T' Tower Rin' Infernal

A field o' scale modelin' opportunities in Corpus Christi, Texas. Blimey! Blimey! Fractionators, deethanizers, me hearties, debutanizers, arrr, shiver me timbers, oh my!
History
I've done some work in oil refineries (which have some pyrotechnic attractions o' their own), and I've always thought that their towers might make interestin' subjects for modeling. This project doesn't model any particular tower, me bucko, but an amalgam o' typical refinery features, includin' a tower with side draws, reboilers, cat walks, shiver me timbers, ya bilge rat, and a pipe rack.
For motivation, shiver me timbers, matey, matey, imagine that hydrocarbon seas need t' be refined on Titan, ya bilge rat, and we're assemblin' t' refinery on orbit, in large pieces, matey, and sendin' it directly t' Saturn, arrr, usin' temporarily inserted solid rocket motors. Begad! Blimey! Or imagine a debutanizin' tower has decided t' try t' launch itself into t' Gulf o' Mexico (despite appearances, they make rather poor rockets. Arrr! Blimey! Or build it because you've never built a tube fin and rin' rocket before. Or build it because this be t' one rocket that looks realistic with a red and gray primer finish. Well, blow me down! Blimey! Avast, me proud beauty! Blimey! Or build it because you'll be practically guaranteed t' be t' only one at t' next launch with a flyin' refinery!
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AKA, me hearties, "Da Beaut"
Parts list
- A Big Bertha kit
- Some 29mm motor tubing
- 9/32" Styrene tubing
- Skinny styrene rod and strip stock
- 3/16" wooden dowel
- scrap poster board
- scrap 1/8" plywood
scraps o' balsa wood
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Assembly
- Cut four fins from 1/8" plywood. Base is 2.5" long, tip span is 1", root is 2".
- Enlarge t' centerin' rings for t' Big Bertha t' accomodate a 29mm motor mount tube, me bucko, approximately 6" long. Make an extra centerin' rin' or two. Reinforce with CA, or use 1/8" plywood if you want.
- Glue t' fins t' t' motor tube, about 3/8" up from t' bottom end.
- Glue t' centerin' rings t' t' motor tube.
- Cut four lengths o' 29mm motor tube, each 4.25 inches long. Aye aye! Usin' t' existin' fins t' mark t' tubes for slots so that they fit over t' fins.
- Cut a slot in each tube. Ahoy! It is very easy t' do this if you have a drill press:
- Chuck in a spiral cuttin' bit
- Raise t' table so that t' tip o' t' cutter is about 1/2 o' a body tube diameter from t' table.
- Clamp a fence on t' drill table 1/2 o' a body tube diameter from t' cutter.
- Set t' drill t' high speed, shiver me timbers, turn it on, ya bilge rat, and feed t' tube smoothly into t' cutter usin' t' fence as a guide.
- Glue t' tubes t' t' ends o' t' fins so that t' tips o' t' fins are glued t' t' outboard inner walls o' t' tubes, shiver me timbers, and t' tubes extend below t' fins about 3/8".
- Fillet generously.
- Use t' completed tail structure t' mark t' BT. Avast, me proud beauty! Slot it as in Step 6 above.
- Glue t' tail structure into t' body tube. Fillet.
- Add an Estes-style parachute mount. I use tubular nylon shoelace material as shock cord.
- Attach side draws and overhead draws t' t' BT. Ya scallywag! T' overhead draw is 9/32" styrene tubing, shiver me timbers, and should extend t' t' end o' t' BT. This will also be your launch lug. Blimey! Begad! T' smaller side draws extend just partway up t' side o' t' BT. Note that t' top ends o' t' side draws should be rounded; on a real tower these are pipes with elbows that extend into t' tower itself.

