Construction Article By: John Mitchell

Aero Protect Recommended Hardware Kit for Carden 40% Extra 260 and Extra 330 (click on PDF icon to the left)

This project actually started last year (2000) for me after losing my Carden 35% Extra 300S during an IMAC contest. My 40% Carden CAP 232 was now my primary plane (at this point my only plane) and it was time for a new addition to the hangar. I spoke with Dennis and asked what would be on the drawing board next. When I found out it was going to be a bigger Extra 300S (which evolved into the 330S) and I was given the opportunity to be a part during the prototyping stage I was ready. The great thing about this project is Dennis and Caroline from Carden Aircraft and Dave from Desert Aircraft are all just a phone call away and all patiently willing to go over details, questions, and concerns throughout the project. Now for the plane specifications for my Extra 330S:

• Carden 40% scale Extra 330S
• Wingspan: 118 inches
• Fuselage Length: 113 inches
• Wing Area: 2601 square inches
• Engine: Desert Aircraft DA150 twin cylinder gas with KS Tuned Pipe Exhaust System
• Smoke System: B&B
• Prop: Air Models 28 x 12 3-Blade Carbon (Desert Aircraft)
• Radio: JR10X with dual R950 receivers
• JR8411 digital servos on all control surfaces
• JR2721 on throttle
• Pilot: Virtual Reality 40% scale Patty Wagstaff (prototype planned for production)
• Covering: Monokote and lots of it !! – The plane will be done following Patty Wagstaffs Red Tail Paint scheme. I had the opportunity to take pictures and make detail drawings of the graphics of the plane while it was in her hangar. I am still smiling from that one.
• Graphics: Pro Scale Models (prototype planned for production)
• Paint: PPG Omni Base Coat Clear Coat System
• A very understanding family (especially wife – Michelle) and a big building area.
• For pictures of Pattys plane see her web site at www.pattywagstaff.com
• Construction started: January 26, 2001

For a complete list of parts used please visit the Hardware Kits Section.

The Wings

Wing1 My first step with the wing core is to cut the servo bays, servo support notches, and servo wire exit slot. I have made templates from lite ply and hot wire cutting tools from 12 gauge copper wire. I place wheel collars on the wires and use them to set the depth of cut. Using a soldering iron with the copper wires I first cut the servo supports slots then the servo bays. I then use a long straight edge and cut the servo wire exit slot. Accurate measurements are critical to make the servo bay cut outs after sheeting.

Wing2 Hot wire cutting complete.

Wing3 Servo mounts epoxied in place.

Wing4 Servo wire exit slots.

Wing5 Wing phenolic tube with balsa end cap in place and trial fit of the socket support plate.

Wing6 Wing tube socket support scribed to sand to shape.

Wing7 This tip comes from Bob’s Edge540 construction web page. I will be using Pro Bond to glue the phenolic tube into the cores. With a ¼ inch drill make a few small funnels in the top of the wing core along the hot wire groove. This makes it easier to get the Pro Bond down in the tube slot.

Wing8 I still choose to glue all the sheeting together. This makes large sheets that can then be cut to size. A lot of encyclopedias work well on a flat table to keep the sheeting flat while it dries.

Wing9 The big sheets being cut into wing panels. Invest in 3M stock before starting this project because you will be using a lot of masking tape.

Wing10 Place the phenolic tube into its slot up to the first funnel and squeeze Pro Bond down the funnel. Slide the phenolic in and out twisting it and working your way down the slot. Make sure the tube is well coated and finally fill the hot wire slot. Tape over the slot and tape the tube socket in place. Place the wings in their cradles and weight them down for the glue to cure.

Wing11 I prefer gluing the sheeting together first because it allows me to pre-sand both sides on a flat surface with a palm sander and long sanding bar.

Wing12 Sanding wing cores prior to sheeting. Notice the Pro Bond filling the hot-wire groove.

Wing13 Bottom of the wing panel ready for sheeting. Notice the servo bay support slots have been filled in with scarp foam pieces.

Wing15 Wing panel after sheeting and trimming.

Wing16 Wing panels with leading and trailing edges being glued and held in place with masking tape.

