Sikorsky Sea KingFuselage Instruction Manual

Length: 54" Body nose to body tail.Width: 18.5” Body left to right.Height: 13” Body bottom to top.Weight: 12-14 lbs. With full load of 60-90 size

mechanics and Radio equipment

Designed and Developed in the USASept, 2002 All rights reserved.

SEA KING SPECIFICATIONS

Century Helicopter Products

Century has designed a new Sikorsky S-61 Sea King. Changes tofull-size helicopter designs are a direct challenge to the modeler. Toits predecessor, the Century model Sea King fuselage has many tinydetails to catch your eye, and major detail features make a tremen-dous difference to the overall impression.

CN4004 Sea King Scale Fuselage ManualWarningThe Sea King fuselage is designed to use Century’s flexible cable drive system, this requires that the mechanicsinstalled use a wire drive tail shaft or can be modified from a shaft or torque tube drive system. A belt driveA belt driveA belt driveA belt driveA belt drivesystem is not compatible.system is not compatible.system is not compatible.system is not compatible.system is not compatible. Consideration also must be taken when choosing a gyro as the demand from the cabledrive system will require a lower gain setting and the heading hold gyro is generally not recommended from thehigh stress imposed on the tail. A good rate gyro will work very well.

In order to use the Retract system included in this instruction, it is assumed that the mechanics to be installed isof the rear facing engine designrear facing engine designrear facing engine designrear facing engine designrear facing engine design.(all X-Cell 60,ST,CT & SE) If it is preferred to install a mechanics using aforward facing engine, then additional modifications will be necessary for the Retracts to operate.

It is worth while mentioning at this time that if the scale multi main and tail rotor systems will be used that it isbest to install the lowest gear ratio available for the chosen mechanics. Lowest referring to the engine to mainshaft gear ratio that turns the main rotor disk the slowest (usually the main gear has the largest number of teeth)to maximize engine torque to drive the 5 blade main rotor system. It is also important to understand that themain rotor RPM range should fall in the 900-1200 range due to the increased number of rotor blades on the mainhead and the tail rotor.

Congratulations on purchasing Century’s magnificent scale fuselage of the Sea King.Congratulations on purchasing Century’s magnificent scale fuselage of the Sea King.Congratulations on purchasing Century’s magnificent scale fuselage of the Sea King.Congratulations on purchasing Century’s magnificent scale fuselage of the Sea King.Congratulations on purchasing Century’s magnificent scale fuselage of the Sea King. The fuselage ismanufactured from lightweight fiberglass using Epoxy resin with carbon fiber filament reinforcement at seamsfor extra strength. The fuselage has a pre-primed surface and has the major open sections precut for conve-nience. All wooden parts are precut and labeled for easy identification. Semi-scale Retractable landing gear andwheels add that little extra that has made Century famous for their quality fiberglass scale fuselages.This instruction set is to aid the modeler in the construction of their fuselage, however, due to the large number ofhelicopter mechanics available on the market, this instruction will only detail the general case. In many instances,additional modifications will be necessary to adapt to your helicopter.

Fiberglass main body parts Pre-cut wood parts Clear windshield

Section One: Tail Drive & InstallationStep 1. Insert the flexible cable into the brass tubeStep 1. Insert the flexible cable into the brass tubeStep 1. Insert the flexible cable into the brass tubeStep 1. Insert the flexible cable into the brass tubeStep 1. Insert the flexible cable into the brass tubeInsert the flexible cable into the brass tube (to keep thebend smooth, without kinks) and tape off at one end.Slowly bend the long brass tube, make the bends gradualin intervals using your hands. Do not cut the length ofthe brass housing at this time, this will be done near thevery end of installing the flexible cable drive system. See Fg.1

Step 2. Locate F15 and F16Step 2. Locate F15 and F16Step 2. Locate F15 and F16Step 2. Locate F15 and F16Step 2. Locate F15 and F16Locate F15 and F16, these formers (photo #1) are for mounting the tail gearbox to the elevated tail section. TheF16 former will be glued to the F15 former with the offset notch to the front part of the F15 former. The basic

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design is to use the existing vertical fin mounts on the tail gearbox tosecure the tail gearbox to the wood former. Depending on the tailgearbox to be installed, additional mounting may need to be designed atthe top of the gearbox (this is at your discretion). Position and mark theholes for the vertical fin mount so the gearbox when bolted to the F16former is either flush against the F15 former or is flush to the insideedge of F16 former. Depending on the tail gearbox, additional shimsmay be required. Drill through the plywood F16 former and deburr theholes.

Step 3. Disassemble and examine the tail gearboxStep 3. Disassemble and examine the tail gearboxStep 3. Disassemble and examine the tail gearboxStep 3. Disassemble and examine the tail gearboxStep 3. Disassemble and examine the tail gearboxDisassemble and examine the tail gearbox, if possible install a grease fitting. This canbe as simple as a small hole drilled into the gearbox housing and a matching screw thatdoes not interfere with the internal workings of the gearbox or a brass tube Epoxiedflush to the inside surface with a cap commonly used to cap antenna tubes. If install-ing a Century scale model tail gearbox (part#CN1109, photo #2) continue with thelettered steps, for other tail gearboxes read and make modifications as necessary foryour tail gearbox. See Fg.3

Step 3a. Installing Century’s tail gearboxStep 3a. Installing Century’s tail gearboxStep 3a. Installing Century’s tail gearboxStep 3a. Installing Century’s tail gearboxStep 3a. Installing Century’s tail gearboxThe following instructions detail installing Century’s tail gearbox into the elevated tail section of the fuselage.The finished solution will have the left half (half without tail pitch bellcrank mount) of the tail gearbox installedpermanently with a removable top portion of the right tail gearbox half. This will allow complete disassembly formaintenance of the tail gears and the flexible cable drive shaft and couplers.

Step 3b. Examine the right gearboxStep 3b. Examine the right gearboxStep 3b. Examine the right gearboxStep 3b. Examine the right gearboxStep 3b. Examine the right gearboxExamine the right gearbox half (with the mount for the tail pitch lever mount), measure and mark on the outsidehousing the position where the outside plastic wall of the first ball bearing is located (30mm from the end of thegearbox). Using a razor saw (very thin saw blade) cut flush to this wall, completely through the right gearboxhalf. Now the tail gearbox is in three parts. Remove the lower right half (with the vertical fin mounts) this part isno longer used. Initially assemble the F16 and F15 formers (do not use glue at this step) and install the tail gear-box assembly onto the F16 former. Position and mark the location of the F15 former on the outside of the fuse-lage using pencil (some sanding and grinding of the inside surfaces of the tail section may be necessary). Markboth above and below the former and the angle as exactly as possible. This location is ideal when the three boltsthat fasten the tail gearbox assembly are all accessible and the tail output shaft is generally centered in the open-ing in the top of the tail section. Note, in order to get the correct angle as suggested in the full size plans for theflexible cable system some grinding of the right gearbox half at the rear is necessary alongwith a small section of the bottom edge of the opening in the elevated tail section.

