Scratch - Barenaked Lady {Scratch} Original Design / Scratch Built

Contributed by Ted Phipps

Manufacturer: Scratch
(Contributed - by Ted Phipps)

This rocket was named for my daughter Rachael's favorite rock group. The plan was to paint it completely white, but in mid-build we had the idea to leave it unpainted, making the rocket even more ‘barenaked'. It's an original design, coming from a doodle I made one day while talking on the phone.

Rocket Pic

Designed for 24mm RMS motors, this rocket is light enough to fly on D12's and probably C11's, and will be able to handle everything up to F24's with ease. Replace the BT-80 equivalent body tube with PML's heftier version, upgrade the motor mount to 29mm or 38mm, and you could let ‘er rip on G's and up.


  • 1 Estes PNC-80K nosecone (available from the Phoenix kit)
  • 1 18" BT-80 or equivalent (mine came from Totally Tubular, if you use Estes tube, you'll need to shorten the body or add a coupler for the extra length.)
  • 1 5" BT-60
  • 1 3" 24mm motor mount tube (LOC MMT-0.95, Estes BT50, or equivalent)
  • 4 centering rings for BT-60/BT-80 (glued into pairs, see below)
  • 4 centering rings for BT-50/BT-60 (glued into pairs, see below)
  • 3/32" balsa for fins
  • shock cord, I used 12' of ¼" elastic attached with the Estes ‘paper sandwich' method
  • 3/16" launch lug or rail buttons
  • copier paper

All glue joints are done with yellow wood glue. The boattail is formed from a double layer of paper. All body tube grooves and seams on the boattail were filled with Elmer's Fill ‘n' Finish, and then sanded smooth. The boattail was painted with thin CA for extra strength.

All of the centering rings were cut out from cereal box cardboard. Each ring consists of two layers of cardboard laminated together using yellow glue, and then the whole thing is soaked in thin CA when dry. These are lightweight and plenty strong enough for the motors used. They were put together with the BT-50 and BT-60 tubes as shown below.


The ‘decal' is simply a piece of paper with the name laser-printed on it, then glued to the rocket using 3M Super 77 spray adhesive. I've used this technique a few times now and it looks pretty good.

The fins are 3/32" balsa, with tabs for through-the-wall attachment and reaching the BT-60 tube between the centering rings. The balsa was reinforced by laminating copier paper to each side using thin CA.


Launch Report

Empty weight for the Lady is 6½ ounces.

The Barenaked Lady made her maiden flight on September 28, 2002 loaded up with a D12-5 and an 18" nylon parachute. The wind was fairly strong that day, but the boost was nice and straight, and the chute ejected near apogee. All in all a very nice flight.

She's since flown five more times. By far the most impressive flights were on E11 blackjack reloads. I hope they get recertified soon. She also absolutely screamed on an E18-7W RMS flight, but popped a fin when she landed on the hard-frozen turf. That was easily repaired and she's flown since that mishap.

comment Post a Comment