Wing17 Using a micro plane remove the majority of the excess leading and trailing edge balsa.

Wing19 When the plane brings the excess balsa down close to the surface lay on 3 to 4 layers of masking tape to protect the surface from gauges while sanding the rough shape. Remove the masking tape and use the sanding bar to bring the leading and trailing edges down to the wing skin surface.

Wing20 The wing with the servo bays cut-out, leading and trailing edges installed and trimmed but the leading edge not sanded to shape. The ailerons have been cut free and all edges have been trimmed out. The bevel on the leading edge of the aileron and trailing edge of the wing assembly have not been done.

Wing21 The wing tips installed and sanded to shape.

Wing22 A view of the wing root with the wing tube sanded flush.

Wing23 Top view of the wing panel.

Wing24 Another view of the top of the wing panel and aileron.

Wing25 The hinge centerlines have been marked and the hinge points located. The aileron has been taped against the wing panel for proper alignment of the hinge point locations on each half.

Wing26 Another picture of the wing with aileron taped in place.

Wing27 The hinge locations have been drilled and the aileron leading edge and wing trailing edge have been beveled and shaped.

Wing29 Wing tip with aileron installed showing the beveling of both surfaces.
The wings have been prepped and sanded for covering. The covering has been applied to both wing panels with graphics to follow.

Wing30 Bottom view of the wing covered with servo bays opened and aileron in place with hard points installed.

Wing31 View of the rocket city hard point installed on the ailerons. The same has been done on the elevator halves.

Wing32 The wings finally covered with the graphics and gold pin stripe that cannot be seen in the picture.

Wing33 The bottom of the wings with graphics.

The Fuselage

Fuse0 Another tip I learned from Bob’s Edge540 Construction web page. There are two vertical braces fore and two more aft of the wing tube section. This area is where the 3/8-inch plywood anti-rotation plates glue to the inside of the fuselage. You will notice there is a 3/16-inch gap between the brace and the 3/8-ply block on each side. Do not glue the anti rotation blocks in. I opted to glue the rear vertical brace and using the ply blocks as spacer’s glue in the fore vertical brace. This will give more support to the anti-rotation blocks.

Fuse1 The fore vertical brace glued in place using the braces as spacers.

Fuse3 The anti-rotation blocks removed. Do not glue them in at this time.

Fuse4 One side truss assembly complete. I placed the long straight edge along the bottom horizontal 3/8-inch piece for construction. It would have been better to place it along the top horizontal piece.

Fuse5 The fuse socket support being epoxied in place.

Fuse6 I placed the second truss assembly on top of the first, with wax paper separating them, and glued on the other fuse socket support for the wings. Use a square and the wing tube to make sure everything is aligned. Also at this time make sure you are making a left and a right half!

Fuse7 Both truss halves complete with sheeting applied.

Fuse8 Taping off and sanding of top hatch ¼ inch balsa plate.

Fuse9 Sanding down to the masking tape. Remove the tape and final sand the edge to shape.

Fuse10 Bottom Deck sheeted and trimmed.

Fuse11 Top Deck sheeted and trimmed.

Fuse13 Instrument panel and bottom deck extensions sheeted.

Fuse14 The motor box sides have small marks showing the location of the center points for cutting the 4-inch lightening holes. I choose to only cut the top lightening holes because I will be installing KS pipes with the DA150 motor.

Fuse15 The 4-inch hole saw on the drill press.

Fuse16 Getting ready to install the ½ inch square ash to support F1 and the landing gear plate.

Fuse17 The ½ square ash epoxied and clamped in place. The 3/8-inch square balsa will support the floor that will separate the exhaust heat from the inside if the plane.

Fuse18 The motor box being epoxied and clamped together. I placed 3/8-inch square balsa braces to support F2 and F3 while glued. It also gives added strength to the glue joint against the motor box.

Fuse19 Another view showing all the clamps.

Fuse20 Starting to cut the top and bottom 3/8-inch cross braces. From Steve’s 330 page I borrowed the tip to cut and sand the top and bottom pairs so that each pair is exactly the same size.

Fuse21 After drilling the landing gear plate the ply and hardwood are taped for an 8-32 screw.

