(Contributed - by Gary Schneider - 03/13/04)
This is a re-release of the early 80's Estes kit. A 1/9th scale model of the
famous U.S. Army surface-to-surface, ballistic missile. This highly
detailed model comes with pre-shaped, accurately scaled fins and molded plastic
nose cone. Spectacular recovery with giant, dual 24" parachutes. It makes
an impressive display model.
This is the Maxi Brute version from Estes. The kit I purchased was undamaged
and all parts were accounted for. This kit comes in a large box which included,
one 2.6" diameter 14" long body tube, launch lug, plastic nose cone,
plastic boat tail and nose cone attachment that you have to cut through the
middle to separate, blown plastic fins that you cut out, as well as blown
plastic spin nozzles that you also cut out. Additional items include two
cardboard centering rings, standard Estes engine hook and 24mm motor mount
tube, two 24" pre-assembled plastic parachutes, various templates to be
used for cutting out balsa parts, one 3x3" piece of 1/8" balsa and
one 1"x4" piece of 1/32 hard balsa-type wood.
The instructions that came with this kit were of the usual Estes quality.
Very clear with good illustrations. One thing you need to do is to be sure to
read the extra set of paperwork that comes with the kit. There is one set of
papers that explains how the kit uses the original set of assembly
instructions, then goes on to list the changes in the re-release and what
parts/construction steps have been omitted. I of course did not discover this
until the instructions said to use the glue capsule that is included with the
kit to glue the spin jets onto the nosecone. This is one of the omitted parts.
Now I guess you just use liquid plastic cement, which worked just fine, since
they did not indicate what to use now that the glue capsule is no longer
The actual building of the kit was pretty challenging. This kit is a level
3 but I would rate it a level 4. I have built several level 3 kits and this one
was the most challenging because of the detail work. For the most part, it
starts out with the basics: construct the standard motor mount, insert into the
body tube, glue the usual way, etc. The challenging part comes in when you have
to start by cutting out the fin halves and making a flange to glue them
together. I made my first modification here. As I was trying to glue the fin
halves together, I thought that these fins are going to break the first time it
lands--or at least pop off. I did not want this to happen and decided to beef
up the fin unit quite a bit.
I took two sheets of 3/16" balsa, made eight 6"x6" squares,
glued two pieces together with the grain running in the opposite direction (so
I now had four 6"x6", 3/8" thick pieces) and cut out new one
piece fins. I could have used four 3/8" thick pieces, but by gluing two
3/16" pieces together with the grain in opposite directions, it is very
strong and does not flex along the grain. I left tabs on the so I
could mount them through the wall for added strength. I then sanded them down
to re-create the high center points. I used an orbital sander to do this which
only took about five min. per fin. After cutting slots in the boat tail for the
fins, I used epoxy to attach them on the inside to the motor mount tube. For
even more added strength, I filled the hollow boat tail with expandable foam.
Needless to say, this thing is as strong as a rock now.
Another modification I made was to use Kevlar
cord attached to the centering ring and Kevlar
cord attached in a loop, per instructions, to the inside of the nose cone.
Between this I added a five foot piece of 1/4" elastic shock cord. I then
attached a 30" chute to the elastic cord about 6" down from the nose.
The instructions say to attach elastic shock cord to the centering ring and
attach a 24" chute to the other end. The nose also gets a 18" piece
of elastic shock cord and it's own 24" chute. I used Kevlar
on the centering ring since the elastic would burn through in two flights. Then
I attached the nose cone and rocket together because I just like it that way by
putting a five foot piece of shock cord between the nose and body so that on
ejection they would not slap together.
The last challenging part was the construction of the launch lug mounts.
Two are decorative and two are actually used to mount the lugs. You have to use
the templates that Estes includes to cut out very small balsa pieces and then
sand and glue together. It is not really that hard to cut them out, it is
gluing them together that is the tough part. They are so small, it is hard to
hold them without getting to much glue around and keeping them from shifting.