Step 3c. Clean and degrease the left gearboxStep 3c. Clean and degrease the left gearboxStep 3c. Clean and degrease the left gearboxStep 3c. Clean and degrease the left gearboxStep 3c. Clean and degrease the left gearboxThoroughly clean and degrease the left gearbox half (with the lock nut recesses) with alco-hol. Using CA or Epoxy, bond three new lock nuts into the respective cavities, apply lightoil to the threads if necessary to keep the threads clear.

Step 3d. Measure and mark the tail gearboxStep 3d. Measure and mark the tail gearboxStep 3d. Measure and mark the tail gearboxStep 3d. Measure and mark the tail gearboxStep 3d. Measure and mark the tail gearboxMeasure and mark the tail gearbox input shaft so the shaft fully engages the series of set screws on the flexibledrive coupler and the stepped end is flush to the ball bearing. Using a cutoff wheel, remove the remainder of theshaft and grind two flat spots that are 90 degrees apart and correspond to the set-screw locations on the coupler.Using a countersink or a larger drill bit, enlarge the smaller exit hole slightly where the flexible cable will exit thecoupler. See Fg.2

Step 4. Gearbox other than Century’sStep 4. Gearbox other than Century’sStep 4. Gearbox other than Century’sStep 4. Gearbox other than Century’sStep 4. Gearbox other than Century’s

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If installing another tail gearbox other than Century’s, follow the example detailed above and make the requiredmodifications to mount into the tail section.

Step 5. Installing a flexible cable drive systemStep 5. Installing a flexible cable drive systemStep 5. Installing a flexible cable drive systemStep 5. Installing a flexible cable drive systemStep 5. Installing a flexible cable drive systemA key element in installing a flexible cable drive system (photo #3) is to make sure the ends of the brass housingare properly secured. It is our recommendation to buy some additional 1/8” plywood and cut two 7/8” diameterround circles. The F15 former has precut hole for the coupler to pass through, however in many installations thebare flexible cable will be exposed at this point (as when using the Century tail gearbox (part#CN1109). Bondboth wooden circles to each other and then bond below (make sure the former is positioned in the correct direc-tion) the F15 former using Epoxy. Mark the centerline of the tail gearboxinput shaft (simple when only one half of the gearbox is mounted to F16) anddrill straight through with a drill bit that is 1/16” larger than the brass hous-ing.

Step 6. Install the tail pitch leverStep 6. Install the tail pitch leverStep 6. Install the tail pitch leverStep 6. Install the tail pitch leverStep 6. Install the tail pitch leverInstall the tail pitch lever to the tail gearbox with the necessary steel ball andmark the location for the flexible rudder pushrod (included with the fuselage)to pass through the F15 former. Again, drill the hole 1/16” larger than thesize of the outside housing.

Step 7. Prepare to permanently bondStep 7. Prepare to permanently bondStep 7. Prepare to permanently bondStep 7. Prepare to permanently bondStep 7. Prepare to permanently bondTo prepare to permanently bond the F15 former into the elevated tail section, several things need to be com-pleted. The brass housing, the rudder pushrod, and the left tail gearbox half need to be installed. First decide thebest method to bond in the former. The recommended choices are:- Drill several small holes in the fiberglass body along the centerline of the former, once the former is moved

into final position, inject Stabilit or Epoxy using a syringe inserted into each hole, while forcing the fiberglassslightly away from the wood former. As the syringe is remove the fiberglass compresses against the woodformer forcing any excess glue to the edges. Repeat process for all holes.

- Using a saw or moto-tool grind vertical slots in the edge of the former spaced 1/8 ” apart. Measure and markthe inside wall where the final position of the top surface of the former will be. Once ready, use a Q-tip orapplicator and apply Stabilit or Epoxy above the mark on the inside of the fiberglass and to the outside edgeof the former. Wipe any excess from the edge leaving adhesive inside the slots. Move the assembly into finalposition, as the former passes through the glue previously applied to the inside of the tail section it will form asolid bond to the former.

- A variation on the first approach is to grind a slot through the centerline of the former 1/16-3/32” deep anddrill only a few holes through the fiberglass. As the adhesive in injected, it will flow around the former andbond it in place.

Step 8. Test fitted into the inside of the tail sectionStep 8. Test fitted into the inside of the tail sectionStep 8. Test fitted into the inside of the tail sectionStep 8. Test fitted into the inside of the tail sectionStep 8. Test fitted into the inside of the tail sectionThe F15 former needs to be test fitted into the inside of the tail section. Inspect the internal opening and grind orsand any excess material that will interfere with test fitting the former. To make this task simpler, tie a cordthrough the pushrod and drive shaft hole to make removing the former simple. Sand the edges until the formercan be moved into the final position with your fingers without excessive force. Once satisfied, stop here.

Step 9. Before the F15 former is permanently bondedStep 9. Before the F15 former is permanently bondedStep 9. Before the F15 former is permanently bondedStep 9. Before the F15 former is permanently bondedStep 9. Before the F15 former is permanently bondedBefore the F15 former is permanently bonded in place the same work needs to be performed on the remainingformers (F14, F13 & F12) that will position the brass housing. At this point skip down to Step 23d and completethis step as it uses the F12 former as a template. Inspect and grind or sand any material that will interfere withinstalling these formers. Also verify that the holes match the brass housing, make any changes at this time. Eachformer needs to be prepared and test fitted according to your preferred gluing method. However, access to theseformers is from the front, so that at least one side of each former can be properly reinforced by filleting. Againstop here without gluing the formers in place.

