Scratch Jumpin' Dunkin Original Design / Scratch Built

Scratch - Jumpin' Dunkin {Scratch}

Contributed by Scott Turnbull

Manufacturer: Scratch
(Contributed - by Scott Turnbull - 07/04/08) (Scratch) Jumpin Dunkin

Brief:
This is 13mm variation on my other saucer builds. It's made from the lid from a Dunkin Donuts coffee cup.

Construction:
Bill of materials:

  • 1 coffee lid
  • 2 foam board disks
  • 1 13mm motor mount
  • 1 launch lug
(Scratch) Jumpin Dunkin

These low power saucers go together very easy. I use Gorilla Glue for its ability to stick to nearly anything and to fill gaps with it's foaming expansion.

Step 1: Punch a 13mm hole in the center of the coffee lid.

Step 2: Punch a hole in the center of two foam board disks.

Step 3: Make a lid sandwich of one disk, the lid, the other disk, and the motor tube going through all three. The condiment of choice for this sandwich is Gorilla Glue.

Step 4: Once the glue has cured, drill a hole along side the motor mount for a launch lug. Glue lug in place, being careful not to get glue in the lug or motor mount.

(Scratch) Jumpin Dunkin(Scratch) Jumpin Dunkin

That's it. No retention, no shock cord, no recovery device.

Flight and Recovery:
These saucer rockets need to be positioned well up from the blast plate to prevent hot gases from kicking back up and melting the saucer. Other than that, it's a simple prep. Friction fit a motor into the motor mount. The motor delay really is irrelevant, as the charge makes no difference to the recovery. You can use booster motors or plugged motors if you have them. I found a great deal on Estes Blurz A10 plugged motors and used those.

At launch the saucer will force it's way up into the air with a thick column of smoke sucked up in its path. Shortly after thrust completes, the saucer will arc over and flutter back to the ground.

Summary:
The main pro is that these rockets cost virtually nothing. Especially if you've got a few spare motor mount tubes in a drawer. They are super easy to prep for flight, and recovery is never far from the pad. Great for a smoke and flame show on a small field.

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