First, the instructions say to paint the rocket "Artillery Green". I
looked everywhere for that color and could not find it. I settled on
"Medium Green" from the Testors Master Series line of paints. I
suppose you could use "Olive Drab" but I did not think it looked as
nice as the medium green. I figure if it is a scale kit, and I took the time to
build it as close to scale as possible, then Artillery Green should exist. The
"updated" instructions did not say anything about the paint color
changing names, but I suppose that back in the early 80's when this kit was
introduced, the paint name may have now been changed to "Medium
The other thing I did not like was the peel and stick decals after I had
them on. Again, since this is a scale kit, I would have preferred the water
slide type. Peel and stick may be easier, but they leave a big lip on the edges
of the decal because they are very thick. Water slide decals are very thin and
when dry, are almost flat with no lip edge.
Before painting, I applied three coats of sanding sealer to the fins
sanding between each coat. Painting was simple and straight forward since it is
all one color. I applied two coats of Krylon white sandable primer, then two
coats of Testors medium green. I had no problems applying the decals, and after
they were on I applied two coats of Krylon clear matte finish. Total weight was
15oz after paint. This is only one ounce more than the specified weight of 14oz
on the package. My guess is that the weight on the package was a little high
because I can't believe I only added 1oz of weight between the heavier balsa
fins, epoxy, and foam inside the .
out of 5
For the first flight I flew this on the recommended Estes D12-3. Weather was
optimal and the rocket looked great just sitting on the pad. Upon ignition it
roared to life and lift-off was great. Not too slow and not too fast. It went
straight and reached an altitude of about 250ft.
The next flight was on an Aerotech E18-4. Again, weather was optimal. No
wind and very clear. The E18 made it roar off the pad much faster than the D12
and it went much higher. I would guess about 400 to 500 feet this time.
Recovery was successful on the D12. The 30" chute popped just after apogee
and since there was little to no wind, the rocket came down about 100ft from
the pad. Recovery on the E18 seemed perfect. This motor had a longer delay by
one second, but since it was a more powerful motor it coasted a bit longer than
the D12 and the chute popped at just the right time. This time it landed a
little farther from the pad.
After the two flights, there is some slight zippering on the edge of the
tube from where the Kevlar
cord would pull against it at an angle. The cords looked in good shape with no
burn through and the elastic shock cord had no visible signs of wear, or black
½ out of 5
Overall I think this a great kit and looks great as a display model. You don't
see many of these around at club launches and that's what I think makes it
pretty unique. I think it is a bit pricey though, as I paid about $43.00 for
the kit. That is a good price but still on the high side.
It is definitely not a kit for beginners, hence the level 3 rating, but if
you take your time on it, it will turn out spectacular.
I like the looks of the finished kit so much that I would like to make a 2,
or 3x upscale version of it to fly on either 29mm or 38mm H and I motors.
½ out of 5
(by Robert Tung -
This is a good kit! You have to make sure you glue the fins on good or it won't
be a stable flight!
The kit contains:
- 1 body tube
- 1 nose cone
- 2 sets of plastic molded fins
- 1 boat tail
- 1 nose cone tail
The instructions were very good and easy to follow. It was hard to make the
fins stick onto the rocket.
I forgot to add glue fillets to the body tube to get rid of the spiral marks.
You need to make sure there are no air bubbles in the decals.
½ out of 5
I used a D12-3, the recommended motor. Put the nose cone parachute in first
then the body parachute. It used 14 pieces of wadding and flies fairly
Recovery was perfect.
out of 5
Everything is exceptional except the fins.
½ out of 5
(Contributed - by John Lee - 07/12/08)
This kit was an eBay find. It was already opened but all pieces were reportedly present. I took a chance and bid on
it, paid too much, and squealed with delight when it arrived.
The Hojo starts, as do most kits, with the motor mount. A spacer is marked at 1/4" and used to push a thrust
ring into the motor tube. On inspection, I noticed that one end of the motor tube was ovaled but the other end was
round. I decided that the oval would not cause any problem if it were oriented forward so I inserted the thrust ring in
the opposite end.
The instructions then had me cut a slit for the engine hook. When I tried to cut at the mark I had made, I
encountered resistance as the blade came into contact with the already mounted thrust ring. I moved the slit down just
a bit and the resistance was gone. I then used a bit of tape to keep the hook from moving about for the next step.