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Step 10. To prepare to mount the tail wireStep 10. To prepare to mount the tail wireStep 10. To prepare to mount the tail wireStep 10. To prepare to mount the tail wireStep 10. To prepare to mount the tail wireTo prepare to mount the tail wire strut for the tail wheel, match the wire strut to the plans and make a mark onthe fuselage where the strut will exit the fuselage. It is best to position the wire strut so the bottom surface of thestrut rests slightly above the floor of the fuselage. It is important to make this slot taller than necessary to allowthe wire to flex or deflect when landing. A wooden block needs to be prepared to mount the wire, using 1/8”plywood (not included) cut a 1/2” wide strip 2” long. Measure 3/8” from one end and mark and drill a 1/8” holestraight through. Mark a line from the hole to the end furthest from the hole. Cut a 1/8” slot along this line toreceive the wire strut, remember to test fit the strut to make sure the wire fits flush into the plywood block. Testfit the length of the block with the wire strut into the fuselage, some sanding or grinding may be necessary to get agood fit. Trim the length of the wooden block if necessary. Using a sanding block, sand the bottom of the blockinto a “V” to match the bottom surface of the fuselage. Once satisfied, permanently glue the wooden block inplace using Epoxy capturing the wire tail strut.

Step 11.Step 11.Step 11.Step 11.Step 11.Compare, measure and mark the final position of the F14 former, corresponding to (F8) on the full size plans, on theoutside of the fuselage. Remember to do a final wipe down with acetone on the internal fiberglass section beforegluing, to clean and get the best bonding possible. Following the chosen gluing method, permanently bond the F14former in place.

Step 12.Step 12.Step 12.Step 12.Step 12.Although not detailed on the full size plans, the rudder pushrod needs to be supported along the tail section of thefuselage. Mark 2-3 additional locations similar to the brass housing formers for the pushrod on the full size planmatching the height of the rudder pushrod. Using 1/8” plywood (not included) cut out these formers to a heightof 1/4”-1/2” above the top of the pushrod from the plan. These need not be the full width of the inside of thefuselage but can be 1 1/4” wide using a triangular reinforcement to add stability when bonded in place. Markand drill the hole for the rudder pushrod. Stop here and decide the location of the rudder servo. Once this isfinalized, permanently bond the pushrod formers in place. Fillet one side of the former as they are glued intoposition.

Step 13.Step 13.Step 13.Step 13.Step 13.Carefully feed the brass housing through the F14 former, up and out through the opening in the top of the elevated tailsection. Do not bond the brass housing to F14 at this time. Similarly, feed the rudder pushrod through the supportformers and out the top.

Step 14.Step 14.Step 14.Step 14.Step 14.Before the end of the flexible cable can be used, the last 5/8-3/4” of the cable needs to be “tinned”. Silver Solder ishighly recommended but Rosin Core Solder can be substituted, heat the end of the cable with a soldering iron until thesolder takes to the cable. Continue until an even silver coating has been applied. If the end will no longer fit into thecoupler, gently file along the length of the end until it can be fully inserted into the coupler.

Step 15.Step 15.Step 15.Step 15.Step 15.With both the brass housing and the pushrod extended through the top opening in the elevated tail, test fit the tailcomponents one last time. Assemble the tail gearbox with the coupler and attach the prepared end of the cable. Slidethe end of the brass housing into the modified F15 former and insert the pushrod housing. Make the connection for theend of the rudder pushrod to the ball on the tail pitch lever. Inspect and verify that the end of the brass housing has agap of 3/16-1/4” before contacting the coupler, measure and write down the exact position, noting the amount if any,that the brass housing is protruding past the F15 former. Measure and write down the same information for the rudderpushrod housing, remember that the final position must allow complete end to end travel of the pitch plate assembly.

Step 16.Step 16.Step 16.Step 16.Step 16.Depending on the type of tail gearbox used, one may have to modify the order of the following instructions before

permanently bond the F15 and F16 former in place.

Step 16a.Step 16a.Step 16a.Step 16a.Step 16a.For the Century tail gearbox, bond the F16 former onto the F15 former. Place the formers (still referred to asF15) into the cavity and reposition. Bond the brass housing and the rudder pushrod housing in place using slowCA, or Epoxy using the information collected in Step 15. Attach the unassembled left gearbox half (w/o the tailbellcrank mount) to the F16 former using socket head bolts and lock nuts (not included).

Choice: 1. Cut the top off the fiberglass tail to install the gearbox assembly then reattach the top of the elevated tail.2. Use a heat gun to soften the top section, flex the opening to allow installation of the gearbox. Once thegearbox is inside, let the fiberglass cool to return to the original shape.

Step 16b.Step 16b.Step 16b.Step 16b.Step 16b.Once the left half of the gearbox is inside the top of the elevated tail, move the gearbox with the F15 former into thefinal position. This position corresponds with having direct access to all the hex bolts that secure the right gear-box half in place. Using the preferred method to bond formers, permanently glue the F15 former into the tailsection using Epoxy or Stabilit.

Step 16c.Step 16c.Step 16c.Step 16c.Step 16c.Slide the flexible cable out through the end of the brass housing and attach the cable to the tail coupler shaft (this canbe done outside) that is assembled onto the tail gearbox input shaft. Slide the shaft assembly into the tail and engagethe ball bearings while mating the tail output shaft. Grease the gearbox at this stage.

Step 16d.Step 16d.Step 16d.Step 16d.Step 16d.Re-attach the right gearbox side and tighten the three hex bolts. Check for smooth operation.

Step 17.Step 17.Step 17.Step 17.Step 17.If another tail gearbox assembly is being installed,If another tail gearbox assembly is being installed,If another tail gearbox assembly is being installed,If another tail gearbox assembly is being installed,If another tail gearbox assembly is being installed, read the previous step to become familiar with the process beforefinal positioning and permanently bonding the formers in place.

Step 18.Step 18.Step 18.Step 18.Step 18.Using a ruler, estimate the center of the tail output shaft and make pencil marks on the edge of the opening. Match thetail cap and transfer the marks. Using the ruler, mark the center of the shaft and drill or grind out a 1/4” diameter hole.Further enlarged to include clearance for the tail pitch lever and the tail pitch plate as required.

Step 19.Step 19.Step 19.Step 19.Step 19.Install the pitch plate assembly with the tail pitch lever. Re-attach the rudder pushrod ball link to the tail pitch lever.

Step 20.Step 20.Step 20.Step 20.Step 20.Before installing the F13 former (coresponding to F7 on the full size plans), glue the brass housing to the F14 formerand the pushrod housing to it’s matching former. Also reinforce the former by forming a fillet of Epoxy around theedge of the former and the fiberglass wall. Permanently bond the F13 former in place and repeat the reinforcing.

Step 21.Step 21.Step 21.Step 21.Step 21.Take the time to reinforce the tail wire mount prepared in Step 10, using fiberglass cloth (not included) cut andbond a section of cloth over the plywood mount and extend 3/8-1/2” away from the mount. A good method toreduce the vibration of the brass housing is to fill expandable foam around the brass housing between the form-ers. This method has been proven to effectively dampen vibration. However, care must be taken to cleanly applythe foam and remember to have permanently bonded formers prior to this step.

