings. The BT5s fit fine but the center holes needed to be sanded a bit to accomodate the BT50. When they fit, I took them all apart again and measured 4" and 1-5/8" from the front of the motor tube since the previous marks had been covered by the paint. A razor knife was then used to scrape away the paint where the rings were to go. The pieces were put back together again and alinged to the marks. Care has to be taken to see that the small fins also align with the three BT5 tubes. Rubber bands come in handy at this point. I glued the rings in place with white glue and applied the first layer of a double glue joint to the bottoms of the BT5s and small fins. When the first layer had dried, I glued the fins to the BT5s and used some masking tape to hold everything in place as the glue dried.
As the tubes dried, I applied Elmer's filler to the large fins. I brushed it on and screeded it flat with a razor blade. About an hour later, I was able to sand them with #400 sandpaper. The result was the nicest set of fins I have prepared to date.
After the glue on the tubes was dry, I tried test fitting the assembly in the upper tube. It would not fit. A fair amount of sanding took care of this. It was still tight and the biggest problem was fitting around the BT5 tubes but it did go into place. When I was assured of a fit, the lower tube assembly was removed and yellow glue was smeared around the inside of the BT80. The first of the centering rings was inserted and then some more glue was smeared just inside the big tube. The assembly was then pushed home until the rear centering ring was flush with the end of the BT80. A long swab was used to apply a fillet around the top of the upper ring.
I tried to test fit the nose cone into the BT80 upper tube. There was no way it was going to fit. I got out the sandpaper and started taking down the shoulder. I got lots of shaving but it was still way too tight. The next apprach was to use the belt sander. that managed to take off quite a bit of material but I eventrually got to the point where I was worried about sanding through the base of the cone and stopped but the fit was still too tight. I took a file and stried to smooth up what had been sanded down; that helped but not enough. My next attack was with #100 sandpaper around the inside of the tube. It was a thick tube, not at all like an Estes tube, and that did seem to help. A little further tweaking on the shoulder of the NC and I was able to finally shove it in. I thought about not gluing it but decided to do so because the base of the cone would bear the brunt of the ejection charge. The NC was pulled out and a ring of tube type plastic cement was put around the inside of the tube and the cone replaced. I don't think that sucker is going anywhere.
The launch lugs were tackled next. The kit has a pair of 1/4" lugs to be mounted on the upper tube. They are to be spaced midway between a pair of the BT5s and one goes flush against the bottom while the other is placed 3/4" down from the top. I used an angle to draw a line and then applied the lugs with yellow glue, using an aluminum rod to keep them aligned.
While waiting for the lugs to dry, I read ahead in the instructions and found that I needed to cut out three shock line covers. These are trapezoidal shaped pieces of basla used to help secure the shock cord mount. A template for the covers was cut out of the same sheet which had included the fin templates and it was taped onto the balsa stock. An X-acto and straightedge was then used to cut them out.
Mark II
01-12-2009, 03:38 PM
This is a really interesting build thread, John. I didn't realize that the American Alliance rockets had such complex designs and that the series had a whole back-story. That shot of the Emulator descending on three chutes that is in your first post is totally cool!
Mark \\.
This is a really interesting build thread, John. I didn't realize that the American Alliance rockets had such complex designs and that the series had a whole back-story. That shot of the Emulator descending on three chutes that is in your first post is totally cool!
Mark \\.
Thanks.
I tend to like the AA rockets. There are a few nFNC's but most are different in some way. The first I built was the F2 Avenger and it is a solid performer, even when I have abused it in terms of motor choices.
I'm looking forward to trying this one because it is different.
The parachutes themselves seemed small but there are three of them. Each consistes of a square piece of mylar, 7" on a side. They were assembled by putting a reinforcing ring in each corner and punching holes through the centers. The instructions say to cut 12 pieces of shroud line, each 10" long. Measure carefully; there is no excees. Each of the lines is then tied to the corner of a chute and hte other end is tied to a provided snap swivel. If I had been thinking, I would have doubled the shroud lengths and used a loop in the end to make the connection; but I wasn't thinking.
