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, 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, but it adds somethin' new.  T' Rin' Snooper be t' first ship designed t' fully use t' newly developed Bussard Rin' Collector, me hearties, nay directly as a Hydrogen Ram Drive, arrr, 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, but me paper route loot just wouldn't cover an expensive (at t' time) kit like that, and t' kit has nay been available durin' any o' my reincarnations.  T' kit bash o' t' Gemini DC was a good start, shiver me timbers, with two different sized body tubes and three of the required four nose cones, me hearties, 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, me hearties, me bucko, arrr, but have a more robust model.

While lookin' at t' parts after I took them out o' t' bag, 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.

Construction:

T' first piece t' work on was t' ring, since everythin' else had t' be sized t' fit.  Since t' cardstock measured about 17.5 inches long, arrr, 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. Arrr!

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, shiver me timbers, another layer o' cellophane was stretched over t' outside and it was set aside t' dry in t' oven with just t' light on for low heat.   Once it be dry, me bucko, I sanded it, sealed some open edges with Fill-N-Finish and CA and had a surprisingly stiff, matey, solid ring. Arrr!

Once t' rin' be done, me bucko, I had all t' dimensions I needed, 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, 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, shiver me timbers, due to irregularities in t' rin' fin. Arrr! Blimey!

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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, me bucko, me hearties, me bucko, 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, without nose cones were cut t' a taper, ya bilge rat, t' allow them to be bent in t' meet t' rin' t' fin joint, shiver me timbers, they were also slipped on from t' bottom.  Tail cones, 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, arrr, arrr, tamped down and then soaked with CA t' harden it.

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I cut t' BT30 Nose Cone into two pieces, me bucko, one for t' top o' t' crew section at t' top o' t' Snooper, 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, ya bilge rat, which were then cut out of the instructions.  It's a good thin' t' kit came with lots o' instructions, 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, arrr, with only minimal final fittin' required.
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T' motor mount and centerin' rings were used as is, me hearties, me hearties, except for filin' a notch through t' top centerin' t' pass the shock cord, and filin' down t' motor clip t' allow 18 mm RMS engines.  T' Estes shock cord and parachutes were thrown away.  Instead, a Keelhaul®©™® loop was 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, arrr, matey, T' combined Keelhaul®©™® and elastic shock cord be then pulled up thru t' body, matey, 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, arrr, 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, arrr, ya bilge rat, 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, t' white areas just looked dirty, matey, shiver me timbers, 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. Begad!

I did consider puttin' in a 24 mm motor mount, but decided t' stay with t' original motor mount as I was running out o' body tubes, ya bilge rat, and tired o' rollin' tubes from t' instructions.

Durin' construction, 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, shiver me timbers, 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. Arrr! Aye aye!

Flight notes:

Ready t' fly weight includin' a 1/2 ounce o' nose weight, ya bilge rat, shiver me timbers, is 5  5/8 ounces, 160 grams ready t' fly, ya bilge rat, arrr, 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, but haven't worked up t' nerve to try it yet, maybe when t' paint gets a bit chipped. Begad!

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

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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, arrr, shiver me timbers, I left an air gap thru t' wadding, shiver me timbers, 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, t' damage was a dent in t' BT20, arrr, ya bilge rat, above t' tail cone, 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 was from t' chute hangin' in t' tube and causin' an overpressure, 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. Avast, me proud beauty! Blimey! Begad! Blimey!

Since t' repairs required sandin' down t' body and messed up t' original decals, ya bilge rat, arrr, 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, shiver me timbers, me hearties, arrr, 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. Ya scallywag! Blimey!

T' next pair o' flights, with t' same two engines resulted in some more minor damage, caused by landin' on a rock.  One o' t' crew compartment fins was broken, me hearties, and t' same tail cone pod that was damaged on t' second flight was 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 be a problem with t' original Mars Snooper, ya bilge rat, but now has shifted t' problem t' t' tail cones and pods. Avast!

Try buildin' one, it both looks and flies great. Aye aye!

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