18mm Aurora Clipper Instructions

18mm Aurora Clipper Rocket Glider Kit

​The 18mm Aurora Clipper RC Rocket glider kit is an 18mm powered version of our classic most popular kit and  features a sleek futuristic looking design.  It features a low mounted delta wing with dihedral, a plastic nose cone, white tubing for the body and depron wing and tail surfaces.   It has a light wing loading giving it a very nice glide and easy/stable boost, and the dihedral helps keep it level unless you give it a turn command.   Construction is very simple and takes about an hour and a half. Wing elevons are pre-hinged and spars are pre-installed.  The body tube is pre-slotted for the tail surface and rail buttons are side mounted to avoid catching on the ground during landing. The model boosts to around 250-300′ and has a very gentle glide of around a minute in dead air.  You will need two 7-9 gram type servos, two lightweight 8-12″ servo extensions, a receiver, and a small 500mah single cell lipo battery.  You will need a transmitter with delta or elevon mixing.   Cut vinyl decal sets that will fit this model shown are available HERE .   Select the Large size, not the “small” size.  Specs:  30″ length, 23″ wingspan, 6.5 oz rtf, for 18mm D2.3T composite reloadable motors.

CG location for rocket flight: 10.5″ measured forward from the trailing edge of the wing.  This should be measured with a loaded rocket motor and battery installed as you would be ready to launch the model.

Please refer to the General Information Link above then read the instructions completely before starting assembly. The assembly photos are for general reference but may not include every step in the instructions. If you want hardcopy to work from, all you have to do is click/drag/select and copy all of the text below, open word and paste with “keep original format” and it looks exactly like it does online then you can print it.

Build video below shows a slightly different order of mounting the wing and tail but the order in my written instructions below I feel are slightly better.  They both work but it’s easier to keep the stab aligned vertically with the wing dihedral with the written method.

Unpacking your kit:

The kits are packed to protect them in shipping, but the contents are fragile so unpack carefully.  Carefully cut the tape holding the tubes in the box, then unwrap/lightly cut the plastic wrap to free the tubes, the spar may be packed in the tubes and the baggie with the little parts and nose cone will be in the tubes as well.  Carefully cut the tape holding the cardboard wing protector in the box and carefully remove it, don’t pull hard or bend it.  Then carefully cut the tape holding the cardboard top piece to the bottom.  There may be some sticky tape holding the cardboard to the bottom cardboard piece, carefully peel it being sure not to bend anything.  Once the top cardboard is free you can see the foam wing/tail parts, there are little fragile pieces in here, so unwrap carefully.  It may be best to use an exacto to lightly cut the plastic wrap and carefully remove it without cutting into the foam.  Make sure everything is free before you remove the pieces to avoid breaking anything.  Kits contain one or two scrap pieces for repairs if you damage anything in construction or flight, just cut and patch in a spare piece of the foam if needed using foam safe CA+.

Welcome to the world of rocket boosted radio control gliders.  This is not a model for a novice RC pilot, but anyone who is comfortable with RC flying of a medium speed model should be fine.  Read through the instructions, look at the photos and be sure you understand the step before commiting to cutting or glue.

Aurora Clipper  Rocket glider instructions

Identify all pieces, the kit should contain:

1  wing  taped together

1 Nose Cone

1 vertical stabilizer

2 control horn​s w/pushrods

3 2.75″ long foam strips for centering the motor tube.

1 Body tube or 2 Body Tubes and a coupler​

Motor mount

Velcro(for battery and rx/bec attachment)

2 Rail buttons with t nuts/screws

Lead weight

Spare depron

Notes before starting:

Reference to glue, CA, or CA+ means foam safe CA+, normal CA+ will melt the foam!  Normally you need to use accelerator to get the CA to set on the foam since there is nothing for it to soak into and activate.

I bevel the edges of the foam surfaces before assembly which helps reduce drag and makes the model look nicer.  I simply use a sharp Xacto knife and a metal straight edge to cut a 1/16-3/32″ wide 45 degree bevel on the edges on both sides of the wing and tail, on the curved areas I do it freehand and touch up with a little 320 grit sandpaper.  If you decide to sand the edges, use a block and a VERY light touch and do small areas at a time to avoid the paper catching the foam and tearing it.   Do any shaping before assembly.

Epoxy is not needed in this model.  It is designed to be assembled ONLY with Bob Smith foam safe medium thick CA+ and accellerator or equivalent.  Weight is critical and the model is designed for the thrust and flight loads.  Weight in the rear end is bad and will require additional weight in the front of the model.

Notes: This 18mm model is very weight critical, use 7-9 gram servos and the lightest servo leads you can find.  I would not paint the model to save weight.

Assembly:

***Note, there are two versions of this kit depending on parts availability and shipping boxes I can get, one has two tubes and a coupler and on this version the wing mounts a little forward of the rear of the tube so the CG will come out correct. The other version has a single long tube and on this version the wing mounts even with the rear of the tube so the CG comes out correct, in both cases the tubes are marked “rear” where the wing should align at the rear, pay attention to this. 

