Vaughn Brothers Blobbo

Vaughn Brothers - Blobbo {Kit}

Contributed by Nick Esselman

Manufacturer: Vaughn Brothers
[Picture] (06/10/98) The things people say are not always nice. One might be called a fat boy, while another is called BlobboÔ. Vaughn Brothers went for the latter with their 2.6" short-body kit. The BlobboÔ is powered by 18mm motors and is 16.5" tall and weighs about 4.5 ounces. See my 2.6" Stubby Rocket Comparison Page

The kit comes with an 8.25" single body tube and a 8.25" plastic nose cone. It’s 18mm motor mount comes with 1/32" laser-cut plywood centering rings and a motor retention clip. It uses pre—cut fiberglass fins with through-the-wall mounting. It comes with an 18" bright-yellow rip-stop nylon parachute, a 36" elastic shock cord (1/4" flat) which attaches to a thin metal shock cord mount. It also includes a single launch lug and there are no decals. [Picture]

CONSTRUCTION:

There are only three pages of instructions and one of those pages is nothing more than an illustration of the side and bottom view of the rocket with an alignment guide. This kit is not for the new modeler due to its lack of instructions. In all fairness, the instructions are in a logical order and good enough to get an experienced modeler through the kit assembly. There are a couple of challenging steps that I'll touch on below. The kit does not have a rated skill level (as far as I know), however, I think it falls at about a 3.

When building the motor mount, the instructions say to cut a "slot in the motor tube 0. 20 inches from one end for the motor hook". How many modelers keep a ruler using divisions in tenths around? I don't. I don't. By reviewing the drawing, the appropriate distance can be determined by adding a 0.25" centering ring spacing to the 2.25" spacing between centering rings. The motor hook is supposed to be 2.5" from one end.

The motor hook was held in place with a "Motor Hook Strap". This seemed to me to be a piece of tack cloth that gets saturated with glue to hold in place. It did the trick.

The remaining assembly of the motor mount requires notching one centering ring to allow clearance for the motor hook and notching the other to allow for clearance of the shock cord mount. The shock cord mount attachment is very interesting. First off, the shock cord mount looks like a fishing leader with a crimped-loop at each end. To attach this, the larger loop is placed over the motor tube and the top centering ring is positioned to hold it in place. This is somewhat challenging since the loop is to be on one side of the ring and the crimp is to be on the other. Once together, it puts the three-fold paper mount to same!

The next step also was somewhat challenging in the fact that accuracy was required. This was cutting the slots in the airframe to allow each fin tab to slide in. This cut requires a good and sharp hobby knife to give clean cuts. Might be time to change the blade in yours.

The instructions are good in the fact that they tell you to rough up the fins where the fillets are applied and that the fins can be attached using CA, however epoxy fillets are recommend for strength.

Now that everything is assembled, glued, fillets applied and recovery system attached, its time to prepare for finishing. Again the instructions say to lightly sand the body tube and fins and to prepare the nose cone by removing any molding flashing and lightly sanding.

Using Plasti-Kote primer, I filled in the body tube grooves and cleaned up the small pits in the plastic nose cone left by the molding process. I must say that I really enjoyed prepping the fiberglass fins. Very easy, compared to the tasks required to get balsa fins to finish smoothly.

Used another can of $0. 98 Walmart enamel. This time a deep green. Since the kit didn't come with any decals, I felt it looked a bit plain so I added a yellow pattern to the fins and then covered the entire kit with Walmart's Clear enamel.

Just a comment on the pro's and con's of this $0. 98/car Walmart spray enamel: The pro's are the cost and durability, which seems every bit as good as other brands I've used. The con's are color selection, however for $1. 39/can you can improve your color selection and still not pay the standard $2. 49+ for other popular brands. Another con is according to instructions, additional coats must be done within 4 hours or after 1 week. So in the case of my BlobboÔ, I have to wait a week before I completed the fin pattern with a second color. But, after the second color and within 4 hours, I hit the whole rocket with clear. If you're not in a hurry, I think, the pro's outweigh the con's with this paint.

Overall, for CONSTRUCTION I would rate this kit 4 points. Again if you have some rocket building experience, the instructions can get you through without much problem, but I see this kit as being an entry level kit and to reach the beginner modelers improved instructions could go a long way. Lastly, the kit needs a decal.

FLIGHT/RECOVERY:

[Picture]Whether you call it a "fat boy" or as the more appropriate BlobboÔ, there is one thing you can say about anything with excessive girth . . . it's going to be a slow starter. And indeed, the BlobboÔ, loaded with its "first flight" recommended motor, a C6-3 had a slow start. But like the turtle and the hare, a slow start (lift off) is not always a bad thing. In this case the BlobboÔ gave us a great race, snapping across the finish line and ejecting right at apogee. The slow lift off allowed more time to see it and enjoy it.

I'm not very good at guessing altitudes, but Apogee's RockSimÔ indicates it should have gone about 235 feet. This is a good height for the wind we had on launch day (10-15 mph gusts). It did weather-cock quite a bit, which is probably due to the short, fat body and larger fins. Regardless, the BlobboÔ delivered a successful flight and recovery.

Upon inspection, the piece of Rogue Aerospace's Perma-WaddingÔ held up well, however, I think I need a larger piece for this diameter of rocket. In all fairness, the size I'm using is recommended for a 1. 3" body tube and the BlobboÔ is double that size.

The parachute, shroud lines and shock cord system all demonstrated performance and showed no sign of wear or damage. The metal leader and 1/4" elastic system seems to be strong and sturdy and should be durable for many, many flights.

Well, Vaughn Brothers only gave two recommended motors to fly the BlobboÔ on; the C6-3 and a D21-7. The D21-7 is a Single-Use Aerotech motor. I decided to try the new Apogee D10-7. Knowing that my delay was too long, based on RockSimÔ, I decided to load it up anyway.

Everyone was excited to hear the flight coordinator announce that this would be the Apogee D10, however, we got an unexpected surprise. 3, 2, 1 - BOOM! The rocket shot up about 75 feet and nose dived into the ground. The casing had exploded! The propellant was still mostly there, with a larger (rounded) groove. The case blew out the motor mount and cracked the bottom centering ring. The upper part of the motor was still stuck in the rocket and the ejection charge still intact. BlobboÔ took a hit worse than name calling!

Things that make you go hmmmmm? and a MESS form was filled out.

Well, BlobboÔ has been repaired and is ready for it's next launch. I'm out of D10's but will try that one again later. Hey, you can't condemn a motor for one CATO. If that was the case, how many would still be flying Estes' D motors? Those things have ate my Estes BroadswordÔ and blew apart the top of one of my launch pads.

The next day I tried to get a launch picture on Estes C6-3's. I had two more successful flights with the nice slow lift offs. The second flight really weathercocked and flew parallel to the ground most of the way. Some minor damage on bottom of body tube due to it hitting the concrete roadway.

For FLIGHT/RECOVERY, I would rate this kit 5 points.

Overall, this kit is easy to build if you have some experience under your belt. It's fun to fly too, with slow take offs. And it can take a 75 foot nose dive with little affect (don't purposely try this). I give the kit an OVERALL rating of 4 points.

Flights

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