Kits often have thin rings to slide over the engine hook and keep it in place. This kit goes a step farther and
uses what Estes calls a BT-52 tube almost 4" long for the same purpose. A mark is made an inch from the end of the
motor tube. The instructions indicate to apply a generous amount of glue is then applied along the hook from the mark
to the forward end (even with the slit) and the BT-52 is slid over the hook.
Next, the cardboard centering rings are removed from their stack material and sanded to remove the attachment
points. They are also checked to make sure that no sanding is needed to either fit around the motor tube or into the
BT. Mine needed minimal sanding and just a little patience to work over the oval at the forward end.
The motor tube is marked in 2 places and the rings are slid on. The one with the slot in it goes forward. The
rings were glued in place with yellow glue and filleted.
After letting the fillets set up for a couple of days ("She who must be obeyed" had some things for me
to do), I marked the inside of the BT-80 for where the second ring was supposed to be. I gave both of the rings a bit
of sanding to make them fit more smoothly and checked to make sure the fit was easy to position. I then smeared a ring
of glue into the BT and shoved the motor tube in with just the first ring on the inside. I then swabbed another glue
ring at the mark and pushed the assembly home. It went in easily, which can be a warning sign.
The instructions are very explicit about making a good seal around the things to prevent ejection gases from
escaping. With that in mind, I placed generous fillets on the approachable faces of both rings and set the assembly to
the side to dry.
About the time the glue had set up past the point of making any more changes, I noticed a blunder on my part. The
forward centering ring had a slot in it intended to mount the shock cord. I was planning on making a loop of Kevlar
around the motor mount and then cutting a notch in the edge of the ring to pass the Kevlar
At this point I need to digress a bit and mention that in this model, Estes was providing nice 1/4" sewing
elastic instead of the raw rubber band. That made for a pleasant but, now unrealizable, memory. Now back to our
Not quite believing what I was doing, I found myself cutting a long length of the heavier Kevlar
and tying a loop in the middle. I then used an Estes "Safe Rocketry" brochure to construct an oversize
tri-fold. The mount I constructed had both ends of the Kevlar
glued in. The loop for attachment is in the middle. I also made a fairly wide mount to distribute the stresses over a
greater area. I installed the mount with yellow glue.
The next step is to apply the circumferential bands around the BT. The kit comes with a sheet of heavy cardstock,
some of which is used for templates and some which is used to form these bands. There are 3. Each is placed on top of
the previous making the whole the thickness of triple cardstock. They are applied with yellow glue and the instructions
indicate that the ends should not line up over each other. The first two bands are plain and the third has a
line of circles on it which are supposed to be cut out.
I applied the 2 bands without any problem but was at a loss as to how to punch the needed holes in the third. I
decided to investigate a hole punch at home later on and skipped to the next step.
The nosecone is plastic, as is the fin can, the fins, and another part I will call the nosecone base. The NC base
and fin can are cast as a single unit. The instructions had me saw the 2 pieces apart. I then used a bench sander to
take the plastic down to where it was supposed to be. His involved about 1/16" on both pieces.
The instructions say to use a razor knife to drill 2 holes in the NC base. That seemed entirely too much effort
when I noticed that I had forgotten to put my power drill away a few days ago and that drilled the holes nicely. I then
passed one of the pieces of sewing elastic provided through the holes and then tied the ends together, forming a single
large loop. This is supposed to be the shock mount for the NC. The NC base was then glued into the NC after sanding the
edges down a little.
Next up were the fins. This is my first attempt to work with vacuformed plastic. While I see the advantages, at
this point I am not a fan.
There are 4 fins and each fin comes in 2 halves. A razor is used to score a line between the parts and then the
plastic is folded to snap apart. This actually worked well for me. I had thought that the plastic would be thinner.
The fins then needed to be cut down to size. You are supposed to score and snap leaving about 1/8" of excess
material. This probably would have been fairly easy if each edge of the fins were straight. One edge is not straight.
That made my life more difficult. I finally settled on using by bench sander to remover material to within the given
margins. I cleaned up the edges with a razor and some hand sanding also.
