MiniacRC Mighty Mini P-51B, Build Manual

Page 1: ... Materials and Tools 2 Warnings and Tips 3 Wings 4 Fuselage Fuselage Internals 11 Fuselage Molding 19 Hatch 28 Scoop 35 Empennage 37 Final Assembly 41 Finishing Touches Removable Wing Setup 43 Wing Fairings 45 Exhaust Stacks 47 Fixed Landing Gear 48 Electronics 50 ...

Page 2: ...ber band Popsicle sticks Structural Reinforcements Cardboard thin sheets of wood Landing gear 1 5 to 2 mm diameter music wire 1 75 in diameter wheels x2 Recommended Electronics Propeller 6 inch diameter 3 to 5 inch pitch two to three blade Motor brushless 2204 to 2205 stator size 2300 to 2450 kv Electronic speed controller 20 to 30 amp as rated for the motor Battery Lithium polymer LiPo 3S 800 to ...

Page 3: ...onger edge Build tips This build requires keen attention to detail but shouldn t contain any surprises for the seasoned hobbyist who has built FliteTest style models that involve molding Here are some tips Perform dry fits at each step before using glue Check for symmetry alignment and proper angles when dry fitting Take your time when pre molding the skins Reinforce appropriate bamboo skewer hole...

Page 4: ...oard wing skins spars ribs structural reinforcements and popsicle stick Remove paper on the indicated areas Bring the trailing edge of one side of the wing to the edge of the build surface Perform a deep edge bevel on the exposed foam ...

Page 5: ... later steps Perform deep double bevels on the leading edges of the wing and inboard skins The bevels should be about 3 8 in wide or roughly the width of 2 DTFB dollar tree foamboard sheets Tab and glue the front and rear spars onto the wing Trim the rear spars over the servo cavities ...

Page 6: ...ns of the wing Draw a line connecting the endpoints of the aileron cuts and another line marking where the end of the skin touches down when molded over Avoid these two lines when placing glue Placing glue on the spars the ribs and the leading and trailing edges mold each wing skin over ...

Page 7: ... to the exposed leading edges of the main wing Glue down the paper bleed over on the underside Widen the cuts on the spars so that a popsicle stick can slide through for the removable wing Mold each inboard skin over adding glue on all mating edges and trim the trailing edges flush ...

Page 8: ...the gap with extra foamboard or a Popsicle stick before applying glue Deeply bevel the indicated inside edges that will meet the bottom surface of the fuselage If you wish to have a removable wing glue the pictured reinforcement plate where the front spars meet Pass the Popsicle stick halves through the front and rear spars ...

Page 9: ...lf hang over the table Cut out the aileron hinge and provide some relief on the ends to ensure free motion Repeat this process for the other wing half Lightly etch the bottom of each aileron roughly 1 DTFB sheet s width from the hinge and remove the paper Bevel sand the exposed foam ...

Page 10: ...ure to scrape off any excess glue and check for free aileron motion Tape over the seams between the inboard and outboard skins for inverted g strength Add any paint prior to this and cover the tape with strategic decorations such as invasion stripes The wing of your p 51 is now complete ...

Page 11: ...powerpod using A folds The pod for this Mustang has 2 5 degrees of rightward thrust angle and 1 degree of downward angle Glue on the firewall and secure it with packing tape Glue together the nose box with B folds Attach the flaps under the nose box with the leftmost piece on the plans being placed at the front side Each flap should sit as far forward as possible leaving enough space for the forme...

Page 12: ...g that it lies parallel with the top surface The powerpod should fit snugly into the nose box Glue former A to the front of the nose box B and C into the grooves above and D through F underneath ordered from front to back Each former should be pressed all the way in ...

Page 13: ...x where the nose mold will attach Glue the other tabs on the right side with the long one placed rearmost Glue one side of the fuselage box onto the nose box Place glue forward of the line marked by the diagonal score cut on the doubler Press the pieces together between your hands ...

Page 14: ...e box Crack open the score cut to ensure that the rear flap of the fuselage is not glue down Perform a B fold on the center flap of the fuselage box and glue the free side of the fuselage box onto the receiver plate and the nose box Check for perpendicularity and symmetry ...

Page 15: ...uch that the its tab presses into the corresponding slot on the fuselage mold as shown on the left below Secure the chosen side of the rear fuselage to the receiver plate placing glue on the plate and in the cracked open score cut Dry fit the other side to ensure symmetry as the glue hardens ...

Page 16: ... For structural strength glue down the two flaps on top of the fuselage box Attach formers O and R underneath the fuselage as pictured Grab the vertical stabilizer plate and perform a standard 45 degree bevel cut on the rudder You may choose to reinforce the hinge with some glue Remember to scrape off any excess glue ...

Page 17: ...rward with glue Glue formers M and N on top of the fuselage box checking that each forms a 90 degree angle with the top surface Cut out the rectangular cavities on each side of the fuselage box Place a servo on each cavity and cut relief holes to allow the wings of the servo to pass through ...