The fins were attached using yellow glue and a double glue joint. Each was checked for alignment with the smaller, inner fin and allowed to stiffen up significantly before the next fin was attempted. They also got several layers of fillets.
Mark II
01-14-2009, 11:28 PM
The parachutes themselves seemed small but there are three of them. Each consistes of a square piece of mylar, 7" on a side. They were assembled by putting a reinforcing ring in each corner and punching holes through the centers. The instructions say to cut 12 pieces of shroud line, each 10" long. Measure carefully; there is no excees. Each of the lines is then tied to the corner of a chute and hte other end is tied to a provided snap swivel. If I had been thinking, I would have doubled the shroud lengths and used a loop in the end to make the connection; but I wasn't thinking.
Simple square chutes? That's interesting. I wonder how well they will fill when they are deployed? Is it pretty thin Mylar?
Mark \\.
Simple square chutes? That's interesting. I wonder how well they will fill when they are deployed? Is it pretty thin Mylar?
Mark \\.
The mylar didn't seem too terribly thin. In fact, it seems a bit stiffer than the mylar Apogees sells for streamers.
The photo in the first post shows the church opening pretty well and I think it will probably be fine. Seeing as how they have to be stuffed into BT5s, I think this is probably a decent way to handle the situation. I'll post flight pics when I get that far.
Mark II
01-14-2009, 11:46 PM
The mylar didn't seem too terribly thin. In fact, it seems a bit stiffer than the mylar Apogees sells for streamers.
The photo in the first post shows the church opening pretty well and I think it will probably be fine. Seeing as how they have to be stuffed into BT5s, I think this is probably a decent way to handle the situation. I'll post flight pics when I get that far.
I wasn't surprised by the size, just the shape. But then, I have never worked with parachutes that small, so maybe at that size, a square sheet is standard. Of course it is too soon to tell, and one should give AA the benefit of the doubt (especially given my own lack of experience with this technique).
This rocket just keeps looking cooler and cooler as you progress with the build, John! Nice job!
Mark \\.
I wasn't surprised by the size, just the shape. But then, I have never worked with parachutes that small, so maybe at that size, a square sheet is standard. Of course it is too soon to tell, and one should give AA the benefit of the doubt (especially given my own lack of experience with this technique).
This rocket just keeps looking cooler and cooler as you progress with the build, John! Nice job!
Mark \\.
Thanks for the encouragement on the build. I'm doing so much building at church lately that I don't feel too much like building when I get home, assuming I can still move.
The other AA kits I have included hexagonal chutes. This one is different. I think part of the reason is the packing. THere are very specific instructions on how to fold and insert to insure 3 ejections. Actually there are 2 variations given. I can see how hex chute would be more difficult.
Mark II
01-15-2009, 12:15 AM
Thanks for the encouragement on the build. I'm doing so much building at church lately that I don't feel too much like building when I get home, assuming I can still move.
The other AA kits I have included hexagonal chutes. This one is different. I think part of the reason is the packing. THere are very specific instructions on how to fold and insert to insure 3 ejections. Actually there are 2 variations given. I can see how hex chute would be more difficult.
I guess that now that I think about it, a smaller chute probably calls for a simpler shape, too. And the extra shroud lines might get in the way otherwise.
I like how the design is coming together as you build it. It looks like it is shaping up to be one handsome rocket.
I might just have to get me one of those. :D
Mark \\.
I guess that now that I think about it, a smaller chute probably calls for a simpler shape, too. And the extra shroud lines might get in the way otherwise.
I like how the design is coming together as you build it. It looks like it is shaping up to be one handsome rocket.
I might just have to get me one of those. :D
Mark \\.
I think you're right that the management of the shrouds is a MAJOR consideration. As to the shape, it seems easier to fold as per instruction to catch the full blast. Supposedly, wadding is not needed but helps capture more of the ejection gasses.
I have high hope for the finish. I'm going to try and follow the face card and use white on the fins and BT5s. Blue for the BT80 and NC. I have never had much luck with metallic colored paints but have a dark metallic blue I'm going to try.
No time for anything except a quick layer of fin fillets today.
If there is one part of this build I am most "iffy" about, its the shock cord mounting. The instructions directed me to make a hole in the BT5 tubes just above the tops of the fins. I used a drill to do this.
