
(Contributed - by Bill Eichelberger
- 04/10/08)
Brief:
The Viking is the initial monthly offering (hopefully to be followed by more) by Balsa Machining Services. Originally
produced by Flight Systems, Incorporated, the Viking is a unique looking tube finned, bird with what
should be the potential for "outasight" flights (to borrow an old Estes phrase).
Construction:
The parts list:
- 2 T50H body tubes 9" length
- 3 bias cut T50H
- T50H stabilizer spacer
- T50 equivalent tube coupler
- BNC50X balsa nose cone
- 1/4" eye bolt
- EB24-P engine block
- 36" length Kevlar®
- 18" length of 1/8" sewing elastic
Bill used a copy of the original instructions with this kit. They weren't overly descriptive, but anyone with a
few birds under their belt will have no trouble with the construction. The two halves of the main body tube are
attached with the coupler and wood glue. I then tied the length of Kevlar®
around the engine block and secured it with wood glue, then glued the engine block into the lower section of the main
body tube. The giant was epoxied into the nose cone and attached with a large snap swivel. At this point the
rocket was complete except for attaching the tube fins, which was done with epoxy after all painting was finished for
reasons of masking impossibility. The method for attaching the tube fins is fairly simple. An extra piece of body tube
the same diameter as the tube fins is provided and the first fin is carefully epoxied into place so that the foremost
tip of the fin is flat against the main body tube. Once this tube dries the extra piece of tubing is secured in place
with masking tape and the next tube fin is attached so that all three pieces of tube are flush with each other. The
second tube fin is then epoxied into place and the process is then repeated for the final tube fin.


Finishing:
The normal process of thinned Elmer's Fill 'n' Finish and sanding was used to kill off the grain in the balsa nose
cone, the spirals in the tubes and the seam in between the two body tube halves. As usual, I went with the package art
when painting, which is in this case green. I'm not normally a fan of green and more than likely would have opted for
white with red or blue accents, but the decals came in green so I went with the flow. I couldn't figure a way to paint
the tube fins after they'd been attached to the main body tube, so I painted all of the components before final
assembly. For the nose cone and tube fins I used a Valspar green that matched up well with the green on the decal and
Valspar gloss white for the main body tube. Decals were coated with Testor's Decal Bonder before they were applied and
they were great to work with. The final product looks like something that I'll want to coat with a clear to protect it.
It really turned out great.
Construction Rating:
5
out of 5
Flight and Recovery:
First and only flight to date was at my first QUARK launch of 2008 (and first in almost six months). I'd bought some
C11-7 and D12-7 motors for the launch anticipating several flights, but I'd underestimated the winds for the day. The
Viking on a C11-7 was the third flight of the day and everything about the flight impressed. It left the pad and never
seemed to waver on its arrow straight ascent. It was at ejection that the fun started. I had a small 10" chute on
it and at first it looked like it might be an easy recovery walk, but then it started hanging. I watched as it crossed
the park heading for the Kite Fest. From the , touchdown looked like it was right in the middle of the kite
flyers. I took off after it, careful to keep in line with the landmark that I'd picked out during the descent. As I
neared the soccer field where many of the big kites were flying, I noticed a small, clear parachute blowing around on
the ground. It seemed closer than I was expecting, but there was a lady there waving at me and standing guard over the
Viking. She had as many questions about rocketry as I had about the kites. (Her husband was flying a $1200 USED kite
just behind us, and it was true that some of the big ones could indeed cost up to $18,000.) Impressive flight, but I
knew I'd never have the guts to try it on a D12-7 that day.


Flight Rating:
5
out of 5
Summary:
PROs: Clone of the Month? How cool is that? An FSI clone! How cool is that? The Viking is a great looking bird, and
at $6, you could buy a bunch of them. (And I should have. I need another one to build with an E mount.) Performance is
impressive on a C11 and should really scream on a D12.
CONs: There wasn't a KOTM for March, but I'm still holding out hope for April.
Overall Rating:
5
out of 5