Page 18: ...MiniacRC 18 Trim the nose box to be flush with the top of the fuselage box to allow the hatch to sit down properly in later steps The internal structure of your Mustang s fuselage is now fully built ...

Page 19: ... MOLDING Parts fuselage skin nose skin cowling Remove paper and or foam where indicated on the plans On the fuselage skin lightly bevel sand the front edges of all the protruding flaps to allow them to mold properly later ...

Page 20: ...er and a table rather than your fingers to firmly perform 180 degree mold overs with no wrinkling Crack open the score cuts separating the front and rear sides of the fuselage skin Dry fit the left side of the skin onto the internals making sure that all tabs press fully into their slots ...

Page 21: ...d fit the right side of the skin Bevel sand former M if necessary Mold the forward most bottom flap on one side of the fuselage skin and over the two former F s leaving half of the front former exposed Mold down the other side and place masking tape to hold the fit We ll now proceed to perform dry fits for the rest of the bottom flaps ...

Page 22: ...is unsatisfactory Place masking tape to temporarily hold the flap down Once you are happy with the fit of the Mustang s fuselage skin gently peel off all the pieces of masking tape leaving each of them wherever convenient for reuse in the same spot Repeat the above steps this time with glue To avoid placing glue in the wrong spots use a pencil to mark the desired glue location s as you work throug...

Page 23: ...in and bevel the rear edges of each flap except for the rear most flaps The sharper the curve the deeper the bevel should be Pre mold each flap well before proceeding to the next step Dry fit the flat middle part of the skin onto the left side of the fuselage checking the fit of tabs and slots ...

Page 24: ...he steps taken for the fuselage skin However trimming the formers will be much more important here Use a blade or a sanding block to bevel the front edge of each former that prevents a flap from molding over fully and sitting down properly Remove paper on the formers to ease trimming ...

Page 25: ...aps sanding wherever necessary Hold them down with masking tape Do the same with the two flaps up top Remove the tape and repeat the process with glue pre planning glue locations at each step Make sure to hold down each piece firmly to avoid leaving gaps with hardened glue ...

Page 26: ...ormer A Grab the cowling remove paper and bevel its rear edge Gently mold the cowling until the edges of each band meet Hold the fits with masking tape Place the cowl around former A and check that it aligns well with the front the nose skin ...

Page 27: ...does not accurately follow the outline of former A mold the cowling into a tighter radius where necessary with your fingers If the problems persist the best option is to remove the masking tape and begin by gluing the top of the cowling to the top of former A Work your way around the loop gluing only a little bit at a time Otherwise once you are happy with the dry fit remove the tape glue the edge...

Page 28: ...90 degrees with respect to the plate Glue the flaps at the ends of the plate using B folds and as the glue hardens perform a dry fit on the fuselage Adjust any angles as necessary The fit should be moderately snug You will see a small gap between each former and the left and right edges of the plate Using a blunt object lightly indent the top of each edge uniformly till this gap disappears This wi...

Page 29: ...ce as per the plans Otherwise determining the proper orientation may be difficult in later steps Mold each hatch skin Use a ruler and your build table to establish a tight molding radius near the edges of each skin rather than using your fingers and risking the possibility of wrinkles ...

Page 30: ...that side of the skin down scraping off excess glue Following the same steps glue the other side of the skin down Repeat this process for hatch skins B and C with C sitting flush with the rearmost flap on the hatch plate The forward edge of skin C and the rear edge of former K may require some sanding beveling Once all the skins are in place turn the hatch over and trim off only the excess foam Do...

Page 31: ...g a rocking motion the tight fit should loosen with repeated use Perform 45 degree bevels on the indicated edges of the windshield and former I It may help to reinforce the windshield with some posterboard on the outside Glue the canopy stringer under former I and glue them both to former J on top of hatch skin A as shown below ...

Page 32: ...hatch skin A checking for symmetrical placement Pre mold the posterboard canopy The canopy should wrap around the windshield and former I and meet hatch skin A on both sides Trim sand as needed till the fit is satisfactory and secure the canopy with masking tape ...

Page 33: ...e on former I the windshield and the outside edge of the canopy Hold the canopy down and scrape off excess glue Re apply the masking tape on that side making sure that it stays put Repeat the same process on the other side Once the glue has hardened remove the tape and trim off any excess posterboard foamboard where necessary As a final step glue together the two sides of the hatch lock and glue i...

Page 34: ... flight Look through the bottom of the fuselage as you pass the skewer for the first time to avoid tearing through the small hatch lock You may reinforce the hatch lock with cardboard or wood to sustain repeated use Use the circular brace to page C1 of the plans You are well on your way to completing the construction of the fuselage ...

