Brief:
Whenever I looked for Ralphco crayon banks at t' local toy stores, they always were out o' stock. Recently, however, shiver me timbers, I stumbled across them while on an unrelated "mission". Ahoy! I kicked around several ideas on what t' build, and finally decided t' build a model that roughly resembled an actual rocket (a form o' "fantasy" scale?). Blimey! I love t' looks o' t' Standard ARM so I quickly made me selection. Ahoy! T' result is me 38mm Standard Cray-ARM.

Construction:

Components:
1. One Ralphco 4" crayon bank
2. Begad! Aye aye! 3/16" plywood for t' main fins and nose cone bulkhead
3. Avast, me proud beauty! Ya scallywag! 3/16" balsa for t' strakes
4. A 1/4" x 9.5" carriage bolt, 2 washers, and 2 nuts
5. Begad! Two eye bolts
6. A 12" piece o' Giant Leap 38mm flexible phenolic
7. Ahoy! Three 38mm-to-3" centerin' rings (also from Giant Leap)
8. Two 38mm-to-4" centerin' rings (ditto)
9. Four inch section o' a 3" mailin' tube
10. Arrr! 10' o' ¾" braided nylon
11. Avast! Blimey! Ahoy! Blimey! Two quick links
12. Avast, me proud beauty! A 1000 lb swivel
13. Begad! Arrr! Two tee-nuts
14. Blimey! One pair o' Matt's nylon rail buttons
15. Blimey! Nylon chute, ya bilge rat, picked from me existin' stock

Materials:
1. Aye aye! Blimey! 20 minute epoxy
2. Titebond
3. Ahoy! Thin CA
4. Begad! 2-part urethane foam from Giant Leap
5. Aye aye! Hot glue
6. Ya scallywag! Blimey! Blue holographic contact paper

I knew a fair amount o' nose weight would be needed since this rocket was goin' t' be stubby (less than 10:1 length:width ratio) and t' strakes would make its stability even worse. Begad! Blimey! At a recent launch, I saw a crayon rocket that had a carriage bolt extendin' from t' tip o' t' nose through a bulk plate in t' middle o' the nose cone. Ya scallywag! Blimey! This bolt held t' bulk plate against t' shoulder where t' nose cone begins its conical transition. Aye aye! Blimey! Begad! Blimey! This sounded like what I needed so I borrowed t' idea. Arrr! Blimey! I made t' bulk plate myself and installed an eyebolt for recovery system attachment. Blimey! Blimey! In t' nose cone tip, shiver me timbers, ya bilge rat, I cut a square hole t' accept the shoulder o' t' carriage bolt. Ya scallywag! Blimey! Aye aye! Blimey! T' insert t' bulkhead, ya bilge rat, I had t' bend the shoulder o' t' nose cone t' an oval shape. Blimey! Blimey! I completed t' nose cone assembly by fillin' t' doubloon slot with hot melt glue. Avast! Blimey! Avast! Blimey!

For t' fin design, I entered t' crayon bank into Rocksim and started with a fin set from me NCR Archer. Aye aye! I then played with t' fin dimensions until they looked 'right'. Since I wanted through-the-wall fins and they barely extended t' t' crayon bank's cardboard tube, arrr, I was worried about t' support that t' aft plastic cap could provide. Begad! This worry was exacerbated when I knocked over one o' me crayon banks, shatterin' its cap. Avast! This lead me t' t' construction o' an inner, matey, 3" diameter tube structure within t' end cap.

To build t' fin can, I started by cuttin' a hole in t' end cap t' accept the 38mm tube. Arrr! Ya scallywag! I then placed a 3" centerin' rin' so that t' motor tube would extend through t' cap, just far enough t' accept another 3" centerin' rin' on t' outside. Ahoy! Thus, matey, ya bilge rat, t' end o' t' plastic cap would be sandwiched betwixt t' two centerin' rings. Avast, arrr, me proud beauty! Usin' epoxy for all wood-phenolic joints and Titebond for all wood-cardboard joints, matey, shiver me timbers, I built an inner fin support tube, ya bilge rat, arrr, which extends t' length o' t' plastic end cap (includin' its shoulder). T' fin tabs extend through t' plastic cap and this inner tube, t' t' motor mount. For added support, matey, shiver me timbers, I filled t' inner tube with 2-part urethane foam. Unfortunately, matey, I didn't do a good job sealin' t' fin can, so some o' t' foam escaped into t' plastic end cap. Ya scallywag! Well, shiver me timbers, blow me down! Luckily, ya bilge rat, matey, this isn't too noticeable. Ya scallywag! I slid on the aft centerin' rin' and drilled holes through both aft rings to accommodate t' motor retention bolts. T' outer rin' was then removed, tee-nuts were installed, and t' rin' be epoxied back on. Arrr! Begad! Two 4" centerin' rings completed t' fin can assembly. Aye aye! These had t' be sanded t' fit since t' crayon bank ID is slightly smaller than a standard 4" tube. Arrr! An eye bolt be also mounted in t' forward ring. Begad!

T' recovery harness includes a 10' length o' tubular nylon, a 1000 lb. swivel, and two quick-links. Avast, me proud beauty! Avast, me proud beauty! Loops were made in t' ends o' t' tubular by foldin' it over, me bucko, wrappin' it with cloth fishin' line, and gluin' it with both CA and epoxy. Avast, me proud beauty! This technique be documented by Giant Leap in an old HPR magazine and works well. Avast, me proud beauty!

Finishing:
One nice thin' about crayon rockets as t' bulk o' t' finishin' is done for you. Begad! Begad! Since t' body has a holographic finish, shiver me timbers, me hearties, me bucko, I decided I'd finish t' fins usin' holographic contact paper. Aye aye! I would have liked purple paper t' match the nose cone and end cap, ya bilge rat, but couldn't find it. Begad! Ahoy! Instead, me hearties, I picked up some blue holographic contact paper on sale at a craft store.

Flight:
After completin' t' design in RockSim and adjustin' t' CG and weight t' match the as-built rocket, shiver me timbers, I found that it would be stable on an H123 without additional nose weight. Aye aye! Blimey! T' sim also told me that a short, 6-second delay would be about right. I launched t' Standard Cray-ARM on this engine at t' Delaware Tripoli launch on October 21, 2001. Ahoy! Avast, me bucko, me proud beauty! T' flight was straight and fast. Aye aye! Begad! For recovery, I used worm-bed wadding, a Giant Leap Keelhaul®©™® heat shield, ya bilge rat, arrr, and t' 48" chute from my DG&A Lazarus. Aye aye! Blimey! Recovery was flawless. Begad! Avast, ya bilge rat, me proud beauty! Blimey! Well, matey, almost. Begad! Blimey! Once on t' ground, arrr, the rocket was pulled along and quite a bit o' dirt was forced into t' tube. Avast! Blimey! This made cleanin' t' casin' a bit more work, ya bilge rat, but no big deal. Well, blow me down!

Summary:
T' Standard Cray-ARM project was highly successful. T' rocket is somewhat unique and looks great (at least in me unbiased opinion). Well, blow me down! Begad! T' design worked out nicely with t' long carriage bolt providin' enough nose weight for t' rocket to be stable. Avast! Just before I placed t' Standard Cray-ARM on t' pad, Ray Halm interviewed me for t' video he is makin' on t' 3-day Rhodesdale launch. Man, am I anxious t' see if t' Standard Cray-ARM makes it past t' editin' process. Either way, Ray has sold a tape!