(Contributed - by Chan Stevens
- 08/23/08)
Brief:
This was the first of BMS's recent Clone of the Month program offerings and is a reproduction, slightly upscaled, of
the 1971 Viking I produced by Flight Systems Inc. There were 4 versions of the Viking that year with minor differences
in length and tube/fin styling. This version uses purely tube fins for stability with none of the fin tabs or braces
used in other versions. Featuring a 24mm heavy-wall motor/body tube, think carefully about your motor selection, as
this could almost wind up being a moon shot.
Construction:
BMS's bag o' parts included top quality components:
- 2 heavy-wall BT-50 tubes (9" apiece)
- 3 laser cut heavy wall tube fins (nicely scalloped)
- TC-50 coupler
- Balsa nose cone**
- CR2050 motor block
- laser cut shock cord mount
- 18" length of elastic shock cord
- waterslide decals
- launch lug
- heavy 1/4" eye bolt
- no parachute/streamer--clone kits omit them to keep costs down
** - The original FSI kit featured a hardwood nose, greatly aiding stability. Using balsa for the clone,
BMS chose to include a hefty eyebolt for nose weight. Do NOT substitute a more normal-looking screw eye.
Normally the clone kits do not include instructions. Instead the modeler is directed to one of the online archive
sites such as rocketshoppe.com or JimZ's site. This particular kit though included a reproduction of the original FSI
instructions, which I found kind of neat, having never built an FSI kit before. The instructions were pretty basic
handwritten notes and illustrations, but for an experienced builder, there's nothing terribly tricky about the build
and so instructions are not that critical.
Starting with the finished product in mind, I knew trying to paint the tube fins contrasting color once mounted
would be a pain, so I pre-treated the body tubes and tube fins (including inside spirals on the tube fins) with filler
first. I then drew fin mounting/alignment lines, and masked them off with tiny strips of tape (less than 1/16"
wide).
I glued the two body tube halves together with the coupler, again filling the seam, and mounted the launch lug.
Sliding the nose in place, the various parts were ready for paint [covered in finish section].
Attachment of tube fins was fairly easy. I peeled off the masking tape, applied a small bead of CA to the
alignment line, and mounted the first tube fin, making sure it was as well aligned as possible. For the remaining two
tube fins, I used the supplied spacer (another section of BT50H) and tacked on the second tube such that it fit snugly
against the spacer. If you've ever built a 6-tube rocket such as Totally Tubular, Razor, etc. you'll know once the
first tube's in place, the others are a snap. In this case, as long as you think of every other tube as temporary
spacer, not bonded, you'll be fine.
Figuring the bead of CA would not be enough, I followed up with a tiny fillet of white glue (dries nice and
clear) applied via a syringe (check out Lee Valley Tools online for this sweet little tool).
The shock cord mount is a neat little upgrade to the old tri-fold. In this case, BMS supplied a small
section of heavy-wall BT-50, cut down the length so that you've got a slice about a third of a tube around, by
1.5" long. There are 3 laser-cut holes in this piece, and you thread the shock cord through the holes and tie off
one end. The finished piece is then glued inside the body tube like a regular tri-fold. This has the look and feel of
something much more rugged than the paper mounts, so we'll see how it holds up.
Overall, this is a very simple build, no worse than skill level 2, and I probably had 30 minutes of construction
time in it, plus another hour of prep and paint.
Finishing:
Finishing the main rocket body is straightforward--a couple coats of primer followed by gloss white. I painted the
nose a solid green. Trying to match the green of the decals, I went with Krylon's OSHA green which looks like a decent
match although it's certainly not perfect.
For the tube fins, I wanted to stick with the two-tone look from the FSI catalog, so I painted the insides and
outsides the same gloss white as the rocket body. I then masked off the insides, and painted the outsides the OSHA
green I used on the cone. It really wasn't as difficult as I'd thought, and looks pretty good at the end. For what it's
worth, I caught a suggestion on a rocketry forum by Fishhead (Bill Eichelberger
around these parts) to use silver paint
for the insides. That sounds cool and might be worth a try if I get my hands on another one of these.
After paint, I applied the waterslide decals (which were very good quality and easy to apply) and topped
everything with a couple coats of clearcoat.
Construction Rating:
4
out of 5
Flight:
For the flight, I was a bit paranoid as RockSim didn't like he stability calculations even factoring in the tube fins
with a projected stability margin of 0.15. It predicted fairly straight up flight and put the D12-5 at almost 1500
feet. I asked around on various rocketry forums, and the feedback I got was that it flies fine on D12-5s.
With a nearly perfect day, clear skies and winds under 5 mph, I decided to go for broke with the D12-5. It
weathercocked a bit into the wind but generally flew straight and true. It tested my eyesight a bit, and while not
quite to 1500, I'd bet it topped 1200-1300 with ease. The -5 delay popped the chute just as it was turning over for a
perfect flight.
Recovery:
To keep costs down, no recovery device was supplied with this kit. As BMS Bill quips,the last thing any of his
customers need after all these years is another 12" plastic parachute kit. He certainly had me pegged, as I
grabbed one of the many 12" nylon chutes I have in my range box and slipped it onto the hefty eye bolt. The chute
was a good size as it kept the drift a reasonable walk and provided just soft enough a landing to avoid any damage to
the tube fins.
Flight Rating:
4
out of 5
Summary:
The clone of the month program--in particular this first offering--is an outstanding value. Dirt cheap pricing,
quality components, and the corners that have been cut are things most of us don't need anyway. Having never before
built an FSI kit, this opened up a new set of models and more potential clones that I really like.
The only con I could come up with was that the "Viking I" decal was split in order to fit on a smaller
sheet footprint.
Overall Rating:
4
½ out of 5