Fuse22 The firewall (F1), after being glued in place with epoxy, is pre-drilled to allow for 12 8-32 sheet metal screws adding to the structural support for the 150cc motor.

Fuse23 As explained in the intro to my construction descriptions I am installing KS pipes on the DA150 for this plane. Looking over the Edge540 construction web page Bob Hudson has put together I have applied his method for having the air exit the pipe tunnel. Here I have installed a 1/32 inch plywood sheet with a nice tight radius to allow the air to exit smoothly.

Fuse24 Another view of the front of the motor box with part of the sub-floor installed to separate the pipes from the inside of the plane and create a tunnel for cooling air to flow through. The balsa filler has also been added under F1 and sanded to shape.

Fuse25 The truss sides have been joined to the motor box assembly and all cross and diagonal bracing has been added. I use standard builders triangles from Home Depot to help keep the structure square.

Fuse26 Another view of the assembly with the wing tube slid in place to verify the phenolic tube is square in the structure.

Fuse27 The rudder servo control assembly is added at this point when I can still get to the cross bracing underneath to add some additional supports. I have designed this assembly so each servo is connected to and drives the bell-crank assembly. Installation is easy just epoxy onto the current cross bracing and clamp down. After the epoxy cures additional cross bracing will be added. I am considering kiting and selling the plywood structure if builders are interested. I will be starting a web page with more details very soon. If you are interested or have questions let me know. The hardware is Nelson and Hangar 9 with JR8411 servos.

Fuse28 Another view of the assembly clamped in place.

Fuse29 A closer view of the bell-crank assembly.

Fuse30 Another view.

Fuse31 The fuselage has been turned upside down and additional 3/8 square balsa cross bracing has been added to make the structure rigid.

Fuse32 Another view of the additional bracing along with the antenna tubes installed.

Fuse33 I drew on the planes the bell-crank location and rudder attachment crossing the pull-pull lines on the way back. I wanted to allow the wires to cross but not rub against each other so I installed a thin carbon fiber tube at the cross point at the proper height. Should work well and was very simple to do, You can also see the servo wire tube installed.

Fuse35 Rudder servo control assembly with antenna tubes and the servo wire tube to the rear installed.

Fuse36 Setting the wing incidence using the long robart bar and digital level accurate to a 10th of a degree. As you can see 0.0 incidence. Support the fuselage so it reads 0.0 or level before setting the wings to 0.0.

Fuse37 Another view setting the wings incidence.

Fuse38 Before going too much further with the fuselage construction I wanted to get the DA150 motor mounted and the KS pipes setup. This picture shows the motor standoff dowels cut to size and temporarily installed for motor and exhaust fitting.

Fuse39 The pipes have been bolted on the motor and the cans installed for now just resting in place. From this setup I can work out the dimensions for making the canister mounts and the cutout required for the front of the motor box. I will be using the mounting method developed by Steve Johnston on his Carden Edge 540. More info to follow.

Fuse40 Closer picture of the cans inside the fuselage.

Fuse41 The picture shows how the canisters will exit behind the landing gear mount. Most of the area will eventually be covered over with ¼ inch balsa. The pipes have an offset because of the cylinder offset. You can also see the curved plywood that will form the air exit.

Fuse42 Picture showing the header pipes and teflon couplers.

Fuse43 Picture of the fuselage in the upright orientation. You can see the hatch area that is still uncovered as part of the air tunnel in the fuselage. This area will give access to remove the canister hold-downs if the exhaust system needs to be removed for any reason.

Fuse44 Close-up front view of the DA-150 and pipes.

Fuse45 Side view of the header pipes.

Fuse 46 Along with bolting the pipes on to the cylinders the canisters also need to be supported inside the air tunnel. Again borrowing some design from Steve Johnston’s Edge 540 construction information I made-up two mounts from ½ poplar that will be epoxied in place on the landing gear plate under the seam of the canisters. For a heat buffer silicon tubing will be cut in half and applied to the edge of the poplar holder.

Fuse47 “AeroTrend” number 1061 silicon coupler is used.

Fuse48 View of the canister mounts in place and the canisters resting in the saddles with the silicon buffer.

Fuse49 Another view of the canister mounts.