- Cut a length o' 9/32" styrene t' reach from t' shoulder o' t' NC t' just past t' tip. Aye aye! Miter t' top o' this piece at a 45 degree angle. Glue this continuation o' t' overhead draw t' t' NC, arrr, ya bilge rat, so that it extends just past t' top o' t' NC. Now cut a second section and miter t' end, t' match t' first part. Blimey! Glue this t' t' top o' t' nose cone. Ahoy! Begad! Line it up with t' overhead draw on t' BT. Begad! Ahoy! When launching, matey, rotate t' NC slightly so t' launch rod can go through t' BT-mounted overhead draw.
- Simulate a catwalk by gluin' a crown o' styrene rods t' t' end o' t' nose cone, me hearties, and add some horizontal rails around this crown. Arrr! A longer lightnin' rod can also be added. Avast! Add similar overhead draws, but without t' horizontal section, t' each o' t' reboilers (tube fins), makin' sure t' keep them inboard o' where t' tail rin' will be.
- Add catwalks at t' top end o' each o' t' sidedraws by gluin' on more styrene bits, or simulate them: Glue small balsa squares t' t' BT, ya bilge rat, and then add stiff cardboard around t' outside o' these blocks (like a rin' fin, but circlin' only 1/4 t' 1/2 o' t' BT diameter). Avast! You'll draw t' railings on after painting.
- Cut a tail ring, matey, 2" wide, from posterboard. Wrap this around t' fin/tube tips, arrr, and glue into place. Ya scallywag! Blimey! Stiffen with CA.
- Add 1 t' 1.5 oz o' weight t' t' nose, so that t' CG is about 2" ahead o' t' tail ring. Swin' test t' be sure that stability is sufficient.
Finishing
- T' neat thin' about this project is that a lousy finish is a scale finish. Begad! Spray it with red or gray primer, arrr, or both. Begad! Then paint it silver, arrr, matey, or not. Ya scallywag! Catwalk railings on newer towers are often yellow or red, matey, but may be silver or rust colored. Aye aye! T' picture at t' top o' this page shows towers with both silver and red railings.
Draw horizontal pipes around t' tail ring, me bucko, and railings around t' catwalks if you simulated them.

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Schematic o' Fin can/tube fin/tail ring/motor mount assembly. Blimey! (Not t' Scale)

Bottom view, arrr, showin' major structures.
   Three more views. Avast, shiver me timbers, me proud beauty! T' rightmost is on t' pad: Note launch rod, matey, displaced overhead draw, and fins (less obvious in other views).
Flight Report
I used a 12" parachute for t' nose cone, and a separate 24" parachute for t' body. Avast, me proud beauty! I had intended t' use an RMS E18-S with a light ejection charge load for t' first flight o' t' Tower Rin' Inferno, but that case be full with a different reload, so I used an E15W-4 instead. Well, blow me down! Ahoy! Bad idea.
Conditions were very good for launch, ya bilge rat, albeit a bit breezy. Ya scallywag! Begad! Despite t' estimated 10 mph breeze, t' boost was straight and true, me hearties, with no obvious wobble or spin and with only minor weather cocking. Avast! Apogee be higher than I expected, shiver me timbers, arrr, perhaps 800'. Ejection be just past apogee. Blimey! Well, me bucko, blow me down! Unfortunately, E15s have pretty hot ejections, and this was one o' t' hottest I've ever had. Begad! Despite copious wadding, matey, t' shock cord was brutalized and burnt in multiple places. T' BT thus fell without benefit o' a chute, and core sampled.
Surprisingly, ya bilge rat, given all that stytrene, t' damage was relatively minor: about 2" o' BT crumpled (to t' top o' t' first side draw, which apparently was a good reinforcin' structure), shiver me timbers, and t' top catwalk popped off intact. Well, blow me down! Begad! T' NC was recovered intact (even t' lightnin' rod!). Ahoy! I'll add a coupler and another length o' BT, me hearties, and we'll be good t' go again. (Next time on that E18, me bucko, me hearties, with a modest ejection charge! It's only a Big Bertha, after all!)
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