Step 22.Step 22.Step 22.Step 22.Step 22.Insert and slide the F12 former (corresponding to the F6 former on the full size plans) into final position andpermanently bond in place using the chosen method. Remember to reinforce the edge with a fillet to the fiber-

glass. Note that the rudder servo no longer is required to be mounted directly behind the mechanics, the generalrule is to make the rudder pushrod as short as possible to reduce slop in the control surface. The exact servoposition is the modeler’s choice and is no longer detailed in these instructions. However, it can be easily mountedand finalized after completion of the wooden substructure in the next section.

Section Two: Wooden Substructure

Step 23. Step 23. Step 23. Step 23. Step 23. (photo#9)The Sea King fuselage has undergone substantial redesign in order tomake access to the main mechanics simple. To accomplish this there isa completely new wooden substructure that takes advantage of thelarge door cutout in the side of the fuselage to access the rear mechan-ics. This new substructure virtually slides into final position beforepermanently being bonded in place. At all remaining steps, refer tothese written instructions and disregard the formers labeled on the fullsize plans.

Step 23a.Step 23a.Step 23a.Step 23a.Step 23a.Insert the main retract mechanism into the rectangular hole (some enlarginglength-wise makes this simpler) in F4 while positioning the two F7 woodenblocks (photo #3) in between the main retract mechanism and the surface ofF4. Mark along the outside edge of the F7 wooden blocks and permanentlybond in place using Epoxy. Position the retract mechanism once again andmark and drill the four 3mm (1/8”) mounting holes and deburr after drilling.The four 3x16mm Socket Cap Screws with flat washers and lock nuts will beused to attach the retract mechanism after the substructure has been fuelproofed or painted. Position a servo into the upper slot and mark the screwholes for the servo. Remove the servo and drill four 1/16” holes.

Step 23b.Step 23b.Step 23b.Step 23b.Step 23b.NOTE:NOTE:NOTE:NOTE:NOTE: To make sure that your chosen mechanics will be supported insidethe fuselage, the F1 Floor former (photo #4) has the key tabs cut, but thetwo F3 rail formers have not had the notches cut from their bottom edgeto match. Once you have followed these instructions, and marked thelocation of your mechanics in the assembly, you will then mark and cutout the notches for these tabs.

Initially, attach the F11 and the F4 formers to the F3 Rail formers usingmasking tape. Slide this assembly into the main fuselage and align theholes for the retract axle. Slide the main section of the mechanics (withoutfront servo tray, tail boom assembly or main shaft assembly) and verify that the rearmost landing gear holes willfall inside the assembly (photo #5, next page)..... Make a pencil mark on the F3 Rail former for the center location ofthe rear landing gear hole. While installed also mark the center of the main shaft on the F3 Rail. Examine thecenterline height of the tail output shaft and compare to the F11 former, as a slot may need to be made in the F11& possibly the F9 former. Remove the mechanics and the wooden substructure.

Step 23c.Step 23c.Step 23c.Step 23c.Step 23c.Position the two F3 Rail formers with the straight edge on the bottom and key the F4 former into the angled slots.Do not use glue at this stage. Turn the assembly over near the edge of the table and lay the F1 Floor former overthe bottom of the F3 Rail formers. Position the F1 floor former such that the rear landing gear bolt marked onF3 in step 23b falls 1/2" from the back of F1. If not, reposition the F1 former to allow for this. If this is not anissue, simply allow a 1/4” gap between the rearmost edge of F4 and the front of F1. Mark the appropriate loca-tion of the front and rear tabs of F1 onto the bottom edge of the F3 Rail formers. Using a razor saw and chisel or

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a jig saw, cut out these marked slots in the bottom of the F3 rail formers suchthat the bottom of F1 fits flush with the bottom of the F3 rail edge. It is best to cutand fit one end at a time to get the best fit. Some sanding may be necessary.

Step 23d.Step 23d.Step 23d.Step 23d.Step 23d.Using the F12 former, match to the top of the F11 former and transfer the slotlocation (made previously) by tracing the inside edge of the slot. Repeat for the F9former. It may not be necessary to cut the slot into the F9 former as it depends onthe actual centerline height of the tail output shaft on the helicopter mechanicsbeing installed.

Step 23e.Step 23e.Step 23e.Step 23e.Step 23e.At this stage permanently bond the F4 former (photo #6) to the F3 Rail formersusing Epoxy. Once dry bond the F1 Floor former in place and reinforce the insidejoint by either filleting or using two lengths of balsa or spruce triangle stock (notincluded) to increase the strength. Verify during the curing time that the substructure dries true (the F1 Floorformer is 90 degrees to both the F3 formers). Attach the front F5former and the rear F11 former. Let these completely dry. Finallyattach the F9 and F10 formers (make sure that each former dries at90 degree relationships to one another. Let the substructure cureovernight.

Step 23f.Step 23f.Step 23f.Step 23f.Step 23f.Mark a centerline down one side of both F2 hardwood rails. Mark aslight taper on the side edge using a ruler of both the F2 rails anduse a sanding block, add the taper. It is important that both railshave the same amount of taper. This will naturally angle the rotordisk down in the front, building in some natural forward cyclic.Once again slide this completed assembly into the main fuselage andalign the holes for the Retract axle. At this point inspect the front and rear fit of the former to the fuselage, somesanding may be required to get a good fit at the seam of the fuselage down the center and at the sides. Oncesatisfied with the fit slide the main section of the mechanics (without tail boom assembly or main shaft) andposition the two F2 hardwood landing gear rails underneath the mechanics (with the taper) towards the front.Align the main shaft centered in the opening and position both F2 rails to have the landing gear bolt holes alignedover the centerline (drawn in pencil if necessary) on the top mounting surface of the F2 rails. Using the pencil,mark the position of the F2 rails on the F1 Floor former and the exact position of the landing gear holes on the F2hardwood rails.

Step 23g.Step 23g.Step 23g.Step 23g.Step 23g.Remove the substructure and permanently bond both F2 hardwood rails in place using Epoxy. After curing,drill the four landing gear holes matching the size of bolts (for your mechanics) and deburr the holes. Repositionthe mechanics and mark the location of the exit holes for the cooling fan exhaust inside the F2 rails. Drill thecorners and remove the unwanted material. It is recommended to finalize the mounting location of a RemoteGlow Plug Adapter and a Fueling Valve at this time as access is very simple now. The large door on the right sideof the fuselage will facilitate this but requires some ingenuity to fashion the door to easily open and close withoutdamage, while having a robust mounting to handle the vibration of the helicopter during operation. Reinstall thesubstructure and transfer the cooling hole to the fiberglass floor using pencil or marker. Again, it is best to drillthe corners and use a moto-tool to make the straight cuts with a Cut-off wheel, then only final sanding of thefiberglass is required.