The three lengths of elastic shock cord were then fed down the three holes so that the ends protruded from the aft ends of the tubes. Only a half inch was left sticking through the holes. The instructions then called for the cords to be glued down on the tops of the fins and warned that I might need to hold them for a while as the glue set. I took care of this by using a gel CA.
The shock cord covers but previous from the balsa were then supposed to be mounted over the cord/fin joint. It was readily apparent that I had drilled my hole just a bit to high on the BT5s and I tried to remedy this by cutting a notch out of the back of the covers. That improved things a bit but its not as perfect as I would have liked. I used CA to secure the shock cord covers and, when dry, I began to try and fair things out with glue fillets.
I am very glad I decided to paint the central tube red before construction. After making it, though, I kinda wish I had gone ahead and painted all the pieces.
The top of the central tube was wrapped with Frog Tape and the tape was used to wrap the bottom of the tube, just above the inner fins. Tape was then used between the fins to mask off the body. I decided to go ahead and redo the inner fins in white since that is what is shown on the face card and because it was easier to mask.
I then used aluminum foil to cover the gaps between the tape and held that down with tape as well. I went over all the tape joints, trying to burnish the edges down with a rounded piece of balsa and then took it to the booth to begin the priming with Kilz.
3 Coats of Kilz were applied. I probably only amounted to 2 regular coats. I realized partway through the first coat that my almost empty can was shooting nothing but aerosols, no pigment, and threw it away. I then let it dry for a while before shooting it again.
FooBag
01-20-2009, 03:50 PM
You definitely have more patience than myself. I would have given up on masking the central tube very quickly and just painted everything the same color. :D
You definitely have more patience than myself. I would have given up on masking the central tube very quickly and just painted everything the same color. :D
It wasn't so much a matter of patience as it was the realization that if I went home, my wife would find something for me to do.
When the Kilz was dry, I gave the rocket a light sanding but left it masked. Next up was the gloss white paint. Again, it took 2 coats and is disticuishable from the Kilz only by the glossiness.
The final masking amounted to wrapping the lower section of the rocket with aluminum foil. Then the final painting, a brilliant blue, began on the upper section.
The rocket received 2 coats of blue and I thought it looked pretty good with the masking in place. I made myself wait until the next day to remove the masking. From a distance, it still looked pretty decent.
Closer inspection revealed some problems. There were places where the white had been able to penetrate the masking a mar the underlying red. This needed to be fixed.
I didnt want to remask everying so that I could spray it so I used one of my kludge procedures. I took the red spray paint I had used and sprayed some into a paper bowl until I had a puddle. A brush was then used to cover up the worst of the blunders.
The Emulator had a day to dry and then it was time to finish up with the decals. The kit came with 2 waterslides printed on a single sheet. They really could have been a single decal but a look at the placement on the face card revealed that the "American Alliance" needed to be cut out and placed separatedly. The decals were on white backed paper and I would have preferred clear with a white backing under the printing but I suspect that is much more expensive to produce. In any event, it doesn't look too shabby.
The Estes Ds are the recommended motors for this rocket. I decided to use a D12-5 for the maiden flight. Accordingly, I prepped the motor and loaded it into the business end of the rocket.
The instruction give 2 different methods for loading the chutes. I chose the "triangular" method where wadding is optional. It basically involved folding the chute into a triangle and rolling it up tightly before stuffing it into the deployment tube. The only hard part was stuffing the elastic into the tube ahead of time.
When it came time to launch, the rocket went straight up, even in spite of the high winds. It was a textbook flight and the 5 second delay seemed about right too. It gave the rocket a chance to nose over before deploying the chutes.
All 3 chutes deployed but the high winds promoted a bit of tangling. Even so, the rocket recovered safely and would have been ready to fly again with minimal prepping. Even so, it did not get to fly again this day because of weather concerns and the time it would have taken to straighten out the chutes.
A video of the maiden flight can be seen here: http://flickr.com/photos/23694991@N03/3280875310/
Photos and videos of the construction, repair and flight of this rocket can be found here: http://flickr.com/photos/23694991@N03/collections/72157612409809750/
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