Fuse50 The bottom deck and front side extensions have been attached. The ¼ balsa cross sheeting with a cutout for the canister pipe exits has been put in place.

Fuse51 Front view of fuselage. The air tunnel has been coated with a thinned mixture of epoxy and denatured alcohol.

Fuse52 A top view of the bottom decks with a better view of the pipe exit hole.

Fuse53 The bottom plate for the motor box has been installed with a large cutout for the pipes and canisters to be installed and removed for maintenance. It is also the air entrance for the tunnel to help cool the canisters and pipes.

Fuse54 Following Bob Hudson’s Edge 540 construction I made the rear bottom deck extension into a hatch to have access to the servo wires and rudder pull-pull cable exits. ¼ inch dowel pins are used in the front with a recessed single socket head #6 screw in the rear.

Fuse55 Another view of the bottom hatch in place.

Fuse56 Close-up of rear mounting screw. I used ½ dowel with a 3/8-inch diameter recess for the washer, lock washer, and screw. In this shot the dowel has not been sanded flush to the surface of the hatch.

Fuse58 The fuselage is upside down and the view shows the pull-pull cable exit points.

Fuse59 View of turtle deck being glued and taped in place. The 3/8 square blocks were tack glued in place to half on the fuse to define an edge for the turtle deck to follow.

Fuse60 Another view of the turtle deck glued in place.

Fuse61 Front view of the turtle deck.

Fuse62 ¼ balsa cross grain glued in place for the vertical fin-mounting platform.

Fuse63 Side view of the fuselage taking shape.

Fuse64 Another view of the fuselage taking shape.

Fuse65 Fuselage again.

Fuse66 Front view of the top hatch and fuselage side rounding for a smooth transition.

Fuse67 Vertical fin being glued in position.

Fuse68 Rudder and fin in position. Notice the cutout for the Nelson rudder control arm.

Fuse69 Close-up of vertical fin in position and rear capping of the turtle deck. I use ¼ balsa to cap off the turtle deck because I place a padded tie-down strap over this area when hauling the plane in the trailer.

Fuse70 Instrument dash mount being put in place. Notice the hatch area in the cockpit that allows me to remove the Patty doll and also have access in the cockpit area after the canopy has been glued in place.

Fuse71 Cockpit area

Fuse72 Starting to mount the cowl. Notice the balsa spacers taped in place for an equal gap around the rear of the cowl.

Fuse73 Lower cowl being fitted.

Fuse74 Lower cowl in place with DA150 and pipes in place.

Fuse75 Another view of the lower cowl. Front air intake was also cut out. After talking to Dennis when the cowl is completed I will block the area with a screen with balsa backing painted flat black. The opening can cause too much airflow over the carb resulting in carb adjustment problems.

Fuse76 Top and bottom cowl pieces taped in place.

Fuse77 KS Canister tie-downs. Heavy Duty ½ wide cable tie-wraps cut to size with .06 aluminum simple l-brackets and back plate.

Fuse 78 Close-up of mounting ends for the tie-downs.

Fuse 79 Opposite side of mounting ends with #4 screws to hold it together.

Fuse 80 Inside fuselage mounting of canister hold-downs. Number 8 sheet metal screws into the hard ash and number 8 flat-head screws through the landing gear plate from the underside.

Fuse81 Canisters and pipes assembled

Fuse82 Smoke tubing attached to the header pipe.

Fuse83 Pipes and canisters installed. Breather tube attached to the carb and the smoke tubing attached to the “T” fitting. The overflow / vent for the smoke and gas tank are visible with silicon protective sleeves attached to protect them from the heat of the canisters.

Fuse84 Another view of the smoke lines going into the pipes.

Fuse85 Number 8 screw up through the landing gear plate to lock-down the canisters.

Fuse86 Top view of the access area for the canister mounts.

Fuse87 Another view of the rudder control assembly with the pull-pull cables attached.

Fuse88 Rudder view of the pull-pull cable attachment.

Fuse89 Top view into the motor box – on the right is the smoke servo, smoke valve, and throttle servo. On the left is the B&B smoke pump.

Fuse90 Another view of the front end and looking back a little more to see the 50oz gas tank and the 40oz smoke tank standing on its side. Everything fits perfect just remember to setup your vent tube on the smoke tank for this orientation.