Step 23h.Step 23h.Step 23h.Step 23h.Step 23h.

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The substructure needs to be fuel proofed before it is permanently installed into the fuselage, using a fuel proofpaint that matches your color scheme, paint all wood surfaces. Alternately, mixing rubbing alcohol with Epoxycan be used if you wish to preserve the nature wood look of the formers.

Step 23i.Step 23i.Step 23i.Step 23i.Step 23i.From Step 23a, install the retract mechanism and the servo intothe F4 former (photo #7), note that the pushrod from the servo tothe retract mechanism will be located below the F4 former.Hardware is not provided for this connection, but can be as-sembled similar to this example. Install two threaded steel ballswith hex nuts onto the Retract actuating pushrod and to theservo horn. Install the steel ball at a distance of 10mm from thecenter of the servo. Make up a pushrod that is 37-40mm fromcenter to center on the links. To install the pushrod, temporarilyconnect the retract servo to the aileron channel, with the radioturned on and the aileron trim centered. Push the servo armonto the servo with the ball at 90 degrees to the length of theservo. Adjust the length of the pushrod until the output leg (on top) of the retract mechanism is at maximumtravel of the mechanism, this is close to a 10 degree offset position from vertical. Remove the pre-installedpushrod and slide the axle into position with the pushrod mounting location on the right side. Attach the twoeasy connectors provided to the retract leg. Using threadlock on the steel hex nut, secure the leg on the axle sothat the plastic connectors are on the left side. Stop here, final adjustments will be made after the sponsons are inplace.

Section Three: Main Fuselage Preparation

Step 24.Step 24.Step 24.Step 24.Step 24.Start by thoroughly cleaning the main fiberglass fuselage, tail, tail fin, side door, dome, sponsons, top and frontsections with mild detergent and water. Let dry and wipe all fiberglass surfaces with acetone.

Step 25.Step 25.Step 25.Step 25.Step 25.Test fit the horizontal fin to the top of the elevated tail section, some sanding may be necessary to get a perfect fit withthe fin overlapping the boss on the fuselage. Using Stabilit or Epoxy bond the horizontal fin in place using tape to keepthe fin square to the tail (90 degrees). Once completely dry, using additional Stabilit or Epoxy (mixed with Mi-cro-balloons), fill the seam to blend the horizontal fin to the tail section.

Step 26.Step 26.Step 26.Step 26.Step 26.The two sponsons that house the retractable landing gear require preparation before painting. Using a large marker,coat the entire surface of the boss on the sponson that will be bonded to the side of the fuselage. Make a print of theairfoil shaped surface, on thick paper or card stock . Mark the left and right sponson letters on the back of each tem-plate. To make this a functional template, use a compass or a circle template and draw a second circle on the outside ofthe axle hole that has a 3mm (1/8”) larger radius. This will be obvious when you trim the template to be an exact matchto the sponson. Cut both the inside axle hole and the outside edge. Continue to cut from the paper and trim until youhave an exact match to the airfoil section. Starting on the right side of the fuselage, as detailed in the full size plans,draw a pencil line that extends along the bottom of the small rectangular window (just forward of the axle hole on thefuselage side) to just past the trailing edge of the paper template (as mounted over the hole for the retract axle). Re-move the axle pushrod and slide the axle in place through the fiberglass main section and center using tape to secure theaxle from the inside. Slide the templates onto the axle. Starting with the right side, match the template angle to the fullsize plan. Once satisfied, hold the template in place with tape. Measure from the leading and trailing edge of thetemplate to the pencil line and transfer these measurements to the left side of the fuselage. This will match the angle ofthe sponson boss. Now tape the left template in place.

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Step 27.The sponson templates created are exact matches to the boss on the sponson. Using a pencil or a fine marker,trace the template onto the fuselage. Remove the template and the axle. Carefully sand or scrape through thegelcoat surface to the bare fiberglass, staying 1/8" inside the guideline. (As we have added to the template tomake it functional, only remove material that is inside the airfoil shape). Use the template to fine-tune the fit.Locate and rough cut the vacuum formed upper strut mount..... To prepare for gluing later, compare to the de-tailed area on the side of the fuselage and mark with a pencil. Repeat the same procedure to remove the insidegelcoat surface where the part will be bonded to the fuselage (this may only be a thin line around the outside edgeof the clear part). Also find the shaped fiberglass strut, this needs to be cut in half and then trimmed to fit.

Step 28.Using white glue or similar non-permanent adhesive, temporarily attach both sponsons and upper strut mountsto the side of the fuselage in their final position and angle. Having cut the strut in half previously, start by cuttinga high angle to meet the fuselage and be flush to the inside of the vacuum-formed part. The strut is only for showand will not contribute any strength to the sponson but must be well attached to endure the vibration of thehelicopter. The bottom end of the strut is to be shaped to meet the sponson. Once satisfied with the position,mark and scrape the gelcoat surface where the strut meets the sponson. It is worth the effort at this time to per-manently mount the top of the strut to the clear plastic mount and to blend the surfaces to form a single compo-nent. This will alleviate tedious work when the strut is attached to the fuselage. After painting this will be as-sembled.

Step 29.Step 29.Step 29.Step 29.Step 29.Once all the sponson preparation is completed, remove all pencil and marker lines with rubbing alcohol, followedby acetone. Once dry. Tape over the areas that have had the gelcoat surfaces removed and cut away the extramaterial using a hobby knife. This will allow painting without disturbing the bonding surface.

Step 30.Step 30.Step 30.Step 30.Step 30.There are 24 pieces of 3/8” square plywood screw mounts and 24 M3x8 self tapping screws. These are to attachthe front fuselage section, the top hatch and the tail cover to the main fuselage body. There is no set rule forusing all of these pieces to attach the hatches. Start by taping the front fuselage section and the top hatch to themain fuselage using masking tape. Using a ruler, mark lines that are 3 to 4 inches apart, that overlap both thefront sectionand main fuselage, and the top hatch and the main fuselage. At each of these marks, measuring 1/8”in from the edge of the hatch, mark and drill through the hatch and the main fuselage using a 3/32” drill bit.Once all the holes are made, remove the mating parts and roughen the surface on the inside at each drilled holelocation using sandpaper. One at a time, bond the 3/8” plywood squares centered over each hole from the insideusing slow CA or Epoxy. Let completely dry and drill though the wood using the 3/32” drill bit. Using one selftapping screw, form the threads in all the plywood blocks. Finally, apply one drop of the fast CA glue to eachhole to harden the wood.

