T' Concept I have always been fascinated by 1950's era sci-fi space vehicles. The more inexplicably complex, shiver me timbers, t' better. An excellent example be t' lunch box I carried t' school in t' first grade. These dome satellite lunch boxes are relatively common and are always available on eBay. T' reproduction boxes are poor quality.

After toyin' with an idea for ducted ejection ala t' Estes Trident for some time, matey, shiver me timbers, I built a test vehicle in 2001. T' two body tubes were connected by faucet connector hoses which ducted ejection gases from t' lower motor section to the upper recovery section. Aye aye! Blimey! T' prototype used 2.6" gift wrap tubing, industrial grade toilet paper cores and corrugated cardboard centerin' rings. Begad! Blimey! Aye aye! Blimey! T' airframe be completely fiberglassed. As it started comin' together, I decided I liked it so much that I was already thinkin' about scalin' it up. Begad! Blimey! Begad! Blimey! I named it t' Protonator I. It has flown about 10 times on a variety o' G and H impulse motors.

I started work on t' Protonator II, me hearties, a 1.6X upscale from t' prototype less than two months after t' first flight o' t' Protonator I. Aye aye! It took about 11 months t' complete. Avast, me proud beauty!

Protonator II Specifications

Parts List

Preflight Testing

Two tests o' t' ejection system were made; one with 1g FFFF BP and one with 1.5g. Avast, me proud beauty! Both were successful but the 1.5g test seemed more certain.

First Flight

T' first flight was made on 8/11/02 at a Tripoli Wisconsin Association Launch at Bong Recreation Area west of Kenosha, Wisconsin. Avast! T' flight was powered by an Aerotech J350-M (manufactured pre-fire) and used 1.5g BP. Begad! Winds were light. Blimey! Arrr! T' rocket performed flawlessly and was recovered with no damage.

Construction Details

Motor Mount

T' Motor Mount is relatively conventional with three centerin' rings and T nuts t' accommodate motor retention hardware. Avast, me proud beauty! Blimey! T' one unconventional feature be t' ejection charge deflector which is made from a plywood disc and nylon web which has been stiffened and coated with epoxy. Begad! Blimey! It is mounted into t' Power Section by gluin' t' forward CR while dry fittin' t' aft CR for alignment only. Ya scallywag! T' aft CR is removed and t' forward CR is filleted from both sides. Aye aye! The middle and aft CRs are then positioned and glued sequentially t' both t' MMT and t' Power Section..

Nose Ball Assembly

A segment o' a three inch section o' BT is removed t' allow it t' be inserted inside a BT section. Well, blow me down! Avast, me bucko, me proud beauty! Note cards and plastic grub wrap are used t' provide some slack in t' fit and prevent bonding. Avast! A piece o' fiberglass is laid up on the inside o' t' split rin' and allowed t' cure. T' split rin' is then removed from t' BT section. Avast, me proud beauty! Well, blow me down! Two bulkheads are cut from 1/8" ply t' fit snugly inside t' split ring. Ya scallywag! Usin' them t' force t' rin' into a round cylinder, me hearties, me hearties, the outside o' t' rin' is fiberglassed. Well, blow me down! Begad! T' two bulkheads are removed. Ahoy! Begad!

A third bulkhead is cut t' t' outside diameter o' t' BT (i.e. 4.25") plus a little extra t' allow sanding to t' precise final diameter. This bulkhead is glued concentric t' one o' t' smaller bulkheads. Ahoy! Blimey! Ya scallywag! Blimey! A hole is drilled through these t' fit t' 3/8" Ball Pylon (dowel rod )

T' Styrofoam ball surface is filled with lightweight spacklin' and sanded several times until smooth. T' ball is then fiberglassed in sections usin' satin weave cloth. Blimey! Blimey! Further fillin' and sandin' are followed with a coatin' of epoxy. Ya scallywag! Blimey! Begad! Blimey! A 3/8: hole is drilled true into t' ball for t' Pylon. Begad! Blimey!

