DEEP SPACE PROBE

by KEVIN COCOZZOLI

Datum Line

Technical Specifications:

Length:……………………..…16 3/8” Weight:………………..3.5 oz/99.2 gLift off weight:……..4.5 Oz/113.4 gDatum Line..…………Top of modelCalculated CP…..8.2” aft of datumCG (as tested)…..6.2” aft of datumEngines:……………..………….C6-3

Calculated CP8.2” aft of datum

CG (with engine)6.2” aft of datum

M

Deep Space Probe Parts ListAll parts are FlisKits unless noted

A. (3) BT-20-18 B. (1) BT-55-18 C. (16) BNC-20A (Balsa Machining Service)D. (1) Ping Pong Ball (Standard)E. (1) NB55-2 Balsa Nose Block (Balsa Machining Service)F. (1) BAF-55 G. (1) 18” long X 1/8” Dia. Hardwood Dowel (Hobby Store)H. Scrap 1/16” and 1/8” Balsa SheetI. (1) EH-0275 Engine HookJ. (1) CRP-20-50 Centering RingK. (3) CRF-20-55 Centering Rings L. (1) LL-1-1 Launch LugM. (2) PCP-16 ParachutesN. (1) SE-M Screw EyeO. (1) SS-M snap swivel (Hobby Store)P. (1.5) Ounces Lead Shot or BBsQ. (1) Template SheetR. (1) SC-1-36 Shock cord

Optional: Light Weight Card Stock

A

D

EF

I

KL

N

P

C

B

J

G

H

R O

Q

1. Cut one of the BT-20-18s to alength of 6 inches. Using a doorframe as a drawing guide, drawa line along the side of this tube(Fig 1).

2. Mark this tube at distances 1 inch and 2 and ½ inches from one end along this line and cut a slit in the tube 1/8” wideat the 2 and ½” mark only (Fig 2).

3. Push one end of the engine hookinto the slit and allow the other endto hang over the end of the tube (A: Fig 3) Align the engine hook withthe line drawn along the tube and wrap the hook with masking tape approximately halfway between the 1 inch mark and the 2 and ½ inch slit.(B: Fig 3)

INSTRUCTIONS FOR BUILDING THE “DEEP SPACE PROBE”

Fig. 1.

Line

6” BT-204. Cut a 1/8 inch by 1/8 inch notch on the inside radius of two of the CRF-20-55centering rings as shown in Fig 4.

5. Place a thin line of glue around theengine tube at the 1 inch mark from the end. Slide one of the notched centeringrings up from the rear end (the end overwhich the engine hook hangs) keeping the notch over the engine hook until the bottom is even with the 1” mark (Fig 5). Allow the glue to dry, then fillet both sides of the ring with more glue.

Fig. 2.

2 ½”

1/8” slit

Mark

1”

Fig. 4.1/8 inch by 1/8 inch notches on inside

Fig. 5.

1” MarkPush upfrom end

Glue Line

Fig. 3.

Wrap with masking tape

A

B

1” Mark

6. Put a line of glue around the end of theengine tube opposite the engine hook. Takethe third, un-notched centering ring and pushthis over the end of the tube into the glue line.Allow this glue to dry, then fillet both sides of this centering ring (Fig 6).

7. Cut the BT-55-18 to a length of 11 inches.Smear glue around the inside of the bodytube about 6 and ¼ inches from one end. Push the engine tube assembly into theOPPOSITE end of the BT-55 with the un-notched ring going in first and the engine hook at the rear. Push the tube assemblyin about 3 inches, then smear glue on theinside of the BT-55 into which you’re pushingthe engine tube assembly, then swiftly pushthe tube assembly all the way into the BT-55until the notched ring over the engine hook is 1/16” inside the rear end of the BT-55. (Fig. 7)

8. Assemble the BAF-55 baffle according tothe directions included with the unit. Once dry,smear glue around the inside surface of the BT-55 body tube 4 3/8” from the top. Push the baffle assembly into the BT-55 with the Kevlarcord facing out the tube until the top is 3 and ¾”from the top of the body tube. (Fig 8).