Repeat this process to mount the tail cap to the elevated tail section.

Step 31. (photo#10)Step 31. (photo#10)Step 31. (photo#10)Step 31. (photo#10)Step 31. (photo#10)Carefully inspect the windshield and the cheek windows, there is a fine trim line on each clear window. The wind-shield section that is included in the fuselage may fit into the front section without separating the different windows, ifthis course is followed it is imperative that an exact method of bonding the windshield in place is religiously followed.Using a marker, follow the trim line to improve the visibility. For extra precaution, draw a second line 1/4” on theoutside of the first line and trim each part. This preliminary step allows test fitting of the slightly oversized window tosee exactly how much additional trimming is necessary. In some instances, the clear part can be bonded in place aswithout further trimming. Once each part is test fitted, use rubbing alcohol to remove any residual marker from theclear part. Stop here until after the fuselage has been painted to install the clear parts.

Final installation of clear parts:

Once the fuselage is painted, clean and wipe acetone (do not get any on the painted surface) on the inside surfaceof the window openings on the fuselage to be bonded. Using “Goop” or “R/C 56 windshield adhesive” commonlyfound in the local model-airplane hobby shop, apply an even coat to the edge of the windshield. Be careful not toBe careful not toBe careful not toBe careful not toBe careful not toget any adhesive or acetone get any adhesive or acetone get any adhesive or acetone get any adhesive or acetone get any adhesive or acetone on any area of the clear part that will be exposed as a window, as they may create ablemish that cannot be removed.

Step 32.Step 32.Step 32.Step 32.Step 32.Installation of the side doors can be done in the closed or open position. In either position, the doors are bondedto the main fuselage using Epoxy. Remember to install after painting and prepare the contact edges by sandingthrough the paint before permanently bonding in place.

Step 33.Step 33.Step 33.Step 33.Step 33.Position the wooden substructure and place the helicopter mechanics into the center section of the fuselage with themuffler fitted to the engine. Measure, mark and drill/grind the hole for a flexible exhaust diverter (not included) toevacuate the exhaust from the fuselage. Do not attempt to route the exhaust to the “scale” positions as the extra lengthof the exhaust diverter will cause unpredictable and inconsistent engine performance that is highly undesirable in ascale helicopter.

Step 34.Step 34.Step 34.Step 34.Step 34.The next major task is to attach the tail section to the main fuselage section. This can be done after the fuselage ispainted but it is recommended to complete before to allow filling and blending of the tail to the main fuselage. Start bysanding through the gelcoat surface of the mating surface on the main fuselage section and sand the inside sur-face of the tail section. Test fit the joint to make sure the two parts match correctly when brought together. Alsonote that the brass housing and the flexible cable drive system need to be routed through the F11 and F9 formersin the process of bonding the tail section. Do not bond the brass housing in place until after the tail drive systemis completely connected and working. Once satisfied, mix up plenty of Stabilit or Epoxy and coat one surfacewith glue and slide the two parts together. A little preparation here can go a long way, sight the front to backalignment and look at the side view for proper alignment, blocks of various sizes can be used to hold the tailsection until cured. Secure both the main fuselage and the tail assembly in place using long strips of maskingtape. Make adjustments as necessary to get the perfect alignment.

Step 35.Step 35.Step 35.Step 35.Step 35.Insert the tail coupler onto the tail transmission output shaft on the mechanics. Mark and grind the appropriate flatspots positioned at 90 degrees to one another on the tail shaft. Also remove any extra shaft length using the moto-tool with a cutoff wheel. Remember to deburr the end of the tail shaft when finished and to slightly countersinkthe entrance hole where the flexible cable will enter the coupler.

Step 36.Step 36.Step 36.Step 36.Step 36.Install and align the main helicopter mechanics into the main fuselage to center the main shaft with the top hatch of thefuselage. Move the mechanics off to the in order to complete the measurements required for fitment of the t/r drivewire. Initially position the brass housing flush against the side of the mechanics. While viewing from above, mark onthe brass housing the position that will be approximately 1/2”past the end of the tail coupling already installed on thetail output shaft. Trim the brass housing at the marked location and deburr the end.

WarningIt is recommended, once the cut point has been decided, to disassemble the tail gearbox assembly and remove theflexible cable. NOTE: cutting the brass housing with the cable inside will almost guarantee a burr on the inside ofNOTE: cutting the brass housing with the cable inside will almost guarantee a burr on the inside ofNOTE: cutting the brass housing with the cable inside will almost guarantee a burr on the inside ofNOTE: cutting the brass housing with the cable inside will almost guarantee a burr on the inside ofNOTE: cutting the brass housing with the cable inside will almost guarantee a burr on the inside ofthe housing. This will result in a tail drive failure shortly after lift off on the maiden flight.the housing. This will result in a tail drive failure shortly after lift off on the maiden flight.the housing. This will result in a tail drive failure shortly after lift off on the maiden flight.the housing. This will result in a tail drive failure shortly after lift off on the maiden flight.the housing. This will result in a tail drive failure shortly after lift off on the maiden flight.

Step 37.Step 37.Step 37.Step 37.Step 37.Slide the flexible cable drive shaft into final position but do not completely re-assemble the tail gearbox. Measureand mark where the flexible cable would be positioned inside the tail coupling at the front. Again, remove the

mechanics. Trim the flexible cable using the cutoff wheel on the moto-tool. Do not try to use side cutters to cutDo not try to use side cutters to cutDo not try to use side cutters to cutDo not try to use side cutters to cutDo not try to use side cutters to cutthe cable as you will damage the cable. the cable as you will damage the cable. the cable as you will damage the cable. the cable as you will damage the cable. the cable as you will damage the cable. Once trimmed, the last 5/8-3/4” of the cable needs to be “tinned”. SilverSolder is highly recommended but Rosin Core Solder can be substituted, heat the end of the cable with a solder-ing iron until the solder takes to the cable. Continue until an even silver coating has been applied. If the end willno longer fit into the coupler, gently file along the length of the end until it can be fully inserted into the coupler.

NOTE:It is important at this stage to lubricate the entire length of the cable inside of the brass housing with a thick, hightemperature grease. Our best recommendation is to use a product designed for lubricating the same types of flexibledrive shafts in R/C model boats. Installation usually consists of squeezing an amount of grease into the tail end ofthe housing and inserting the flexible shaft completely until grease exits the front end of the housing. The cablecan be coated ahead of time.

