(10/02/00) My third 4"
rocket this year became the NCR Big Brute which was built after the
Bullet. The Big Brute is much closer in size to the Diablo being
33.3" in length and 4" in diameter.
my 4" Stubby Rocket Comparison Page
The Big Brute is a nice looking rocket with it's
decals, black nose cone (as pictured in the catalog), four fins, and stubby
design. Then the rocket touted features like laser cut plywood fins,
pre-slotted airframe, interlocking through the wall fin construction and the
Gorilla steel cable shock cord mount and the Gorilla-Lok motor
mount. I was pleased to get a look at this Gorilla-Lok motor retainer
considering I didn't get it when I purchased my
G. I'll talk about my disappointment later.
Brute includes a 17" long paper, pre-slotted airframe. The plastic
nose cone makes up the remaining length. There are four (4) 1/8" thick
plywood fins that are pre-cut. There are also three (3) 1/4" thick plastic
centering rings (slotted to accept the fins). The motor mount tube is NCR's
just-smaller-than-a-29mm and it included the Gorilla-Lok retainer that
slides into the lower centering ring and then turns to lock. The recovery
system includes a steel cable with loop/sleeve connectors, 6' of 1/2" flat
elastic and a 24" red, nylon parachute. There are two (2) 1/4" launch
lugs and a decal sheet to make up the remainder of the kit. All of this is
nicely protected in a box.
There is a 7-page instruction booklet of which 3 pages
are the actual construction steps. The are clear illustrations to assist in
building the rocket. There was also an extra loose piece of paper in my box
explaining that the fins will hang below the body tube by 1/4" and if I do
not want that to cut the fin slots a 1/4" so that the fins align with the
bottom of the body tube. I choose not to do that.
There are two other 1/4" plastic centering rings
that each are slotted for the four fins. I had to wrap a piece of tape in place
in the middle of the motor tube because the centering rings fit loosely. I then
slide the middle centering ring to rest on the tape while gluing. When gluing
on the the bottom centering ring, I used two of the fins by sliding them into
the slots to ensure the two rings were aligned properly. This is really the
most critical part of construction.
Building the Gorilla recovery system including
sliding the steel cable through two holes in the upper centering ring and then
crimping a sleeve into place to hold it. Then making a small 1" loop at
the other end using the second sleeve and then the elastic shock cord is tied
to that. This connection to the centering ring appears to be very strong as the
centering ring is made of 1/4" plastic.
After the motor mount is assembled and glued into the
body tube, everything else goes together very quickly. The fins slide right
into there slots. The slots are not sloppy so the fins actually are held in
place. This is a nice set up and allowed to have perfectly aligned fins (as
long as they were aligned when building the motor mount).
The two launch lugs are glued in place. The elastic
shock-cord is attached to the nose cone and she's ready for finishing.
For finishing, I didn't need to use anything to fill the
spirals as they were very shallow. I simple used several coats of Plasti-Kote
Sandable Primer. I had to spend a little more time on the nose cone seam but
still only used primer for filling. I then painted the entire rocket red
(instructions suggest grey). I followed up by painting the nose cone black.
Then came the decals.
The decal sheet consisted of three (3) strips, the words
Big Brute and eight (8) fin decals. All were black and self-adhesive. I used
the strips that go around the top of the body tube and the Big Brute name. I
did not use the fin decals. I would have if they looked like the ones in the
pictures on the front of the box. The decals supplied with my kit had the same
shape but were much smaller. The picture on the box shows them evenly covering
the fin with about a 1/4" space all the way around. The ones I had seems
to leave at least a 1/2" space and not evenly around. My guess is that
something changed, either the decals or the fin size. They just didn't give the
look I wanted so I didn't use them.
Interestingly, my finished rocket weighed in at just
under 27 ounces. The specs on this rocket says 16 ounces. I'm sure I didn't use
11 ounces of extra epoxy. I again wonder if the fins were enlarged thereby
increasing the weight and making the decals not fit the same way.
Overall, for CONSTRUCTION I would rate
points. Instructions are not the best in town, but are adequate for
building this relatively easy rocket. The centering ring and fin alignment are
excellent. The smaller than normal motor mount must be changed by NCR and
someone should look into the weight and decals.
Here are the
Apogee's RockSim says it will get.
Brute was designed to fly on NCR DarkStar motors but . . . since you
can't get them any more you must fly on alternatives. Since the motor mount is
slightly smaller than the standard 29mm, normal single-use motors do not fit.
However, AeroTech RMS motors do. Therefore, the first flight on my Big
Brute was on an F22-5J(4)*. Note the (4)* indicates that this was the
delay that certified.
