Construction Rating: | starstarstarstarstar_border |
Flight Rating: | starstarstarstar_borderstar_border |
Overall Rating: | starstarstarstarstar_border |
Manufacturer: | Semroc |
Brief:
In 1973, Estes released 6 pretty wild (for Estes) designs loosely resembling the Baby Bertha of today but with
relatively zany fin and decal schemes. The were called the "Goonybirds" and after a 2-year run went out of
production. They have since survived only through the cloning efforts of die-hards (Bill Eichelberger comes to mind)
and through kitbash plan/decal packs available through Excelsior Rocketry. In the fall of 2007, a thread on Ye Old
Rocket Shoppe was started attempting to document as thoroughly as possible the history of Estes designers and their
respective creations. During the ensuing dialog, a few sketches of some Goonybird design proposals that didn't make the
cut surfaced. The designs were not exactly politically correct and were rejected for fairly obvious reasons, but the
Mad Magazine-like humor holds a certain appeal to adult rocketeers. So Semroc jumped on the concept and has now
released two of these as "Groonies" becoming grown-up goonies. The pair include the Russian bomber style
"Ruskie" and the Japanese zero "Saki".
For more information on the original sketches, as well as the complete thread, check out the Rocketshoppe forum.
Construction:
At this point, we probably just need a boilerplate header for all Semroc reviews: the parts are exceptional quality,
you get a lot of stuff packed into a bag/box full of value, and the instructions are clearly written with plenty of
illustrations. In fact, I think I'll bookmark this review so I can just cut/paste to simplify future reviews, as I'll
surely buy more of their terrific products.
This specific kit includes
The motor mount is pretty straightforward with a metal clip/hook, a BT-20, a pair of 20/60 rings and a motor block. The Kevlar® anchor slips under the forward end of the clip and through the 20/60 ring. The finished mount then goes inside the BT-60 body tube, recessed enough that the motor clip is completely hidden and flush with aft end of tube.
There are 5 total fins, one of which is a two-piece assembly, so if you want to fill grains, you'll have a lot of work. In my case, a couple of coats of dilluted wood filler and sanding added about 2 hours to what was otherwise a 90 minute build (plus paint). The top fin (rudder) is a two-piece due to its funky shape versus the balsa grain and mixing the grain directions on the assembled unit will add strength.
The 5 fins are bonded to the body tube along lines drawn via a marking guide included on the instructions. I'd prefer a wrap-around guide, but if you've got a steady hand the marking guide works fine too. The 5 fins are odd-shaped. The two on the "bottom" (if this flew horizontally like a plane) are cloud-shaped, while the two "middle" fins are standard wing-like shapes and the upper fin is intended to look more like a rudder. In my case, the balsa was very soft/pliable and the fins sit at such odd angles there's really no way to set this down during construction that doesn't apply some pressure to a fragile joint. I suffered three cracked fins just during the build, all along the grain lines.
Finishing up with the elastic for the shock cord and the parachute assembly. Then you're ready to paint.
Finishing:
As noted earlier, if you want a nice finish there will be a lot of work involved. Mainly balsa grain treatment (5
fins and the nose) but also a bit of work on the tube spirals. I have started using the Fill N FInish small tubs
available at the nearby big-box retailer (rhymes with nose), so spirals don't take too much work.
The paint scheme could be a simple white or for a splash of color paint the nose separately with a cherry red and the wing tips red.
The decals are great to work with. They are srong enough to allow a little sliding into position, but thin enough to look painted on. If using a decent gloss coat before decals, the clear is practically invisible. My only beef with the decals is that the ones designed for the lower cloud fins were a little oversized. I pointed this out on a forum and got a decent tip. Instead of applying them as a single piece, cut them into 2-3 sections overlapping a bit on the clear portion.
Construction Rating: 4 out of 5
Flight:
As draggy as this thing looked, I was a bit suspicious of the 300 foot estimate for the B6-4 and jumped all the way
up to a C6-5 for first flight. I was surprised as it flew up fairly quickly, with a minor spin all the way up. I doubt
that it quite hit the listed 725 feet and would estimate my actual apogee to be around 600. The 5 second delay was a
good fit, occuring just after it arced over.
Recovery:
The 12" plastic chute was fine though as fragile as the fins are. I'd consider at least a 15-18 inch if flying
on hard ground or anywhere near rocket-eating roadways. Mine was recovered without damage as it landed on fresh, soft
snow.
Flight Rating: 3 out of 5
Overall Rating: 4 out of 5
Other:
Make sure during the flight prep that you include plenty of wadding/dog barf. This is a BT-60, not a BT-20 and the
chute will be packed pretty close to the forward end of the motor.
Based on the original Estes Goony Bird, the Zoom Broom. Late last year the original concept sketches for the Goonybirds appeared. Estes used the Goony profiles but changed t he graphics before they were released. Due to the interest generated by the original sketches, Semroc chose to release a new line of Goonies called the Groonies. Carl, the owner and founder of Semroc, refered to these as ...
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M.D.B. (December 9, 2008)