Step 38.Step 38.Step 38.Step 38.Step 38.Included in the kit are two “L” channel brackets. These are to brace the mechanics to the F11 or F9 formers. Ashelicopter mechanics have evolved over the last decade, there may or may not be a vertical surface to attach the bracketto the mechanic, in this case some fabrication is necessary to make the connection. Align the “L” brackets andmark and drill the mounting locations. Using socket head cap screws and lock nuts (not included) mount the “L”bracket to both the mechanics and the closest former. After final installation of the mechanics and the flexiblecable has been attached, then the “L” brackets can be attached.

Step 39.Step 39.Step 39.Step 39.Step 39.To prepare the dome, depending on the version of the SeaKing that is being built, remove the gelcoat surfacefrom the rounded keys. The dome is to be mounted on the tail section just past the joint between the tail and themain mechanics. Once located, mark and sand through the gelcoat surface for bonding after the fuselage hasbeen painted.

Step 40Step 40Step 40Step 40Step 40The choice to permanently bond the wooden substructure in place really comes down to how much masking willbe done to avoid having over-spray coat the substructure, this may be an issue if it has been painted a differentcolor to the outside fuselage. Having test fit the substructure on repeated occasions you should be an expert forinstalling it. In a similar fashion to bonding the tail formers, this will be done with the same technique. Issue thatneed to be considered is the exact alignment of the Retract axle holes, preparing the inside fuselage surfaces for aproper bond at the locations where the formers that contact the floor of the fuselage have been marked. Roughsanding of the fiberglass contact areas. Once dry, reinforcement is recommended, a minimum filleting of theformers to the fuselage or additional reinforcing with fiberglass cloth (not included) and Epoxy resin.

Section Four: Final assembly

Step 41.Step 41.Step 41.Step 41.Step 41.Once painting is completed these steps will assist in assembling the working mechanics. Insert the flexible cable andclean the end of shaft that will engage the tail coupler with acetone, let dry and secure two 4x4mm set screws usingthreadlock. Attach the “L” Brackets to secure the rear of the mechanics to the fuselage.

Step 42.Step 42.Step 42.Step 42.Step 42.Using the hardware provide with the helicopter kit, secure the main mechanics at the landing gear points. Due to thelimited clearance, two solutions can be used to gain access to the lock nuts underneath the F1 Floor former. Onesolution is to cut 3/8” holes directly aligned with the lock nut positions and a Nut Driver can be used to tighten thebolts. Alternately, access can be gained thought the cooling fan hole in the bottom of the fuselage, however completeaccess is tedious.

Step 43.Step 43.Step 43.Step 43.Step 43.

Having removed the pushrod mount from the Retract axle, insert the axle,making sure the pushrod hole aligns with the retract mechanism. Once theaxle is past the F3 Rail former (photo #8), slide two F8 Round formersbefore the axle exits the other side. The axle pushrod can be reassembledand we recommend that threadlock is used to secure the lock nut for extrasecurity. Using a ruler, match the distances from the fuselage wall to theend of each side of the axle, this will ensure that the landing gear legs arecentered in the sponsons. Once satisfied, using small clamps or tape, lockthe position of the axle from the outside of the fuselage. Next we need tosecure the axle from moving laterally (side to side) by bonding the F8Round formers to the axle without having the adhesive make a mess andrestrict axle rotational movement. The best method to do this is to apply asmall amount of lubricant to the side of F8 that will be sandwiched betweenthe F3 Rail former. This must be done with care to avoid hindering thebonding surfaces between the F8 and the axle. Once complete, slide the F8 former away from the F3 Rail formerand apply an even amount of Epoxy to the surface of the axle at a position of 1/8” before the surface of F3 Railformer. Slide the F8 former gently until it contacts the F3 Rail former. Fillet the outside joint with Epoxy, rein-forced with thin strips of fiberglass cloth (not included) for extra strength. Repeat for the other side. Leave todry completely.

Step 44.Step 44.Step 44.Step 44.Step 44.Attach the pushrod linkage to the Retract mechanism. Remove andthreadlock the set screws that hold the wheel axles (on the bottom of thealuminum mount, photo #9), do not threadlock the securing set screw thatwill control the angle at which the landing gear axle is positioned. Slideone 2” wheel onto each side of the landing gear axle followed by one 5/32”wheel collar and use threadlock on the securing set screws. The goal is tohave the wheel spin freely but without any lateral movement on the axle.Slide one 1 1/4” wheel onto the tail gear wire and secure with one 1/8”wheel collar using threadlock. Remove the Socket Head Cap Screw thatwill secure the wire landing gear onto the axle and position and tape thesponson in position and insert the completed landing gear assembly. Testthe position of the landing gear to ensure that as the retract mechanism isactuated, the gear will properly retract into the sponson. It is best to dothis testing with the radio turned on and the retract servo connected tem-porarily into the Aileron channel. Remember to set any ATV on the channel to maximum at the beginning andfine tune by reducing the end points until the desire travel is obtained. On satisfied with the settings, record andtransfer the ATV setting to the gear channel for final testing.

Step 45.Step 45.Step 45.Step 45.Step 45.Once completely satisfied with the operation of the retracts, place some tape or a make a small mark at the positionwhere the wire landing gear leg enters the axle. Disassemble, measure and mark the location for a flat spot at the topend of the wire landing gear. Make sure the flat spot is made at a close angle to have the wheels parallel to one another.Once painted and the sponsons are installed, attach the main landing gear struts using a hex key inserted into theopening in the sponson on the end of the axle. Any fine tuning of the angle can be done with the set screw locatedat the bottom of the assembly.

Section Five: Painting

This fuselage is molded using epoxy resin and a combination of glass cloth and glass strips. Fiberglass fuselages havealways been criticized as brittle, difficult to work with and difficult to repair. Todays modern epoxy resins haveproven all of these statements to be false. Their strength, compared to the space age canopies that are common on

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most pod and boom helicopters, there is no contest. This plastic material is virtually indestructible at the penaltyof being virtually un-paintable without specialized and expensive automotive primers and paints. Consequently,there is also a very limited range of colors available. The reason you are reading this page is that you want to flya model that looks and holds all the prestige of a real helicopter.