I added a Large
Pratt Hobbies Nomex
Shield which fits great in 4" diameter kits.
Gorilla-Lok retainer ring is designed for handling NCR motors. I tried
and tried to get it on over my AT RMS casing but could not. Finally I took a
wood screw and drove it into the plastic and used a washer as a motor retainer.
The plastic actually gives an easy surface to screw into and it is
I had prepped everything, so I thought, so that once I
was at the site I could just pop the rocket on the pad and go. Well, I loaded
an ignitor at the site and popped it on the pad. After a countdown and the push
of a button, the Big Brute lifted off the pad. I had angled the rod
slightly to compensate for wind. The rocket took off in a slow arc and was
heading down when the ejection charge popped. Upon ejection the red parachute
seemed to go one way while the rest of the rocket fell. It continued that way,
falling, until it landed in the tall grass. The parachute landed a good
distance away. Frantically searching to see if the ejection blew the shroud
lines apart or something I was only to discover that I never tied the parachute
No damage to the rocket as it fell horizontally and
landed in tall grass. So the flight was successful, but sure would have been
nice to see the descent on a parachute.
The second flight was a couple of weeks
later and this time I had attached the parachute. I loaded another F22-5J(4)*
and off she went. This time with no angle on the launch rod, she went straight
up, arced over and started back down. It dropped about 1/3 of the way and I had
started to write it off in my mind when it finally popped the ejection. Under
full parachute the rocket still fell too fast.
Size Calculators suggest between a 36" and 38" chute for minimum
on this weight of my Big Brute.
For FLIGHT/RECOVERY, I would rate this kit
½ points. The short rocket looks nice coming off the pad. Due to
it's motor limitations and the fact the provided retainer doesn't work except
with NCR motors and you can't get these motors the rating for this rocket is
only average. This kits parachute is under-rated for the weight of the
Overall, the Big Brute is another
nice looking "stubby" rocket. The parts are good quality and the
through the wall fins set up is great! The instructions are adequate with
illustrations. Too bad the rocket is designed to fly only on the NCR DarkStars.
It forces people to modify, which kind of defeats the purpose of a kit for less
experienced rocketeers. I give the kit an OVERALL rating of
(by Nick Hills)
Length: 33" Diameter: 4" Motor Mount: 29MM
The instructions for the Big Brute
were fairly easy to follow. But one of the diagrams are wrong! The diagram for
putting the launch lugs on, DO NOT use the diagram for this step. Do what
it says in the instructions! The tools needed for the construction of this rocket
are: 5 minute epoxy, CA, sanding sealer, 3/4" masking tape, X-acto knife,
ruler, pliers, sanding block and sandpaper.
All parts fit well. You will want to replace the NCR motor tube with a LOC
29MM motor tube so you can use Aerotech motors in the rocket! Also you will
want to put some blind nuts in with Kaplow clips so you can retain the Aerotech
motors easily. And make sure NOT to get ANY epoxy were the Gorilla motor lock
goes, if you do then you can not use there lock.
The decals they give you are nice, I would recommend putting
water a drop of soap in a bowl to apply them sense they are so big! The
finished rocket looks great!
For the first flight I used a NCR F62-4 Dark Star. Rocket had a good flight
and recovery! This is a great rocket if you don't have allot of room!
I would give this kit
points. If it had a "real" 29MM motor tube I would give it 5
The following excerpt is
from "Sport Rocketry". The intention is to allow guests to get a
basic feeling about a kit. We strongly suggest that you get a copy of the
referenced Sport Rocketry and read the entire article. Inside you will find
many helpful hints in construction as well as other useful information. For
more information, use the two links above.
(Sport Rocketry - Jan/Feb 1998 - page 38 - by Thomas Beach)
"The new incarnation of the NCR Big Brute from Estes features
a plastic nose, plywood fins, steel cable Gorilla shock cord mount, 24"
parachute, and self-adhesive decals."
"The most interesting feature of the new Brute . . . are the centering
rings and through-the-wall fin mounting system."
"The centering rings are molded plastic with slots to engage the fins . .
. adding strength to the fin and motor mount structure."
"Several of the diagrams in the instruction do not exactly match the
appearance of the actual kit assembly (which disturbs a visually-oriented guy
like me) but if you follow the text of the instructions you will do
"The self-adhesive decals work well."
". . . the instructions say the model should weigh 454 grams, and mine
tipped the scales at 673 grams . . ."
"The motor is held in place by a twist-on motor retainer ring (a thrust
ring is molded into their base of every Dark Star motor)."
The entire article
gives the impression is that this model is good choice for
beginner/intermediate mid-power modelers.