Fuse91 Another angle of the front-end.

Fuse92 Mounting of the two receivers.

The Elevator

Elev0 Using a builder’s angle to transfer the hinge line to the foam core.

Elev1 I have found there is no substitute for drawing the control linkage on the planes with measurements so when it comes time cut out the servo bays in the sheeting no mistakes are made.

Elev2 Servo supports glued in and taken to the root for added strength.

Elev 3 Another view

Elev4 The horizontal stabilizer cores have been sheeted using Pro-Bond glue.

Elev5 The sheeted cores have had the leading and trailing edges trimmed.

Elev6 The horizontal stabilizer halves with balsa leading and trailing edges installed. I use Elmers Outdoor wood glue and several tape strips to hold everything in place. The rudder is being done at the same

Elev7 The next step with the horizontal stabilizers is to get them ready for mounting on the fuselage and setting the incidence to zero. Here the forward mounting bracket hard-point is being readied for installation.

Elev8 The backside of the hard-point has a blind-nut installed and two wood dowels to help anchor it into the foam.

Elev9 The parting lines need to be drawn on the surface for the elevators.

Elev10 Here the stabilizers root and tips are being installed. I prefer installing them now and cutting the elevators free afterward. By doing it in this order the leading and trailing edges that will be installed will run the full length which makes it easy to bevel with the micro-plan.

Elev11 The elevators are installed on the fuselage and the incidence set.

Elev12 The incidence must be set at 0.0 degrees.

Elev13 I tack glue a small piece of balsa in place setting the incidence at 0.0. This makes it easy to install the L-bracket on the front of the stabilizer to hold the incidence.

Elev14 Front L-bracket in place. I recessed it into the balsa side against the hardwood mount in the fuselage.

Elev15 Elevators in place on the fuselage.

Elev16 Along with the L-bracket in front the stabilizer tube is also held in place with a screw through the tube and a hard-point. A ½ diameter hole needs to be cut through to the tube. I used a brass tube to cleanly make the cut.

Elev17 The hard-point for the tube is a ½ diameter dowel with a blind-nut on the side to go against the tube and I counter-bore the other side so the socket head screw is recessed.

Elev18 The underside of the stabilizer with the L-bracket installed and the tube screw hard-point in place. It still needs to be sanded flush to the surface.

The Rudder

Rud0 Foam core for the rudder after having the balsa sheeting glued using Pro-Bond. All edges have been trimmed.

Rud1 The rudder has been marked for parting from the fin.

Rud2 The rudder and fin have been cut and are ready for the leading and trailing edges to be installed.

Rud3 Vertical fin glued in place.

Rud4 Nelson hardware installed in the rudder and covering completed.

Rud5 Picture of the tail of the plane

Rud6 Close-up of the rudder counter balance with the checkerboard and gold pin stripe complete.

KS Pipe Installation with a DA150 Motor

Fuse14 The motor box sides have small marks showing the location of the center points for cutting the 4-inch lightening holes. I choose to only cut the top lightening holes because I will be installing KS pipes with the DA150 motor.

Fuse15 The 4-inch hole saw on the drill press.

Fuse16 Getting ready to install the ½ inch square ash to support F1 and the landing gear plate.

Fuse17 The ½ square ash epoxied and clamped in place. The 3/8-inch square balsa will support the floor that will separate the exhaust heat from the inside if the plane. The support floor is at the same level as the lower truss sides.

Fuse19 Another view showing all the clamps.

Fuse23 As explained in the intro to my construction descriptions I am installing KS pipes on the DA150 for this plane. Looking over the Edge540 construction web page Bob Hudson has put together I have applied his method for having the air exit the pipe tunnel. Here I have installed a 1/32 inch plywood sheet with a nice tight radius to allow the air to exit smoothly.

Fuse24 Another view of the front of the motor box with part of the sub-floor installed to separate the pipes from the inside of the plane and create a tunnel for cooling air to flow through. The balsa filler has also been added under F1 and sanded to shape.