Page 35: ...nal step of constructing the fuselage is to add the signature scoop Remove paper where marked on the plans and pre mold the scoop Glue on the stringer and the former on top of it Mold each side of the scoop over the top of the former and glue it down on the stringer ...

Page 36: ...oles on the scoop former and former O These will provide some degree of ventilation and reduce pressure drag Finally glue the scoop onto the fuselage as pictured checking for alignment as the glue hardens Let us now complete the fuselage by addressing the tail region ...

Page 37: ...e the hinges with some hot glue Scrape off any excess glue We will now bind the motion of the split elevators Bend a 90 degree angle into the end of the wire so that it sits down in the longer score cut provided on the right elevator Complete the U bend to whatever length you see fit as shown in the pictures above Perform a score cut where this torque rod falls on the opposite elevator ...

Page 38: ...e pressing it down with a sharp object The elevators should now be bound in their motion Glue the middle flap shut as shown above making sure that the elevators still have free motion Provide some relief for the elevators by running a wire through the indicated edges ...

Page 39: ...tured Follow up with a sander and form curves by focusing the rubbing motion near the middle of the bevels The curved cavities will allow the horizontal stabilizer to sit cleanly on the fuselage Sand additionally if needed Once satisfied with the fit glue the stabilizer to the fuselage ...

Page 40: ... hardens look at the fuselage from different perspectives to ensure that the tail surfaces are sitting at proper angles perpendicular to each other and aligned with the fuselage Reinforce the vertical stabilizer with additional glue on the mating edges The fuselage of your Mighty Mini Mustang is finally complete ...

Page 41: ...iling edge meets the side walls of the fuselage Check that the centerline of the wing and the seam inside the scoop align with each other Push the front of the wing up against curved belly of the fuselage There is bound to be a slight offset as shown above on the right We will close this gap by sanding a curve into the inside surface of wing similar to what was done for the horizontal stabilizer ...

Page 42: ...e shape of the fuselage belly Continue sanding with a curving motion till the fit of the wing is satisfactory Note If you wish to glue the wing in permanently skip to the Electronics section and install the wing servos first You are now ready to add the finishing touches of the assembly ...

Page 43: ...his subsection The removable wing option is desirable for storage portability and mild damage protection during botched landings Glue the two reinforcement braces to the inside walls of the fuselage using the slots for alignment The bamboo skewer should sit all the way down in the slots and rest on the braces Slide both layers of the rubber band underneath the Popsicle sticks on the wing ...

Page 44: ... the skewer up stretching the bands and lay it down inside the slots To make removing and reinstalling the wing less of a hassle tape the rubber band to the skewer vinyl electrical tape was used here Also glue the rubber band lock under the Popsicle sticks The wing should fit firmly against the fuselage now ...

Page 45: ... mates properly against the fuselage If the wing is to be removable apply masking tape on the wing as shown below to avoid gluing the fairings to the wing Tightly secure the wing with the rubber band Perform dry fits of both fairings The rear corner of each fairing should align with the trailing edge of the wing The fairings may need to be molded slightly near the front to meet the curved surface ...

Page 46: ...iece at first and then come back a second time to push the sharp tip into the seam between the wing and fuselage In the case of the removable wing apply glue only on the side of the fairing that will meet the fuselage When the wing is removed the fairing should still sit tight With that the signature fairings of the Mustang should be all set ...

Page 47: ...on Using the sharp tip of a bamboo skewer pierce through each hole on the stacks into the foamboard Do this at a 45 degree swept back angle as pictured above Reserve the forward most hole for the skewer that will secure the swappable powerpod Repeat the same motion with the blunt end to widen each hole all the way through As you do this cut the skewer leaving about a quarter to 3 8 of an inch jutt...

Page 48: ...e that they are mirror images of each other Slide a wheel into each landing gear wire trim the wire and lock the wheel in perhaps with a little bead of glue Place one wire against the bottom surface of the wing using the two dots as reference The upper leg of the wire 1 50 in long should face toward the wingtip Using a blade perform two score cuts on the wing surface along the wire Firmly glue the...

Page 49: ... wheel leg on the side of each landing gear wire using the etched line on the leg for alignment Press the posterboard wheel legs all the way into the score cut for strength Once you are happy with the fit glue both wheels legs down Your Mustang is ready to roll ...

Page 50: ...fuselage Widen the slots string pushrods through them and hook each rod to a servo arm using z bends Glue the servos into the square cavities on the fuselage pressing the wings of the servos into the relief cuts that were previously made Perform dry fits of the control horns into the tail surfaces and perform z bends at the appropriate points on the pushrods Check for free linkage movement and glu...

Page 51: ...rvos into their respective cavities Complete both control linkages with pushrods and control horns Secure the motor to the firewall on the powerpod using two or four screws and slide the pod into the fuselage Using a pushrod poke through both sides of the fuselage independently passing through the sidewall of the powerpod each time Pass a skewer through the fuselage securing the pod Reinforce the ...