Madcow Rocketry Momba

Madcow Rocketry - Momba {Kit} (K-100)

Contributed by Larry Brand

Construction Rating: starstarstarstarstar
Flight Rating: starstarstarstarstar
Overall Rating: starstarstarstarstar
Diameter: 2.60 inches
Length: 23.75 inches
Manufacturer: Madcow Rocketry
Style: Sport

Photo Courtesy of Mad Cow    
Courtesy of Mad Cow

The Momba by Madcow Rocketry is a new kit for F-G motors. The Momba kit is a conventional 4FNC design deluxe product featuring full through-the-wall fins mounting to motor tube, laser cut fin slots, and what has to be the most complete accessory package in the industry, including a Kevlar® shock cord, Nomex® chute protector, high quality nylon chute, machined solid balsa cone with ballast box, the lead shot ballast to put in it, and steel eye-bolt. There is nothing else to purchase but glue and paint. Construction time is about an hour. The Momba is a close to an "almost ready to fly" rocket as you will find for a mid-power rocket.

My Momba kit arrived packed in foam popcorn and in perfect condition. The laser cutting of the 4 ply fins and body tube was impeccable. As evidence of the superb fit and finish of the parts, I was able to completely test assemble the Momba with no adhesive. The solid balsa cone is unusual for a rocket of this size. The attached ballast box struck me as such a neat idea that I decided to make the ballast in mine completely removable via a trapdoor built into the bulkhead. The instructions are superb, however, I noticed that they didn't include instructions on finishing/painting a balsa cone of this size, which may be new territory for builders more familiar with the plastic variety. I offer some tips of my own for this below.

Madcow Rocketry MombaMadcow Rocketry Momba

No sanding or trimming of the components was needed as the kit test fit together perfectly. I used 5-minute epoxy for all construction. It goes together just like a Big Bertha:

  1. Motor tube and shock cord assemble with centering rings
  2. Motor tube assembly epoxied into body tube
  3. Fins epoxied into body slots, contacting the motor tube--very strong!
  4. Unique ballast box with shot ballast assembled per instructions.
Madcow Rocketry Momba

As I mentioned, I decided to make the ballast shot in my kit removable. This was done simply by drilling a 3/8" hole in the aft bulkhead and covering it with a piece of scrap light plywood held in place with 2 small screws. By removing all the ballast, good performance can be achieved on as small as an E30-4 by adding 4 more ounces of lead (split-shot sinkers) than comes with the kit. Momba can be perfectly ballasted to fly on 29mm H-power such as the popular H128W-M or H165R-M too. It clearly has the structural beef to fly on a heavier motor than the manufacturer recommends, provided additional ballast is added. Sims say a Level 1 Momba flight on an H128W-M would be at the virtually same speed and G's and only about 250-300ft higher than on the recommended G80-7T.

Another tip I would offer when assembling the eye-bolt to the nose cone is to gob some epoxy on the remaining threads so they don't loosen after everything is sealed up.

Madcow Rocketry Momba

I painted my Momba in camo colors after applying a single light undercoat of Testors Flat White spray. I'm not a big fan of the many balsa sealing products available because they tend to chip on impact. Here's how I prepared my Momba's cone for painting thanks to a few old tips from an old R/C flyer:

  1. End grain balsa hates sanding. Instead, I first gently rubbed the cone with my thumbnail to press and seal the grain. Just take your time; this works well.
  2. The cone was then quickly smeared with freshly mixed 5-minute epoxy. Use a rubber glove, finger cot or Band-Aids to protect your skin. Take care not to get any on the base that slides into the body tube.
  3. A balsa cone so prepared can be lightly sanded to a very smooth surface that takes paint well.
Madcow Rocketry Momba

Construction Rating: 5 out of 5

Flight and Recovery:
First flight was on a single use F23-4. This is a perfect load for the Momba, and the flight couldn't have gone better. On the second flight with an F50-9, Momba experienced a separation--the nose cone broke loose at the knotted loop for chute in the Kevlar® shock cord. Ejection was very late due to my using the 9-second delay with this motor instead of the recommended F50-6. Still, I was surprised to see the high-tech Kevlar® fail. No harm done, the balsa nose cone was recovered without a scratch--not only because of my epoxy covering, but also because it falls base first with all that lead shot back there! I'm assuming this was my fault and was not associated with the high tech shock cord. Last flight was on the recommended G80-7, and it went off without a hitch. At a simulated height of 1530' at 335 mph on this motor (it looked to be about that) and a projected height of only 1800' at 355 mph on an H128W-M (more than Madcow recommends) using 4 oz of additional ballast, I think Momba has lots more potential for the adventuresome.

Flight Rating: 5 out of 5

Madcow Rocketry Momba

I was extremely impressed with the Momba kit. It is more complete than anything out there, and Madcow Rocketry has spared no expense to provide a very deluxe kit that lacks nothing--who else gives you a Nomex® pad and lead shot for ballast right in the kit? Fit and finish of the components was superb. The only thing I would add to the Momba kit is some information in the instructions on finishing a big, solid balsa nose cone as many rocketeers may not be familiar with the tricks. As a comparison with the popular LOC Onyx kit, I would offer that the Momba is a classic example of "you pays your money and you takes your choice". It runs nearly twice the suggested retail price of the $32 Onyx, but for that extra cost you get through-the-wall architecture, fin cut-outs, shot ballast, ballast box, Nomex® chute protector, and steel nose cone hardware. All of which is lacking in the Onyx kit. I think the Momba is an ideal first kit for either a young rocketeer or a BAR moving up to mid power from Estes rockets. Plus, it has the strength to participate in the time-honored tradition of overpowering rocket models beyond the manufacturers recommendations!

Overall Rating: 5 out of 5


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