1. Install the rail buttons at this time in the tube with the pre-punched holes.  Insert a t-nut from the inside of the tube, then install a plastic washer, then the small collar, then the other washer and secure with the screw.
2. If your kit came with two body tubes and a coupler, glue the coupler into the tube with the rail buttons, it will go into the end without the slot, it will slide in till it hits the rail button, about 1.25″, then glue the short tube onto the coupler making sure the small arrow marks are aligned on the two tubes, that will ensure the wing marks are properly aligned.
3. Glue the 3 foam centering strips on the motor mount tube.   You will glue two strips on either side and one on the bottom.  The lines were pre-marked but on some they are not perfectly aligned, use your eye and make sure they are approx as shown in the picture.
4. Test fit the vertical tail into the slot and make sure it fits.  Make sure the tail is straight with no warps, bend carefully by hand to straighten it if needed.  Glue into the slot using foam safe CA+ making sure the tail is more or less straight up and down in the tube.
5. The wing will be unfolded and mounted on the bottom of the body tube.
6. Apply a squiggle of glue about 1/2  wide to the body tube wing line, the wing joint, and 1/2″ on either side of the wing joint.
7. Lay the body tube so that the stab points down and hangs over the end of your table/bench.
8. Lay the wing upside down onto the body tube making sure the rear of the wing is even with the “rear” mark on the body tube line and the front and rear longitudinal alignment lines are in line with the center taped wing joint.   Tape the front and rear of the wing in place with masking tape to hold it in place.
9. Before the glue has set flip the model over and block up each wing tip so they are even, the actual amount, 1.5″ to 2.25″ or slightly more is ok, the pre-cut bevel on the taped joint helps to set the max dihedral but there is some variation since I cut these by hand,  just so that they are about the same on each side, and then use a triangle to make sure the vertical stab stays perpendicular to the table.
10. Once the glue has set, apply some glue into the wing/body tube joint on each side to make sure is is secure, I squeeze some glue about every inch along the joint on both sides and make sure it is set before continuing.
11.  Test fit the motor mount, You will need to sand the tabs glued on the motor tube so that it fits under the vertical fin tab and inside the tube on the sides.  Do so carefully till it will insert fully and is recessed about 1/2″ from the rear of the body tube.  Glue the motor mount into the rear of the model.
12. For flight, You will apply a small piece of masking tape to friction fit the motor to keep it from falling out after boost.  The rear closure ring on the reloadable motor will keep it from sliding forward.
13. Glue each control horn/pushrod in place on the top of the control surfaces using the pre made holes.  The control horn holes should be pointing toward the front of the model.  Note the pushrods are closest to the center of the model and angle inward slightly.  There is a left and right pushrod assembly.  Repeat on the other side.
14. Put some CA on the control horn prongs where they stick through on the bottom of the elevon, this locks it in place

The basic construction is now complete.

Radio Installation

Note:  Your radio needs to be configured for Delta mixing, this means that the servo arms will move the same direction during elevator stick movement and opposite for aileron stick movement.  Connect your servos to the receiver one in the aileron connection and one on the elevator connection and apply power.   Use a servo arm at least 9/16” long and with holes small enough that there won’t be slop with the pushrod wire when installed.  I use the hole furthest out on the servo arm, to maximize movement. On some servos there are a long two-ended servo arm, you can trim off one end if needed to get sufficient length.   Zero out any trim settings on the transmitter. The model once the motor has burned out is nose heavy and flying wings lose pitch authority when nose heavy so you want as much up elevator travel for trim/flare as possible.

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1. Connect a servo to each pushrod.  If the pushrod is too tight, you can use twist an exacto knife in the servo arm hole to make it larger, but be careful and do not make it too large.  Once connected, tape each servo in place so that the control surfaces are centered.  Look at the model from the rear.  Moving the transmitter stick back(up elevator) should move both elevons up.  Moving the transmitter stick to the right should move the right elevon up and the left elevon down.   If you can’t get the servo reversing to give you the right polarity try swapping aileron/elevator inputs to the receiver or turning the servos over and swapping the servo arms to the other side of the output shaft.  If that is correct, continue.
2. Mark where the servos will inset into the body tube on each side and cut a pocket to fit the servos so that the elevons will be neutral when the servo is inset into the body tube.
3. Connect your servo extensions to each servo that are long enough to reach the front of the body tube and then route the leads forward and re-connect to the receiver.
4. With the radio still on, put a small amount of glue on the servo, being careful not to get any near the output shaft. And set it in place in the pocket keeping the control surface centered.  Do the same to the other side.  Make sure the glue is set before continuing.
5. Make sure the control surfaces are centered, use trims if needed.  Now measure the control surface movement.  Full elevator movement should be 1/2″ in each direction, aileron movement should be 3/8″ in either direction.  Since the model will be nose heavy, extra elevon movement helps to give sufficient authority during glide.
6. If you have a flap/elevator mix you can program up elevator to a switch setting.  The model needs approximately  3/16” of up elevon during glide.  Alternatively if you have flight modes you can set up flight modes so that trim is unique to each mode, that way you can pre-set boost and glide trim for each mode using the xmitter trim tabs.   If you can’t set the up elevator trim to a switch on your radio you’ll have to manually put in boost and glide trim which is hard to do while flying the model.
7. If you use the stickershock vinyl, once applied, use a hair dryer on hot to soften the vinyl and press it down into the foam and cardboard surfaces and it will adhere very well.  Make sure not to warp the foam especially on the vertical stab.
8. You can use a fine line sharpie pen to add panel lines if desired.
9. I do not recommend painting the wing and body to save weight in this particular model.  Cone can be painted with any paint, lightly scuff the plastic with 400 grit sandpaper and clean with alcohol before painting.
10. Insert your heaviest loaded rocket motor into the motor mount
11. Use the included velcro to attach the receiver and battery inside the nose cone or body tube.  You may wish to tape the receiver and battery in place during balancing to determine the best location before securing them with the velcro to avoid adding extra nose weight.  If your model comes out tail heavy move the components as far forward as they can go, if nose heavy move them back etc.
12. Once secured, if required glue pieces of the included lead weight  in the nose or tail as needed to balance it.  Do not try to fly the model with it balancing it behind this point.  The adage is, a nose heavy model flies poorly, a tail heavy model flies once.

Flying:  See the General Information link at the top for flying instructions.  Be ready on the first few flights to keep the model straight till you have the trims set perfectly for boost and glide.