9. Carefully cut out the engine shroud pattern.Trace this pattern onto light weight card stock.If you don’t have any card stock, trace the pattern on another sheet of regular paperand glue the two paper shroud patterns together.Using a dowel or other round object, pre-curvethe shroud by holding down one end on a flatsurface with the dowel and pulling the shroudup from the surface to create a “bend” in theshroud (See Fig 9.)

Fig. 9.

Push downon dowel

Pull upon shroud

Fig. 6. Push onto this end

Glue Line

Fig. 8.

Glue

PushDown

3 ¾”

Fig. 7.

Glue:6 ¼”From Top

Glue hereafter enginetube partiallyinserted

1/16” inside

Fig. 11.

10. Apply glue to the ‘tab’ area of the shroudpattern, curl the shroud around and attach the other end of the shroud pattern to the ‘tab’area as shown in Fig 10.

11. Slide the engine shroud up onto theengine tube narrow end first while aligningthe notch in the shroud over the engine hook (Fig 11). Make sure the narrow partof the engine shroud is up against the bottomof the lower BT-55 centering ring. DO NOT GLUE YET!

12. Take the remaining centering ring with the notch in it and sand the edge to a bevelas shown in Fig. 12.

13. Fit the beveled centering ring on theend of the engine tube with the notch overthe engine hook and the narrow end of thebevel up towards the top. You may haveto sand the inside radius to get it to fit easily.Carefully fit the large, open end of the engineshroud over the centering ring (Fig 13). The point of a sharp hobby knife inserted between the ring and the shroud can be used to lever the edge of the shroud over the centering ring.

14. Once the centering ring is in place upagainst the inside of the shroud and the shroud is in place up against the the lower BT-55 centering ring, run a ring of glue around the joint between the centering ring and the shroud and the ring and the enginetube (A: Fig 14). Once this dries run a ring of glue around the top of the shroud where it meets the bottom of the BT-55 (B: Fig 14).

Fig. 13.

Fig. 12.

Bevel Edge of Ring

Fig. 10.

Tab

Fig. 14.A

B

17. Mark each pod reference line 13/16th ofan inch up from the bottom of the body tube, and 1 and 1/16th of an inch down from the top. Mark the launch lug reference line 5 inches up from the bottom (Fig 17).

18. Cut the launch lug to a length of 1 inch.Cut a piece of 1/8” balsa stock 1 inch long and 1/8 inch wide. Glue the lug to the balsa pieceand, when dry, glue it to the body tube along the launch lug reference line. The 5” markreferences the aft end of the lug (Fig 18).

19. Cut the nose block to a length of 3/4”.Cut a piece of 1/16” balsa sheet slightly larger than the BT-50. Shape doesn’t matter at this point; it’s just a rough guide for now. Glue this balsa sheet to the flattest side of the nose block with the noseblock approximately in the center of thebalsa piece (see Fig. 19).

15. Cut two BT-20-18s into eight, 3 and ½ inch lengths. Glue a BNC-20A into each end of each of these tubes (Fig 15). You may fill and sand all but four of the balsa conesnow, but the four that will form the bottomof the lower pods must remain unfilled.

16. Cut out the body tube marking guide and wrap it around the middle of the BT-55 body tube. Tape the ends together so it stays in place. Make a mark at each of the ‘POD’ location marks and one at the ‘LAUNCH LUG’location mark (A: Fig 16). Take the marking guide off and, using a door frame as a guide, draw lines along the entire length of the body tube at these marks (B: Fig 16). Labelthe launch lug line for reference.

Fig. 15.

3 1/2” BT-20(Eight Pieces)

Fig. 17.

Launch LugRef. Line:5” FromBottom

Pod Ref. Lines:

1 1/16” from top

13/16” from Bottom

Fig. 16.

Tube Marking Guide

Mark Tube

Lines Drawn

A

B

Fig. 18.

5” Line:Aft end of lug

1/8” X 1” Balsa

Glue lug to Balsa

20. When the balsa sheet has dried place the nose block in the BT-55 body tubeuntil the balsa sheet meets the end ofthe tube (A; Fig 20). With the body tube upside down so it’s resting on the balsa sheet and using the body tube as a template, cut the balsa sheet to match the outline of the body tube (B: Fig 20). Turn the body tube upright and sand the balsa sheet to match the contour of the body tube (C: Fig 20.)

