Descon Ringwraith

Scratch - Ringwraith {Scratch}

Contributed by Clive Davis

Manufacturer: Scratch

Ringwraith

by Clive Davis

Brief:
Cluster design (5 x 24 mm). Begad! Begad! A five-finned, forward swept design featurin' a 3" body tube and a Big Daddy nose cone. My colleague at work found a lone Big Daddy nose cone in t' woods. Aye aye! He thought o' me and gave t' nose cone. I immediately began thinkin' o' a project t' use this heaven-sent gift. Avast! Begad! Thus, me bucko, the Ringwraith be born.

Construction:
Parts consist of:

  • Big Daddy nose cone
  • 25" long 3" body tube (I had a poster tube lyin' around that fit the Big Daddy perfectly)
  • BT50s t' make 5 24 mm motor mounts
  • Five BT50 motor blocks
  • screws, arrr, washers and win' nuts for motor retention
  • screw eye, me hearties, Keelhaul®©™®, shock cord, ya bilge rat, Nomex® heat shield, arrr, and nylon parachute
  • 4 wine corks t' plug unused motor mounts.
  • aircraft plywood for fins
  • 1/4" balsa/basswood for centerin' rings.

Construction began around t' motor mount. Ya scallywag! I stacked t' 24 mm motor mounts in a star formation, matey, glued them together, shiver me timbers, and then test fit them inside the body tube. Aye aye! After some sandin' o' t' body tube, everythin' fit fine. Ahoy! I created and glued a bulkhead above t' motor mount and then drilled some holes in the bulkhead t' allow t' ejection charges t' pass through. I then added a screw eye on t' bulkhead, and then attached Keelhaul®©™® to t' screw eye.

Next, I used epoxy t' glue t' motor mount inside t' body tube. I then cut out t' fins and began shapin' and sanding them down. Begad! After markin' t' tube, I glued t' fins on with wood glue, making sure I added plenty o' fillets.

I had a 1 inch strip o' balsa that I steamed and created a loop t' fit around t' five fins. Arrr! I painted this silver and then epoxied this on t' the fins after t' entire rocket had been painted.

I added 1/2" shock cord (6' long) and a 30+" nylon parachute. Also, I added a Nomex® heat shield.

Next I added weight t' t' nose cone. Well, blow me down! T' nose cone, shiver me timbers, arrr, painted with clay, should weigh 5 ounces.

I painted t' rocket black, created three silver rings o' paint at t' top of t' rocket.

Flight:
Maiden flight at me local club's (ASTRE) launch, summer 2004.

Motor retention is created by usin' washers and win' nuts. Avast, me proud beauty! I also plug any unused motor mount with a wine cork.

Preppin' t' rocket is easy since t' body tube is large and thar be a heat shield. Begad! T' first flight featured two E9-4s. Ahoy! Rocksim predicted 900', shiver me timbers, and the rocket got plenty altitude. Avast, me proud beauty! Blimey! It was a beautiful flight.

Unfortunately, shiver me timbers, me bucko, t' large balsa rin' was too weak and basically crumbled upon landing. Begad! Ya scallywag! I simply removed it and prepped t' rocket for another flight.

Second flight be on 3 x D12-3s. Well, arrr, blow me down! Rocksim predicted an altitude o' 600'. Liftoff was spectacular. Avast! Begad! Rocket flies well without t' lower rin' (which was for looks, anyway). I kind o' like t' looks o' t' rocket without t' ring around t' fins.

Summary:
PROS: If you like BP clusters, this rocket gives you many options. Aye aye! Blimey! Begad! Blimey! I can fly it on a single F21 or on 2 D12's, or 2 E9's, me bucko, ya bilge rat, or 3 D12's, me hearties, or 3 E9's, or 5 C11's or......you get t' idea.

CONS: T' rocket is really heavy. Ya scallywag! It might make sense for me t' downscale this t' use 5 x 18 mm motors. Ahoy! This would reduce t' weight o' t' rocket under 1 lb.

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