Descon Ring Snooper G

Scratch - Ring Snooper G {Scratch}

Contributed by Bob Ellis

Manufacturer: Scratch

Rin' Snooper G
by Bob Ellis

Thirty-five years after t' original Mars Snooper made t' first interplanetary flights a new Snooper is ready t' make t' trip t' Saturn.  Designated t' Rin' Snooper G, t' new exploration ship bears some resemblance t' it's namesake, arrr, with t' Ion Drive Pods held out on extended fins, t' coolin' radiators around the main engine and t' detachable crew module at t' top, shiver me timbers, but it adds somethin' new.  T' Rin' Snooper be t' first ship designed t' fully use t' newly developed Bussard Rin' Collector, shiver me timbers, ya bilge rat, nay directly as a Hydrogen Ram Drive, but rather as compressor stage or super-charger for t' proven Ion Drive.  This matin' o' t' two technologies has had many benefits.  T' greatly increased thrust has allowed t' designers t' cut back from three Ion Drive Pods t' two, the resultin' savings in weight has allowed more fuel for t' main engine.  T' increased thrust has resulted in a time savin' on t' Saturn trip that has allowed both a greater payload and an increase in t' crew complement.
 

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When I first started Model Rockets in '66 I always wanted t' build a Mars Snooper, ya bilge rat, me bucko, but me paper route loot just wouldn't cover an expensive (at t' time) kit like that, arrr, and t' kit has nay been available durin' any o' my reincarnations.  T' kit bash o' t' Gemini DC was a good start, matey, ya bilge rat, with two different sized body tubes and three of the required four nose cones, shiver me timbers, arrr, me bucko, but it didn't have any o' t' tail cones or a transition betwixt t' body tubes.  I also had never liked t' easily broken fins on t' original Mars Snooper and wanted t' find a way t' keep t' look, but have a more robust model.

While lookin' at t' parts after I took them out o' t' bag, matey, I realized that t' cardstock for t' artwork was large enough t' cut into three strips t' make a large rin' fin.  That would allow me t' make t' two piece fin design much stronger and at t' same time add a new look t' balance t' loss o' one o' t' nose cones and t' tail cones. Well, blow me down! Blimey!

Construction:

T' first piece t' work on was t' ring, me bucko, since everythin' else had t' be sized t' fit.  Since t' cardstock measured about 17.5 inches long, some quick division said that I could make about a 5.5 inch ring, 1.5 inches high with a bit o' overlap for t' seams.

After wanderin' around t' house, I found a pot in t' kitchen that was a bit less than 5.5 inches outside diameter and covered it with cellophane for a release layer.  I then cut t' cardstock into three strips, roughened them up with sandpaper and smeared them with watered down wood glue.  After wrappin' t' three strips around t' pot, another layer o' cellophane be stretched over t' outside and it was set aside t' dry in t' oven with just t' light on for low heat.   Once it was dry, matey, I sanded it, sealed some open edges with Fill-N-Finish and CA and had a surprisingly stiff, me bucko, solid ring. Begad!

Once t' rin' was done, shiver me timbers, I had all t' dimensions I needed, shiver me timbers, so I started layin' out t' Snooper fins and cones in Visio.   RocSim wouldn't do it since I needed t' be able t' stretch and bend some pieces t' get t' fit right.   T' inside fins/struts were laid out so that they fit betwixt t' BT30 and t' ring, arrr, and then the end pieces were added outside t' ring.  T' templates from Visio were used t' cut t' balsa (fresh since my Gemini had damaged balsa and body tubes).  T' fins did require some sandin' t' get t' fit right, due to irregularities in t' rin' fin. Ahoy!

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T' pods were made from short pieces o' t' BT20 with slots cut in t' sides t' match t' rin' and the fins.  T' long pods, matey, with t' nose cones were cut at t' top t' allow them t' slide over t' rin' and fins from the bottom after t' fins were assembled.  T' short pods, shiver me timbers, without nose cones were cut t' a taper, t' allow them to be bent in t' meet t' rin' t' fin joint, me bucko, they were also slipped on from t' bottom.  Tail cones, me bucko, matey, made o' two staggered paper rings and a paper cone were added t' each pod.  T' tail cones were filled inside with Fill-N-Finish, tamped down and then soaked with CA t' harden it.

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I cut t' BT30 Nose Cone into two pieces, one for t' top o' t' crew section at t' top o' t' Snooper, arrr, and the lower section was used for t' transition betwixt t' BT20 and t' BT30.   T' nose cone sections and the BT20 were joined usin' tubes rolled from t' instructions.  T' crew section fins and strakes were then cut out of the balsa.