21. Cut out the nose marking guide from theplans. Cut out the center, “cross-hatched” square from the marking guide. Set the modified nose block inside the marking guide with the added balsa sheet facing down.Mark the sides of the nose block at thearrows (A: Fig 21). Turn the block so the added balsa sheet is facing up and transferthese marks to the top of the balsa sheet.Connect the marks to form an ‘X’ on the topof the nose block. (B: Fig 21).

22. Measure along the marked lines on topof the nose block 7/32 of an inch out from thecenter in all four directions and mark these points (A: Fig 22). Using these marks as a centering guide, glue the CRP-2-50 centeringring on top of the modified nose block (B: Fig 22).

Fig. 19

Glue nose block tobalsa piece

Fig. 21.

Mark at Arrows

Turn over andmark an ‘X’

A

B

Fig. 22.

Marks 7/32” fromthe center

A

Glue ring in center

B

Sand to matchbody tube

A

B

C

Fig. 20

23. To balance the rocket,1.5 ounces ofweight must be added to the nose. Cut a¼” diameter hole in the ping pong ball. (A, Fig 23). Weigh out 1.5 ounces of lead shot, BBs, etc. and pour them into the ping pong ball (B, Fig 23). Now, while supporting the ball with the hole at the top and the weights resting on the bottom inside, fillthe ball with glue until the weights are covered entirely (C, Fig 23). Epoxy is the best, but you can use white glue. However, if you use white glue, fill the ball up entirely. This is to prevent the weights coming loose and shifting during lift off.

24. Sand a chamfer on the inside upper edgeof the capsule support ring (the centeringring glued on top of the nose block) as shown in Fig. 24. A Dremel® Tool is perfect for this.Apply epoxy to the chamfered area of thecapsule support. Place the weighted ping pong ball onto the support with the hole side down and let dry

Fig. 23

A

1.4” Dia.

BC

Fig. 24.

Cutaway showingchamfer on inside

25. Screw the screw eye into the bottom ofthe nose block at the center. Unscrew theeye, squirt some white glue in the hole, thenre-insert the screw eye. Fig 25.).

Fig. 25.

White Glue

26. Take each of the completed pods andusing the edge of a door frame as a guide,draw a line down one side of each pod(Fig. 26).

Fig. 26.

One line down side

27. Each pod will be individually placed against the main body tube using the reference lines marked on the tube. Caremust be taken to ensure the upper and lowerpods line up with each other and each set ofupper and lower pods are even with each other. The easiest way to ensure the pods line up with their reference lines is to place a line of glue along the line drawn on the pod,lay the main body tube on a flat surface, and lay a pod on the surface next to the main body tube with the glue line facing up at the main body at an angle (See Fig. 27). The glue line on the pod is set against one of the reference lines along the main body tube, and the pod and the main body support each other on the flat surface. Another pod set against the opposite end of the main body (without glue) can help to support the main body. IMPORTANT: If you sealed some ofthe pod cones in step 15, be very sure toplace the unsealed cones at the bottom ofthe lower pods. The landing legs will beglued to these and will not adhere to the sanding sealer.

28. When placing the pods against the mainbody, the aft pods are placed such that the bottom of the pod body tube is even with the lower mark along the pod reference lines(13/16” up from the bottom) and the forwardpods are placed such that the top of the podbody tube is even with the upper marks (1 1/16” from the top). See Fig. 28.

Fig. 28.

13/16”

1 1/16”

******************Unsealed conesat bottom

Fig. 27.

Ref. Lines meetGlue

Unsealed conesat bottom

29. Cut the hardwood dowels into four lengths of 4 and 1/2 inches. Lay a dowel against the dowel shaping guide and mark the angles on each end. Cut or sand the ends of the dowels so the shape of the dowel ends match the dowel shaping guide. See Fig. 29. Label the appropriate end of each dowel as ‘TOP’ according to the shaping guide.