In instructions indicated that I should use a piece of 100-150 grit sandpaper to thin the edges to about half
their original thickness. This was done with unknown effects on the efficacy of putting the things together.
Liquid plastic cement was used to join the 2 halves. There are no guiding lips or alignment holes. Everything is
done by eyeball and hoping for the best. These parts are then set aside to dry.
When I got around to working on the third circumferential band, I thought I would use a hole punch to make nice
and even little hole. When I checked, though, the holes would have been too large. As I was returning the hole punch to
the drawer, I noticed a leather punch with multiple spikes for assorted hole sizes. On checking it out further. I found
that the largest of the spikes was just the right size. After that, punching the holes was not a problem although I did
have to stop and clear out the "chads" every now and then. Once the holes were punched, I cut the band out
and glued it over the previous two.
I have to admit right here that working on the fins has been the most tedious part of this build. After getting
the two vacuformed halves together to make 4 fins, there was still a lot of sanding, filling, sanding, trimming,
sanding, cursing, sanding, re-gluing, and sanding to be done. The material from which the fins were formed has to be
removed right up to the edge of the profile. On the straight sides this is not too bad but along the root edge it
becomes much more complex. There is a piece that hangs over the top of the fin into a depression. The fin needs to sit
flush and straight. Sometimes the removal of material opens up a cavity that needs to be filled. It seemed to go on
The process was basically this: I trimmed off as much as I could with a razor knife, used a sanding belt to
remove material to as close to the fin as I dared, hand sanded to remove burrs, sharp edges, etc., filled cavities with
green Squadron putty, sanded some more and test fit some more. I finally reached the point where my
"enjoyment" was decreasing to a level incommensurate with a "hobby" and figured it was good enough.
The fins are supposed to be mounted on the fin can with plastic cement. In the past, my luck with this stuff on
fins has not been too good. This is true of both the tube type and the liquid solvent. I decided to fit these fins with
5 minute epoxy. I mixed the epoxy in small batches, each just big enough for one fin. I then applied it to the root
edge and pressed the fin to the fin can. The front of the fin fits into a little indent which helps but is not enough
to really make sure they will all line up together. Most of the fin is centered on a mold line on the fin can. The
epoxy method seemed to work well. After each fin was done, I went on to the next one, eyeballing things along the way
to make sure they were straight.
Mounting the fin can to the body tube posed no problems at all. The instructions indicated that the joint was to
be made with tube type plastic cement but I elected to use 5-minute epoxy again. The fit was rather loose so no sanding
was needed. I mixed a small amount of epoxy, spread it in a ring around the inside of the BT, and slipped it on. I
checked the aft end to make sure the motor tube was centered and it was as simple as that.
After dealing with the fins, I was not too enthusiastic about working with the spin motors which came on the same
vacuformed material as the fins but they did not turn out to be too difficult. On the first motor, the excess material
was trimmed away by scoring and snapping of the plastic. I then sanded down to the change in contour. For the other
three, I followed a similar procedure but with an important difference. I tried to score a line right where the
material transitioned from flat to profile and then use the excess material as a handle to snap it off. That worked
well and I was left with only minor sanding.
The result of the previous step was a series of 4 spin motors which looked fairly nice but which had flat bottoms
needing attachment to a round nosecone. To rectify this, I used the procedure spelled out in the instructions to good
effect. I wrapped a piece of #100 sandpaper around the NC where the spin motors were to me mounted and then rubbed the
motors back and forth to achieve the desired profile.
Each of the spin motors was attached to the NC along a line molded into the plastic of the NC and 1" up from
the bottom. I used the liquid plastic cement for this and it seemed to make a good join.
The kit comes with a strip of thin balsa and a small sheet of thicker balsa. This is used along with the provided
templates to cut a bunch of small parts that are used for detailing and offsetting the launch lugs. I expected this to
be rather tedious but it did not turn out to be so.
For the thick balsa, there was just a single template for the two different types of parts. Two copies were
needed of one part and four of the other. I cut the template out with scissors and transferred the lines to the balsa,
noting the orientation of the grain was compliant with the directions. Once the parts were marked, I used a razor and
straightedge to cut them out.
