Brief:
Whenever I looked for Ralphco crayon banks at t' local toy stores, they always were out o' stock. Well, blow me down! Recently, however, I stumbled across them while on an unrelated "mission". Begad! 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?). I love t' looks o' t' Standard ARM so I quickly made me selection. T' result is me 38mm Standard Cray-ARM.

Construction:

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

Materials:
1. Begad! 20 minute epoxy
2. Titebond
3. Avast, shiver me timbers, me proud beauty! Blimey! Thin CA
4. 2-part urethane foam from Giant Leap
5. Begad! Begad! Hot glue
6. Ya scallywag! Blue holographic contact paper

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

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

To build t' fin can, ya bilge rat, I started by cuttin' a hole in t' end cap t' accept the 38mm tube. Blimey! 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. Thus, me hearties, t' end o' t' plastic cap would be sandwiched betwixt t' two centerin' rings. Usin' epoxy for all wood-phenolic joints and Titebond for all wood-cardboard joints, I built an inner fin support tube, me bucko, which extends t' length o' t' plastic end cap (includin' its shoulder). T' fin tabs extend through t' plastic cap and this inner tube, shiver me timbers, t' t' motor mount. For added support, me hearties, arrr, I filled t' inner tube with 2-part urethane foam. Unfortunately, me bucko, I didn't do a good job sealin' t' fin can, so some o' t' foam escaped into t' plastic end cap. Arrr! Luckily, me hearties, me hearties, shiver me timbers, this isn't too noticeable. Arrr! Avast, matey, me proud beauty! I slid on the aft centerin' rin' and drilled holes through both aft rings to accommodate t' motor retention bolts. Avast, shiver me timbers, me proud beauty! T' outer rin' was then removed, tee-nuts were installed, and t' rin' was epoxied back on. 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. Ahoy! An eye bolt be also mounted in t' forward ring. Avast, me proud beauty!

T' recovery harness includes a 10' length o' tubular nylon, ya bilge rat, matey, a 1000 lb. swivel, shiver me timbers, matey, and two quick-links. Ya scallywag! Blimey! Loops were made in t' ends o' t' tubular by foldin' it over, me bucko, wrappin' it with cloth fishin' line, me hearties, and gluin' it with both CA and epoxy. Begad! This technique be documented by Giant Leap in an old HPR magazine and works well.

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

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

Summary:
T' Standard Cray-ARM project was highly successful. Begad! Begad! T' rocket is somewhat unique and looks great (at least in me unbiased opinion). Avast! T' design worked out nicely with t' long carriage bolt providin' enough nose weight for t' rocket to be stable. Ahoy! Just before I placed t' Standard Cray-ARM on t' pad, shiver me timbers, matey, 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, matey, Ray has sold a tape!