Fuse38 Before going too much further with the fuselage construction I wanted to get the DA150 motor mounted and the KS pipes setup. This picture shows the motor standoff dowels cut to size and temporarily installed for motor and exhaust fitting.

Fuse39 The pipes have been bolted on the motor and the cans installed for now just resting in place. From this setup I can work out the dimensions for making the canister mounts and the cutout required for the front of the motor box. I will be using the mounting method developed by Steve Johnston on his Carden Edge 540. More info to follow.

Fuse40 Closer picture of the cans inside the fuselage.

Fuse41 The picture shows how the canisters will exit behind the landing gear mount. Most of the area will eventually be covered over with ¼ inch balsa. The pipes have an offset because of the cylinder offset. You can also see the curved plywood that will form the air exit.

Fuse42 Picture showing the header pipes and teflon couplers.

Fuse43 Picture of the fuselage in the upright orientation. You can see the hatch area that is still uncovered as part of the air tunnel in the fuselage. This area will give access to remove the canister hold-downs if the exhaust system needs to be removed for any reason.

Fuse44 Close-up front view of the DA-150 and pipes.

Fuse45 Side view of the header pipes.

Fuse46 Along with bolting the pipes on to the cylinders the canisters also need to be supported inside the air tunnel. Again borrowing some design from Steve Johnston’s Edge 540 construction information I made-up two mounts from ½ poplar that will be epoxied in place on the landing gear plate under the seam of the canisters. For a heat buffer silicon tubing will be cut in half and applied to the edge of the poplar holder.

Fuse47 “AeroTrend” number 1061 silicon coupler is used.

Fuse48 View of the canister mounts in place and the canisters resting in the saddles with the silicon buffer.

Fuse49 Another view of the canister mounts.

Fuse50 The bottom deck and front side extensions have been attached. The ¼ balsa cross sheeting with a cutout for the canister pipe exits has been put in place.

Fuse52 A top view of the bottom decks with a better view of the pipe exit hole.

Fuse53 The bottom plate for the motor box has been installed with a large cutout for the pipes and canisters to be installed and removed for maintenance. It is also the air entrance for the tunnel to help cool the canisters and pipes.

Fuse77 KS Canister tie-downs. Heavy Duty ½ wide cable tie-wraps cut to size with .06 aluminum simple l-brackets and back plate.

Fuse78 Close-up of mounting ends for the tie-downs.

Fuse80 Inside fuselage mounting of canister hold-downs. Number 8 sheet metal screws into the hard ash and number 8 flat-head screws through the landing gear plate from the underside.

Fuse81 Canisters and pipes assembled

Fuse82 Smoke tubing attached to the header pipe.

Fuse83 Pipes and canisters installed. Breather tube attached to the carb and the smoke tubing attached to the “T” fitting. The overflow / vent for the smoke and gas tank are visible with silicon protective sleeves attached to protect them from the heat of the canisters.

Fuse84 Another view of the smoke lines going into the pipes.

Fuse85 Number 8 screw up through the landing gear plate to lock-down the canisters.

Fuse86 Top view of the access area for the canister mounts.

Fuse89 Top view into the motor box – on the right is the smoke servo, smoke valve, and throttle servo. On the left is the B&B smoke pump.

Fuse91 Another angle of the front-end.

Pipes1 These are drawings for making the canister hold-down straps.

Pipes2 This is a drawing of the ½ poplar hard mounts that attach to the landing gear plate.

Pipes3 Layout of the pipes for a DA150. it is important to keep the header pipe length as long as possible for the best motor transition. In the case of the Extra 330 the header pipe length was 13 inches.

The Finished Plane

The plane is finished! The CG was setup 5 ¼ back from the leading edge at the tips. The battery packs were used for balancing and ended up under the rear of the canopy. Painting was done using the PPG OMNI basecoat clear coat method that turned out great. The checkerboard on the cowl and swirl on the spinner were a bit of a challenge but worth the effort. The clear coat also seals the thin gold pin stripe on the cowl that makes clean up a lot easier. The 40% Patty Wagstaff doll looks great in the cockpit and the plane looks and flies outstanding. Another success from Carden Aircraft. A special thanks to Dennis and Caroline. I would also like to thank Dave from Desert Aircraft for his support with the motor and pipe setup.