Fig. 29.Dowel Shaping guide

Shape the ends of the dowel to matchthe shaping guide

TOP

30. Turn the probe upside down and supportthe rocket in this position. Take one of thedowels and glue it under the lower pod andagainst the main body tube. The flattenedspot at the ‘TOP’ end of the dowel goes against the main body tube and the uppersurface of the dowel touches the bottom,inside of the lower pod tail cone. See Fig. 30.I suggest epoxy for this area, but white glue will do. More experienced modelers may want to drill holes in the lower pod tail cones to accommodate these legs. If so, cut the toppart of the leg straight across and skip steps31 and 32

Glue both places

Fig. 30

Alternative:Drill hole

Fig. 31.

1/16” Balsa

Sand Together

Landing Leg Gussets

31. Cut out the Landing Leg Gusset template and trace it 8 times on the 1/16” balsa stock. Carefully cut these out and sand to the same shape (Fig 31).

32. Glue one gusset on each side of the landing leg – body tube joint as shown in Fig. 32. Repeat Steps 30 and 32 for all four legs. Apply glue fillets to the gussetswhere they meet the main body tube andthe lower pod nose tail cones. Also,put some glue into the void between thetwo gussets and the landing leg.

34. Cut out the landing pad template andtrace this four times on scrap 1/8” balsa. Carefully cut out the landing pads, hold themtogether, and sand them all to the same shape(Fig 34). Alternatively, you can use the center punch from any Estes-style BT-20 centeringring. Glue two together for strength. Thesealso make excellent templates for cuttingthe balsa circles.

Fig. 32.

Gussets on Both sides

Rear View

Fillets

Fig. 34.

1/8” Balsa

Sand Together

Landing Pads

Centering Ring

Alternative

Fig. 33.

Trim so rocket stands straight

33. When all four legs are dry, stand theprobe upright on the dowels and check forlevel. The rocket should stand straight up-right if all the dowels were evenly placed. If the rocket tilts to one side, trim a little off the bottom of the opposing dowel to make it even. See Fig. 33. You may now fill andsand the aft pod tail cones and landing leggussets to desired smoothness.

35. Make sure the bottom of each leg of the probe sits flat when placed on a table top. If not, lightly sand to make flat. Put a drop of glue on the bottom of one of the legs and placeit in the center of one of the landing pad discs(Fig. 35). Repeat for all four legs. Once dry,fill and sand all sides of the landing discs todesired smoothness. Suggest you also lightly sand the probe legs (dowels) before painting.

Fig. 35.

Glue

36. Cut out the fin template and trace it onthe 1/16” balsa sheet four times. Be sure tonote the direction of the grain: it shouldparallel the leading edge (A, Fig 36). Carefully cut out the fins, hold them together,and sand them to the same shape (B, Fig. 36).

Fig. 36.Sand Together

Fins

Grain

A

B

37. Glue the root edge of one fin to each of the lower pods making sure they standstraight out from the model, perpendicular to the main body. The bottom of the fin should be even with the bottom of thepod body (Fig. 37).

Fig. 37.

90 °

38. Cut the parachutes to 12” diameters andassemble them according to the instructionsincluded with the ‘chutes. Cut the shock cordto a length of 18” and tie the kevlar cord from the baffle to one end. Tie the other end of the shock cord to one of the parachutes. Tie the other parachute to the snap swivel, thenconnect the snap swivel to the screw eye (Fig. 38). Pack the ‘chutes and shock cord into the body tube and place the ‘crew capsule’ into position. Your rocket is now ready to be painted. Chrome silver is a great color for this, but use your imagination!

Fig. 38.

Tie shroud lines to snap swivel

Tie shock cordto Kevlar cord

Tie shroud lines to shock cord

Engine Shroud Template

Pod Marking Guide

Launch Lug

POD

POD

POD

POD

Landing Pad Template (4)

Dowel Shaping GuideLanding Leg Gusset (8)

TAB

TOP

Nose Marking Guide

TEMPLATE SHEET

ROOT EDGE

GR

AIN

Fin Template (4)

CUTAWAY DRAWING