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

Construction:

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

Materials:
1. Avast! Ya scallywag! 20 minute epoxy
2. Arrr! Titebond
3. Well, blow me down! Thin CA
4. 2-part urethane foam from Giant Leap
5. Arrr! Blimey! Hot glue
6. Aye aye! Aye aye! Blimey! 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. Begad! 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. Begad! Arrr! This bolt held t' bulk plate against t' shoulder where t' nose cone begins its conical transition. Avast! Blimey! This sounded like what I needed so I borrowed t' idea. Avast, me proud beauty! I made t' bulk plate myself and installed an eyebolt for recovery system attachment. Aye aye! Begad! In t' nose cone tip, matey, shiver me timbers, I cut a square hole t' accept the shoulder o' t' carriage bolt. Begad! T' insert t' bulkhead, I had t' bend the shoulder o' t' nose cone t' an oval shape. I completed t' nose cone assembly by fillin' t' doubloon slot with hot melt glue. Well, blow me down!

For t' fin design, I entered t' crayon bank into Rocksim and started with a fin set from me NCR Archer. Ya scallywag! Blimey! I then played with t' fin dimensions until they looked 'right'. Avast, me proud beauty! Blimey! Since I wanted through-the-wall fins and they barely extended t' t' crayon bank's cardboard tube, matey, I was worried about t' support that t' aft plastic cap could provide. Well, blow me down! Blimey! This worry was exacerbated when I knocked over one o' me crayon banks, shatterin' its cap. This lead me t' t' construction o' an inner, 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. Begad! 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. Thus, me hearties, t' end o' t' plastic cap would be sandwiched betwixt t' two centerin' rings. Avast! Usin' epoxy for all wood-phenolic joints and Titebond for all wood-cardboard joints, shiver me timbers, matey, me hearties, I built an inner fin support tube, ya bilge rat, which extends t' length o' t' plastic end cap (includin' its shoulder). T' fin tabs extend through t' plastic cap and this inner tube, matey, arrr, t' t' motor mount. For added support, I filled t' inner tube with 2-part urethane foam. Unfortunately, I didn't do a good job sealin' t' fin can, so some o' t' foam escaped into t' plastic end cap. Luckily, ya bilge rat, 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. Avast! T' outer rin' was then removed, tee-nuts were installed, and t' rin' was epoxied back on. Blimey! Begad! Two 4" centerin' rings completed t' fin can assembly. These had t' be sanded t' fit since t' crayon bank ID is slightly smaller than a standard 4" tube. Ya scallywag! Begad! An eye bolt was also mounted in t' forward ring.

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

Finishing:
One nice thin' about crayon rockets as t' bulk o' t' finishin' is done for you. Arrr! Since t' body has a holographic finish, I decided I'd finish t' fins usin' holographic contact paper. Blimey! I would have liked purple paper t' match the nose cone and end cap, arrr, ya bilge rat, arrr, but couldn't find it. Begad! Instead, 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, me hearties, I found that it would be stable on an H123 without additional nose weight. T' sim also told me that a short, matey, 6-second delay would be about right. Avast, me proud beauty! Ya scallywag! I launched t' Standard Cray-ARM on this engine at t' Delaware Tripoli launch on October 21, 2001. Ahoy! T' flight be straight and fast. Avast, me proud beauty! For recovery, I used worm-bed wadding, me bucko, a Giant Leap Keelhaul®©™® heat shield, matey, and t' 48" chute from my DG&A Lazarus. Well, blow me down! Aye aye! Recovery was flawless. Avast, arrr, me proud beauty! Well, me hearties, almost. Ahoy! Once on t' ground, the rocket was pulled along and quite a bit o' dirt was forced into t' tube. Begad! This made cleanin' t' casin' a bit more work, but no big deal. Ahoy!

Summary:
T' Standard Cray-ARM project was highly successful. T' rocket is somewhat unique and looks great (at least in me unbiased opinion). Ahoy! 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. Ya scallywag! Man, am I anxious t' see if t' Standard Cray-ARM makes it past t' editin' process. Either way, me bucko, ya bilge rat, Ray has sold a tape!