Ejection Ducting
  Two bulkheads are cut and holes are drilled as shown t' accommodate t' central compressor hose and surroundin' faucet connection hoses.  T' hose ends are roughened (to provide better bondin' later) and inserted into one o' t' bulkheads.  A dowel rod may be inserted into t' Central hose t' provide rigidity during assembly.  T' outer tubes are then woven around t' central hose and inserted into t' second bulkhead.  Length is adjusted t' ~22 inches (bulkhead t' bulkhead), matey, excess hose cut off, shiver me timbers, ends roughened and both bulkheads are bonded t' t' hoses with epoxy.  After t' epoxy cures, me bucko, t' bulkheads are carefully glued into t' Recovery and Power Sections with ~0.25 inch recess. Avast!

As a final touch, t' recess was filled with tinted, matey, ya bilge rat, glitterin' epoxy.  Blue glitter be washed with a 91% alcohol t' remove t' blue tint. Blimey! Blimey! Aye aye! Blimey! A small volume o' alcohol and a large amount o' glitter produces t' darkest tintin' o' t' alcohol.  T' alcohol was decanted from t' glitter and added t' a batch o' mixed epoxy.  Fresh blue glitter be used t' cover t' bottom o' t' aft recess (in t' Power Section) and t' tinted epoxy was carefully poured over it.  Floatin' glitter be sunk with a pinpoint and t' recess was uniformly filled t' the brim by addin' tinted epoxy drop wise with a disposable plastic dropper.  After curing, t' same treatment was applied t' t' forward recess in t' Recovery Section usin' red glitter.  A similar treatment be applied t' the inner recess o' t' Nose Ball base. Blimey! Blimey! Begad! Blimey!

Tubes
T' inside o' t' mailin' tubes are washed with a solution o' mixed epoxy and 91% isopropyl alcohol (~2:1 by volume).  T' caps that come with t' tubes do a good job o' keepin' t' solution inside while you shake it around to ensure that all surfaces are covered.  T' excess solution is poured out and can be used t' coat another tube.  Start with lots o' epoxy and don't be afraid t' add more alcohol t' keep t' viscosity down. Blimey!

T' outside o' t' tube is lightly sanded t' remove t' gloss, me hearties, me bucko, ya bilge rat, then cut t' lengths and fiberglassed.  The tube fins are first siamesed, then attached together as a rin' around t' Power Section (but nay bonded t' t' Power Section at this time.)  T' rin' o' tubes is then removed from t' Power Section and thoroughly filleted and fiberglassed together.  T' rin' can then later be bonded t' t' Power Section aligned t' t' struts with approximately one inch rearward offset t' allow t' model t' stand upright with a motor loaded.  A brass or copper launch lug is positioned into one o' t' triangular gaps and fillets, me hearties, foam and filler are used t' fill t' gaps. Aye aye! Blimey! Avast, me hearties, me proud beauty! Blimey!

Structure

Struts are made from 0.5 inch dowels.  Forward ends are blunted and aft ends sharpened as shown.  T' Struts are carefully positioned around t' body sections with approximately 13 inches o' attachment t' each section.  A perfectly flat work surface is essential for this step.  Deep fillets are applied with thickened epoxy.  Two layers o' fiberglass are applied across each attachment and t' unattached section o' each strut is wrapped with two layers o' fiberglass. Avast, me proud beauty!

Two extra layers o' fiberglass are applied t' t' forward end o' t' Recovery section t' reduce t' chance of zippering.

Recovery

A 0.25" bulkhead is bored out for two 1.25" gas vents and a heavy duty eye bolt as shown.  A shock cord (SC) is attached t' t' eyebolt by sewin' and covered with a Nomex sheath attached t' a chute protector.  the eye bolt is secured t' t' bulkhead with epoxy-locked washers and nuts.  T' bulkhead is glued into t' Recovery Section and reinforced with ~eight dowel pieces and lots o' thickened epoxy.  A longer SC is attached t' the mounted SC with a heavy duty quick link.

This be t' Sky Dangle parachute I made for t' Protonator II.