FlexibilityFlexibilityFlexibilityFlexibilityFlexibilityA wonderful attribute of fiberglass is in its flexibility. Century and Funkey are proud of the craftsmanship thatgoes into every fuselage. However, fiberglass parts may migrate while inside the shipping box. When two matingcomponents are brought together and they do may not align or mate perfectly. Dealing with this is very simpleusing the following simple procedure. Using a heat gun, set at the high setting, at a distance of 1-2 feet away,evenly heat the warped part until the outside surface is hot to the touch and the part has become pliable (flexible).Using adhesive tape, mate the two fiberglass parts together and let both parts sit until both parts have reachedroom temperature. Remove the tape and now both parts are stable and match one another. In some instances,depending on the location of the warp, the part may need to be held in an over-extended position to achieve theproper shape when the part is finished.

Dealing with Fiberglass.Dealing with Fiberglass.Dealing with Fiberglass.Dealing with Fiberglass.Dealing with Fiberglass.Fiberglass is easier to repair than you think. Using today’s CA type of adhesives, a severe crack in a fuselage canbe simply fixed and the repaired section is much stronger than in its original state. Add touchup paint and noone would ever know it had been damaged. There is a limit to the amount of work one may wish to do in orderto repair extensive crash damage. At this time one can simply use the option to purchase the replacement fiber-glass part.

The Paint Job.The Paint Job.The Paint Job.The Paint Job.The Paint Job.There is no magic to a good paint job, the true secret is time, patience and common sense. A modeler who thinksthat they can throw paint onto a fuselage Friday night before flying on Sunday is dreaming, the helicopter wouldbe flyable but even that is a stretch. The average modeler will spend the better part of a month to apply a goodclean paint job.

Preparing the fuselage for painting.Preparing the fuselage for painting.Preparing the fuselage for painting.Preparing the fuselage for painting.Preparing the fuselage for painting.After opening the fuselage, examine all the fiberglass components to see where work needs to be done to allow asimple “bring up” of the fuselage. “Bring up” describes the necessary steps to complete all the jobs in order tostart priming the fiberglass parts. Typical work that is done at this stage is rough sanding on seams and jointedcomponents, filling of surface imperfections, adding panel lines and rivets, cutting required holes and prepara-tion for priming.

Step 46.Step 46.Step 46.Step 46.Step 46.Start by thoroughly washing all fiberglass parts in mild detergent and water, this will remove any residue re-maining from the molding process. Next wipe down all the parts with Acetone (from the hardware store). TheAcetone will remove all traces of oil or grease that will affect the adhesion of two fiberglass parts or between thepaint and the fiberglass. Now using steel wool or an abrasive pad commonly used for scrubbing dishes, scuff allsurfaces that will be joined or receiving paint. What is important to note here is that we are breaking through thetopmost resin surface and creating the best surface for the adhesive or primer. The prepared finish will havevery fine score marks usually seen when the part is held to the light at a slight angle.Step 47.Step 47.Step 47.Step 47.Step 47.This is the time to rough sand any accessories or small parts, using the 320 grit sandpaper, that will be assembledand attached at different positions on the fuselage. These can be marking lights, engine exhausts, scale fuel tanks,horizontal and vertical stabilizers, guns, antenna or any scale details being bonded to the fuselage. These accesso-ries should be test assembled to make sure that all parts are prepared, and you will be able to see any problemsthat may arise in trying to paint these parts. Some thought should be put into how to hold the part as it is beingpainted. Go ahead and bond these parts at this time using slow CA glue.NOTENOTENOTENOTENOTE: As the fuselage resin is epoxy, regular 5-30 minute epoxies can be used to bond two fiberglass compo-

nents together or any other item to it - wood or metal to the fiberglass.

Step 48.Step 48.Step 48.Step 48.Step 48.Once the detail parts have been built into the sub assemblies are ready to paint, use a filler in sections that havegaps or slight surface imperfections, occasionally there are voids (air bubbles in the resin) that occur near thesurface that need to be filled. There are allot of good fiberglass fillers on the market, it is best to check with yourlocal hobby shop to get a recommended product. Try to stay away from porous fillers designed for wood as theywill shrink and are not a good choice for larger areas.

Step 49.Step 49.Step 49.Step 49.Step 49.Most major windows and accessory holes have been precut by Century, leaving only those that have a user dependencylike the type of exhaust system used on the helicopter or the exact exit position for the cooling fan shroud.

Step 49a.Step 49a.Step 49a.Step 49a.Step 49a.When making cutouts or holes in the surface of the fiberglass the best procedure is to drill a pilot hole using the 1/16”drill bit at corners or along a curve. Start with using a permanent marker to draw the opening or window. The pilotholes serves to avoid leaving sharp corners which given the nature of a helicopter will be the focal point for stresscracking originating from the corner. Once the holes have been made, use the moto-tool for all other roughing cuts.The cut off wheel is the best for straight lines and either the sanding drum or the curved stone is used for smooth-ing edges. If the cut out is a window, do not use the moto-tool for the final work. Switch to a sanding blocks,square blocks of various sizes for straight edges and round dowels for rounded corners.

Step 49b.Step 49b.Step 49b.Step 49b.Step 49b.The exhaust opening should be 1/8” larger across the outside diameter of the exhaust pipe that extends below thebottom of the fuselage. After drawing the circle, use grinding stone and move in small circles until the hole is atthe size wanted.

Step 50.Step 50.Step 50.Step 50.Step 50.Priming the fuselage accomplishes two tasks: firstly, the primer paint is designed to aggressively adhere to thesurface being painted and provide the best surface for the colored paint to adhere to; secondly, all surface imper-fections will become visible. Depending on the particular imperfection, light sanding and the second priming willtake care of 90% of the highly visible problems. The remaining 10% need to be filled, let dry, sanded and thensprayed with the second coat of primer. The primer process will be repeated until the surface is as perfect asyour patience and time permit.

Step 51.Step 51.Step 51.Step 51.Step 51.Select your paint color and follow the directions on the particular brand of paint being used as each manufacturer hasdifferent requirements.

Step 52.Step 52.Step 52.Step 52.Step 52.Spray cans vs Airbrushed finishes. The preference is left the to the modeler, many good paint jobs have beenaccomplished using spray cans. However, a good spray can finish requires more attention than using anairbrush. If you want a professional looking fuselage that does not have the extra weight resulting from an overapplication of paint, airbrushing is the choice.

As for selecting the type of paint there are two different schools. For beginners, visit your local hobby shop andask their opinion on painting fiberglass. As a general note, polyurethane is always a very safe paint that is fuelproof. The key is the last point, a perfect paint job can be easily ruined by spilling raw 15-30% fuel accidentally.There is no paint manufacturer who will tell you that their product will resist 30% fuel for very long and for themost part the fuselage is only exposed to the oil residue from the burned exhaust. We all know very well that intight, restricted fuelling areas like those encountered in most scale helicopter, fuel spills will result from time totime.