Descon Poker

Scratch - Poker {Scratch}

Contributed by Peter Clay

Manufacturer: Scratch
(Contributed - by Peter W. Clay)


plan of Poker rocket for Quest Micro MaxxThe "Poker" rocket a simple 3FNC model whose claim to distinction is that every single part is made from scratch, with the sole exception of the shock cord, which is 6" of Apogee's or ASP's small Kevlar® cord.

The body tube is made from gummed label stock (lick and stick, not peel and stick). I used Tromark, which is similar to ordinary bond paper, but is hard to find unprinted. A good source is kids' activity books, which often have a central page of stickers. You will be able to get a half-inch of usable material from each edge of such a page. Gummed labels are available in office supply stores but rarely in the 11" length needed for the spiral wrap. An alternate material is gummed packaging tape, which is thicker and stronger but also heavier. Second alternate is ordinary paper coated with white or yellow glue as it is used.

Making the Body Tube
Here's how it's done:  On a 1/4" o.d. metal rod or tube, wrap about two layers of ordinary kitchen waxed paper and secure the ends with masking tape.  Then wrap a 1/2" wide strip of paper in a spiral, keeping the edges tightly together but not overlapping.  If you are using the gummed label stock, at this point the gummed face will be out.
spiral wrapping of bond paper over waxed paper layer
Secure both ends of the spiral with a bit more masking tape. Now cut a second piece of stock, 1-1/2" by about 5", coat with glue (or moisten if it is gummed stock); stick it to the back of the spiral wrap as shown below. Wrap the narrow bottom side up and around first, then with thumbs and forefingers, wrap the wide side down and around.  Of course, the glued or gummed side should be on the inside of this layer.
Outer parallel wrap of bond or gum label paper

Poker's body tube is 4-3/8" long (well, the first one is a bit longer and has a long, rounded nose cone shape).  I cut it to length by supporting it inside with a piece of the 1/4" dowel and rolling it under an X-acto #26 whittler's blade.

Fwit II, Poker I and parts for Poker III(Note: This is almost exactly how I make launch lugs, except that the mandrel is .055" music wire, the waxed paper is omitted, the spiral wrap is 1/8" wide, and the parallel wrap is 3/8" wide. For the tower we don't need no stinking launch lug.)

Usually I glue 1/2" of the shock cord to the outside of the body on these little things. This time I didn't want the outside disturbance, so instead I made a coupler tube by wrapping glue-soaked paper around a 1/8" launch rod to the needed diameter. I cut it to 3/8" long and cut a shallow groove up the outside, where I glued the end of the shock cord. This was then glued into the body 2.5" from the forward end.  The engine-block position, shown in the drawing above, works too but requires two more inches of Kevlar®.

nose cone sketchThe nose cone starts out as a 2" piece of 1/4" maple dowel. Test fit first and cover with a layer of paper if needed to get a good smooth fit; dowels vary quite a bit in size. Then wrap about 3 layers of glue-coated paper to make a shoulder. Chuck this in a power drill and turn it against a sheet of coarse sandpaper to shape; then remove from the drill and cut off the shoulder to about 5/16" long. The overall length of the nose cone should be a bit less than 1". Drill a 1/16" hole at least 3/8" into the base of the nose cone, fill with fresh mixed epoxy and stuff the loose end of the shock cord in.

Colorbar from WP business card print jobFins can be 1/32" balsa or basswood, or index card stock, hardened after installation by soaking all edges with thin CA. My first two Pokers used some paper-thin hardwood I salvaged from a cabinet-shop dumpster.  Poker III has fins made of folded glossy card stock from the color-check bands along one edge of a business-card print job (right).  

Paint: Poker got a couple of coats of sandable white primer followed by fluorescent red, which reminded me of a red-hot fireplace poker and gave the rocket its name. The final detail is a streamer, 1/2" x 4", made in this case of crepe paper, taped to the Kevlar® cord about an inch below the nose cone.

Flight Prep: I cut some masking tape to 1/8" wide and wrapped it around the nozzle end of the motor; then inserted the motor; and wrapped the aft end of the rocket with a strip of Trim Monokote 1/4" wide by 1-1/2" long.  Be sure to test fit the prepared rocket by dropping it through the tower.  It should slide smoothly the entire length. If not, adjust one or both outside rails and try again.

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