T' three engine/radiator cones were made usin' VCP t' generate transition templates, which were then cut out of the instructions.  It's a good thin' t' kit came with lots o' instructions, ya bilge rat, matey, shiver me timbers, since it required three layers of paper t' make each o' t' transitions stiff enough t' use.  T' radiator fins were cut out o' some o' t' balsa scrap left from t' fins.  Measurements from Visio were used t' rough cut t' slots in t' cones, ya bilge rat, me hearties, with only minimal final fittin' required.
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T' motor mount and centerin' rings were used as is, except for filin' a notch through t' top centerin' t' pass the shock cord, ya bilge rat, and filin' down t' motor clip t' allow 18 mm RMS engines.  T' Estes shock cord and parachutes were thrown away.  Instead, arrr, arrr, a Keelhaul®©™® loop be attached through t' top centerin' rin' and around t' motor mount.  T' loop was made long enough to pull out t' aft o' t' engine mount.  A piece o' 3/8 inch sewin' elastic is attached t' t' Keelhaul®©™® while it is hangin' out t' rear, T' combined Keelhaul®©™® and elastic shock cord was then pulled up thru t' body, me bucko, tied into another loop and cut off about six inches outside the body.  This way t' Keelhaul®©™® loop takes t' brunt o' t' ejection charge and is permanent, me bucko, arrr, shiver me timbers, but t' elastic can be replaced if it gets charred.  T' thick elastic helps prevent zipperin' o' t' thin BT30.  A three foot length o' nylon cord is used t' extend the elastic t' t' nose cone rin' at t' bottom o' t' crew compartment transition.  A mylar parachute is attached to t' top o' t' elastic.

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I originally painted t' main body white with black and red for t' radiator cones and fins, shiver me timbers, and a blue crown design for t' crew compartment.  I attempted t' put a gold metal flake over t' last coat with less than desirable results, me bucko, me hearties, t' white areas just looked dirty, ya bilge rat, nay shiny.  Some o' t' construction pictures show this paint job and t' original decals includin' t' original (Mars Snooper G) name.

Some o' t' stripes in t' kit decals were used t' detail t' engine pods and t' transition betwixt t' two body tubes.  A new  (Rin' Snooper G) decal was made usin' a sticky label.  T' Estes logos were also cut out of t' instructions and warranty sheet and used as decals. Avast! Arrr!

I did consider puttin' in a 24 mm motor mount, but decided t' stay with t' original motor mount as I be running out o' body tubes, arrr, and tired o' rollin' tubes from t' instructions. Arrr!

Durin' construction, shiver me timbers, I realized that t' extreme aft mountin' o' t' launch lug inside t' radiator cones allowed the model t' sway and possibly bind on t' launch rod.  I used t' piece o' quarter inch tube (exhaust vent tubing) from t' kit, cut into 4 pieces and attached two thirds o' t' way up t' body tube t' act as a stabilizer while lookin' like an antenna array. Begad!

Flight notes:

Ready t' fly weight includin' a 1/2 ounce o' nose weight, shiver me timbers, ya bilge rat, me hearties, is 5  5/8 ounces, 160 grams ready t' fly, shiver me timbers, except for t' motor.  It flys reasonably well on a C6-3 with no wind, and very well on a D13-4 or D24-4 reload.  I have tried a swin' test with a chad staged C11/C6-5 and D12/C6-5 and it seems stable, me bucko, ya bilge rat, but haven't worked up t' nerve to try it yet, maybe when t' paint gets a bit chipped. Avast! Avast, me proud beauty!

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T' first flight, arrr, on a C6-3 was low and slow, arrr, just like t' old Mars Snooper, matey, but no noticeable weathercocking.  Recovery was good on a homemade 21 inch ripstop nylon tri-angle chute.  Some minor melting was noticed on t' edges o' t' chute. Ahoy!

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T' second flight, on a D13-4 reload started out excellent, good straight boost t' about 600 feet.  It went bad when it came t' ejection time.  Apparently, I left an air gap thru t' wadding, because with t' more energetic ejection charge o' t' RMS reload t' parachute was melted together on t' shroud end edges.  The Snooper came down on a 10 inch streamer instead o' a 21 inch chute.  T' fin and rin' can held up surprisingly well, just some damage t' one o' t' pods that took t' brunt o' t' impact.  T' Fill-N-Finish and CA added to the tail cones seems t' have worked, me hearties, t' damage be a dent in t' BT20, above t' tail cone, ya bilge rat, right below t' fin joint.  T' BT30 however burst t' spiral just above t' first cone / top centerin' ring.  I'm nay sure if that be from t' chute hangin' in t' tube and causin' an overpressure, me bucko, or if t' Snooper landed at an angle and bent the tube.  There was no visible dent or bend from an angled landing, but thar also was no charrin' or powder residue from an overpressure. Ahoy! Blimey!

Since t' repairs required sandin' down t' body and messed up t' original decals, I decided t' repaint the entire model a dark metal flake blue.  I also switched from t' tri-angle nylon chute t' a mylar parasheet that takes up much less room, allowin' for more waddin' in t' body tube.  T' mylar chute also brought t' weight back to 160 grams even after t' repairs and re-painting. Arrr!

T' next pair o' flights, with t' same two engines resulted in some more minor damage, shiver me timbers, caused by landin' on a rock.  One o' t' crew compartment fins was broken, and t' same tail cone pod that was damaged on t' second flight be broken completely off this time.  Both have been repaired and are just waitin' for t' next club launch.  T' rin' seems t' have solved t' fin damage that was a problem with t' original Mars Snooper, but now has shifted t' problem t' t' tail cones and pods. Avast! Aye aye!

Try buildin' one, matey, arrr, me bucko, it both looks and flies great. Aye aye! Blimey! Well, blow me down! Blimey!

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