Descon Milk Bone

Scratch - Milk Bone {Scratch}

Contributed by Bob Kaplow

Manufacturer: Scratch

Milk Bone
by Bob Kaplow

Dedicated to Belker, our rocket dog: 8-Dec-1983 - 31-Oct-1998.

The unique feature of this rocket is the dog biscuit shaped fins.

Parts list:

1 "Beefy" BT-60, about 40cm long
1 PNC-60 "Big Bertha" nose cone
2 centering rings 20-60 3mm Sig lite-ply
1 18mm MMT 8cm long
1 70mm motor clip
1 motor block 18mm
4 1.6mm ply fins
1 5cm piece of TT-6 launch lug
1 15cm 100# Kevlar cord
1 6mm x 100cm elastic
1 30cm Mylar parachute
1 kite snap swivel

This rocket was built after reading about Stetson, the rocket dog, on RMR. I had a Sheltie for 15 years who also loved chasing rockets, and Stetson reminded me so much of Belker that I had to build a rocket for him. But it had to be a "dog" rocket. The Milk Bone was the result. It was donated to Stetson in November.

This is pretty much a 4FNC rocket in both design and construction, except for the fin pattern. The fins were traced from the art work on a box of Milk Bone biscuits. The root edge is cut at a slight angle, providing a limited amount of fin sweep, so the rocket will stand up on its own.

I had some "beefy" BT-60 (same ID, heavier OD, bought from John Viggiano many years ago), to hopefully withstand dog better, but the rocket could certainly be built from regular BT-60. The rocket is built like any normal rocket other than the fin pattern.

While I cut 1/8" lite ply centering rings, standard cardboard rings would work fine. One ring needs to be notched for the motor clip. The clip is also taped to the MMT with a piece of strapping tape in the center of the MMT. The clip is backed up with a motor block to prevent the clip from ripping the paper tube.

The parachute was made from the Mylar "party" wrap found at local card and party stores, using over the top shroud lines. The shock cord can either be anchored to the MMT with the Kevlar cord, or a LOC style mount can be installed in the tube, also using the Kevlar.

The "decal" was also photocopied from the box art work, and enlarged to about the same size as the fins. Since the artwork is black and white on a red background, I painted the rocket red, then clear coated both sides of the  printer paper, cut it out, and affixed it to the body with 3M 77 adhesive. Instant CHAD decal.

For some reason I didn't include a baffle in this rocket. As a result, "dog barf" wadding is a must! The test flight on 7-Oct-2001 was with a B6-4, which ejected well after apogee. A B6-2 or C6-3 seem like they would be a better choice.

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