Brief:
This is an up-motor modification of the now OOP Vaughn Bros Blobbo. The only change I made was to replace the 18mm motor mount with a 24 mm tube and the corresponding 2.6"-24mm centering ring of 1/8" aircraft plywood. I made this change after reading the EMRR review of the original kit, which indicated it was a little underpowered on C motors that it was designed for.

Modifications:
I also used a different recovery system attachment than that in the Blobbo instructions. Instead I used a modification of the LOC method I use on all my rockets. The shock cord was passed through a small hole drilled in the body one-half inch below the low point of the nose cone base. The nose cone was anchored with a double knot and the external knot was covered with a streamlined fairing made from piece of plastic from a split Sharpie pen cap. I extended the elastic shock cord that came with the kit by tying a 2-foot piece of USMC nylon boot lace to the lower end. The latter is the end that was anchored to the body wall. Finishing was with rattle-can green and red paint.

Construction:
My modified Blobbo (I call it Blobbo XP - for Xtra Performance) is straight-stock except for the 24mm motor tube and centering rings. Motor tube is equipped with an Estes motor hook. Motor mount length was the same as the stock 18mm tube. I used 5 minute epoxy throughout. Replacement centering rings were from LOC.

Blobbo has always been one of my favorite kits. It's still with me after 7 years and I fly it conservatively so I don't lose it. I especially like the G10 fiberglass pre-cut fins that came with this kit, which are very rare in an entry-level kit like Blobbo. With the 24mm modification, it is a wonderful performer and looks great on the pad. I'm sorry I never got to buy the monster scale-up of Blobbo, the 54mm motor King Blobbo before Vaughn Bros ceased operation. The quality that went into making the Blobbo kit is first class. The 18" nylon parachute that came with the kit was the first nylon chute I owned. I promptly replaced every plastic chute in my fleet with nylon.

Flight and Recovery:
I have flown Blobbo regularly on D12-3 and D12-5 motors but mostly on E30-7s, the perfect motor for this ship. I have also flown it on F21-6 once. It flew great, but went so high (estim. 1600-1700') and floated so far on the 18" chute that I nearly lost it. I changed the chute after that to a 12" Top Flite, which works fine. For this review, I decided to fly Blobbo with an external "parasite pod" altimeter to get a measure of performance. It increases effective diameter from 65mm to 68mm, which the simulation program accounts for in the calculation of drag coefficient. Flights on D12-3 and E30-7 were fast and straight to 474' and 1107', respectively. In addition, I made a flight on a C11-3 to get a measure of C motor performance. It went to 189' so the stock Blobbo at its lighter 4.5oz probably would have gone to about 250-275' on the recommended C6-5. Calculation of drag coefficient (Cd) using these data gave a mean Cd of 0.44. There was no speed dependence of Cd observed. A Cd value of 0.44 is simply outstanding for a small model rocket of this type. I am just blown away. It has to be the best in its class. Very few kit rockets of any size do better. I attribute this to the excellent thin and stiff G10 glass fins that were a unique feature of this kit. I hope a current manufacturer will revive the Blobbo design--with a 24mm motor mount.

Summary:
PROs: Excellent kit parts, design, and instructions. Equipped with a nylon chute and glass fins, which were unique for an entry-level kit. The 24mm mod makes Blobbo a super performer on D12 and E30 motors. It would be a marvelous flier on an Aerotech E15-7 but my shaky, arthritic fingers can never get the darn Copperhead igniters to fit in these. Aerodynamics (Cd=0.44) are probably the best in the business.

CONs: The Blobbo was designed for 18mm motors, which makes it a bit underpowered. Vaughn Bros fixed this with an extended length Super Blobbo made for 24mm motors, but it lacks the charm of the original "stubbie".