The thin sheet had enough template for each of the parts to be cut. I taped the
template to the balsa strip at a place where the tape was smaller than the part being cut and then proceeded to slice
the parts off.
After the pieces were cut out, it was fairly simple to glue them together. A pair of skinny bands was glued to
either side of the fin-looking things. When the glue was dry, the excess overhang was cut off and the edges sanded. A
cover plate was then glued on top. When that glue was dry, it was sanded to conform with the rest of the bevel.
A similar but wider assembly was put together for the lower portion of the rocket in the same manner.
And finally, two more things were made which each resemble half of the previous thing. All of these things are
referred to as launch shoes in the directions.
The launch shoes for the nose cone are mounted on opposite sides, 180 degrees from each other. The kit provides a
bulb of cement with which to do this but I opted to use epoxy.
The lower launch shoes will not fit right on the rocket without sanding the profile of the BT into the
assemblies. Accordingly, the BT was wrapped with #100 and the curve was sanded into the mounting surfaces.
I decided to use epoxy again to mount the lower shoes but there was some confusion in my mind as to exactly where
they were to go. Both assemblies are mounted 180 decrees apart and centered between the fins but my problem was in
locating them fore and aft. They seemed like a natural to be glued directly to the BT but the drawing in the
instructions clearly shows them mounted on the plastic fin can, protruding to the level of the fins. That leaves a bit
hanging off. Even so, that is where I epoxied them.
PROs: straightforward and mildly challenging, nice looking
The finishing of the Hojo started off with a coating of Kilz. This filled mostly the balsa, covered up the writing,
and gave a bland, flat white surface. When the Kilz had dried, I gave the entire rocket a gentle sanding. The entire
rocket was painted with Testor's olive drab. It took 2 cans.
For me, the biggest disappointment with this old kit was the decals. There weren't any. Instead, I got some crack
and peel stickers. This surprised me for a couple of reasons. First off, I expect the upper level Estes kits to have a
higher quality. Crack and Peel makes sense for RTF Walmart kits but not for something like this. Secondly, the
instruction specifically make reference to, presumably, waterslide decals. There is a warning to let each decal set
completely before starting the next so that they do not slide out of place. Crack and Peels do not slide around.
I remember thinking that the "decals" seemed kind of thick but my brain was just barely turning over. I
cut out the first one and set it in a bowl of warm water. After a while, I noticed that it was just sitting flat on top
of the water instead of curling up like the water slides usually do. I pulled it out of the water and looked more
closely at the master sheet from which it had come. Sure enough, it was crack and peel.
Fortunately for me, the first sticker was not damaged. I proceeded to place the stickers as instructed as sat
back to admire my flat painted rocket with all of those high gloss stickers.
CONs: stickers instead of decals
½ out of 5
Flight and Recovery:
The day finally came for me to launch this one and I was jazzed. I selected a D12-3, inserted about a dozen pieces of
wadding, and then prepped the chutes.
I should mention here that the model is intended to come down in 2 sections, each with its own chute. I'd rather
keep it all together. I fashioned a Kevlar
harness and then used sewing elastic to connect the NC to the harness. I also used two 18" nylon chutes. Each was
connected to the harness with about 4' of sewing elastic.
The liftoff was as slow and dramatic as promised. It flew straight and true and blew the NC at apogee. It wasn't
all that high but it was beautiful. It drifted down gently under the tandem chutes.
For the second flight, I decided to go with an AT E15-4. The rocket was set up the same way as before and
everybody pause to watch. At ignition, there was some and I had just come to the conclusion that it wouldn't
go off when it did. It was not as slow as before but it was a great flight straight up.
It hit apogee and started to turn down. After all, it had an extra second to work with. It kept coming down,
faster and faster. Unless my eyes deceived me, it was accelerating at about 32 ft/sec^2. Finally, about 100 feet up, it
ejected and everything deployed normally. Upon inspection of the bag the motor came in, it turned out to have a 7
second delay and not 4. I had it stashed in the wrong bin.
PROs: Beautiful straight flights, awesome liftoffs
½ out of 5
This is a nice rocket marred primarily by the crack and peel stickers instead of decals. I still like it though and
am glad to have it in the fleet.
½ out of 5