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Last Updated: March 01, 2008 - 01:37:46 PM

HET-RC - ME-262 Twin EDF Jet
By Carl Tulanko
November 05, 2007 - 07:56:55 PM

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The HET-RC ME-262 Twin Minifan EDF jet as it comes from Markos at Warbirds-RC

Opening the box reveals well packed contents

All the parts shown are included in the kit, even fixed landing gear

This kit will be retrofitted with some of the "New" RA-260 Retracts from Airpower and Warbirds-RC

Opening the main bag reveals all the components necessary to get these air retracts flying

The retract units themselves are very small, however, they are stout. The units are made from very thick aluminum alloy and are much sturdier than other brands of retracts we have used in the past. They also come with 1/8" gear wire

The entire Airpower RA-260 retract setup weighs only 3.5oz and that includes the 1/8" gear wires and all air assist accessories

Construction begins by finding the location of each wing Nacelle. A piece of cardboard is included in the kit and is 110mm wide, which is a bit too wide. Hold the cardboard flush with the end of each wing and draw a reference line

Install a nacelle on each wing up to the 110mm line. Make sure you use the correct nacelle as there is one for each side

Measure the side of the nacelles at 108mm from the end of each wing root

The 108mm measurement moves the nacelle closer to the fuselage as the original 110mm caused aileron binding agianst the rear of the nacelle as shown

Draw a new outside line, which should be 2mm closer to the wing root. Make sure the rear of the nacelle clears the Aileron area

Draw on the top of the wing the location of each nacelle

Measure 1/8" inside the outer line on the bottom of the wing and cut to remove the covering material

Cut along the leading and trailing edge, making sure you leave a good 1/8" or more for re-covering

Remove the bottom covering as shown

The covering reveals the fixed gear mounting block, which is used as reference for retract installation

Measure 3 1/4" from the root of the wing to the rear side of the hardwood block and make a mark

Measure 7/8" from the rear of the block and mark this location

Make a second mark at 7/8" as shown

Draw a line through both the 7/8" marks to the root of the wing

Draw the horizontal top line at the 3 1/4" mark across as shown

Cut the Main Door Cutout pattern from the templates and place the back of the door along the vertical line you drew and the top should be lined up with the 3 1/4" horizontal line

Transfer the front pattern of the door to the wing as shown

Mark and draw a second line at 1/8" past the first line to allow for the thickness of the Secondary Spar

Cut the balsa from the area that was just marked

Remove the balsa sheeting and foam from the area

Check your measurement and make sure it shows 3 1/4"

The Trailing edge of the block to the rear should measure 1" as shown

Use an exacto knife to cut into the hardwood block along the door pattern line

A chisel cutter can be used to cut loose some of the wood

An Exacto knife can be used from the side of the block to cut the rest of the length

Once cut, remove the excess wood

Cut away the remaining block to the door line using a chisel knife

Sand the area smooth to remove splinters and burrs

Use a hobby saw and cut the root rear spar down to the balsa. Try to keep the cut parallel to the main spar hole in the forward area of the wing root

Cut the front root area in a similar manner

use a knife to cut along the inside of the wing root and remove the excess

Sand the bottom of the area flush to the wing sheeting

Insert a piece of 1/8" ply sheeting and draw a line on the sheeting. Cut the Secondary Spar to length as shown in the templates

Cut a piece of 1/4" x 3/8" hardwood block to a length of 1 7/8" ; Note that the wood shown in the pic is 3/8" square and had to be cut to the correct 1/4" x 3/8" dimensions

Draw a line along the block as shown to match the one in the templates

Sand the surface smooth

Cap the top of the block with a 1/16" thick piece of aircraft ply

Clamp the assembly until the epoxy sets

Use a knife to cut away the foam underneat the top side of the wing as shown

Cut back the foam about 1" or more; clean up the hole for the aileron servo wires

Remove the extra piece of balsa as shown. Cut it from the fuselage opening to the outside top of the hardwood block

Cut a 3" long piece of 3/8" square hardwood and use it to mark the foam on the right side as shown. Remove the foam below the line so the block can sit recessed in this area under the wing sheeting and even with the top opening

Install the main spar

Install the wing in the fuselage

Transfer the outline of the wing's cut out area to the fuselage

Use a sharp knife to remove this area from the fuselage. Sand the inside edges smooth once finished

Measure 1/4" down from the seam of the fuselage on the bottom of the jet and draw a line parellel to the seam

With the wing installed flush, make a line from the rear of the wing opening to the fuselage

Make a line from the front of the wing opening to the fuselage, matching the angle

Install the template with the top at the 1/4" from the seam horizontal line and the bottom between the two marks you just made. The rest of the pattern should align with the wing door area as shown

Transfer the pattern to the fuselage area

Carefully cut out the pattern in the fuselage. This will take some time, possibly an hour or more and may take 30-40 passes with an exacto knife on each side. It takes a couple blades to cut through the entire area. If you run into a glue area, try to pop the fuselage free of the glue rather than cut through the glue, which will be reinforced later. Also note that one side will expose some of the main spar support plywood and glue. Take care not to cut into the ply

Lightly sand the area that was cut out and clean it up

Measure in 1/8" from the front inside door run as shown

Cut the balsa to the elbow, but leave the foam core in place

Cap the area with a 1/8" wide by 1/16" thick piece of basswood strip. Epoxy it in place

Cut out the wing door from the pattern

Check the fit on the door

Add Epoxy to the Retract wedge top and outside

Install the wedge as shown, with the inside of the wedge aligned with the bottom end of the harwood block

Cut a second wedge, 3" long from 1/4" x 3/8" hardwood using the supplied pattern

Cap the wedge on the top with a 1/16" thick strip of aircraft ply

Clamp the assembly and allow the epoxy to set

Install the secondary spar, the long wedge and the retract and check their position. Install the fixed gear wire in its hole and check that the angle of the retract wire is similar to the fixed wire ash shown. Also, slightly sand the inside of the long wedge if the retract is too tight

Use a screwdriver to push the roll bar level forward in the retract and then fold the gear wire into the wheel well. Check that the wire runs paralled to the wing door area and that is is fairly centered in the wheel area

Apply epoxy to the 3/8" square block and install in in the opening you cut so the bottom is pressed against the inside of the root spar

Use the secondary spar to hold it in place while the glue sets.

The block support is shown glued into place

Apply epoxy to the side and bottom edge of the secondary spar and install it in place. Do not apply epoxy to the bottom part of the spare that is exposed and plugs into the fuselage

Clean up all excess epoxy

Apply epoxy to the long wedge bottom and the one side facing the spar

Epoxy the long wedge in place, so the back is even with the other wedge and the bottom should come near the end of the wing root

Clean up all excess epoxy with a scraper and paper towels

Install the AirPower RA-260 retract. It should just fit between the two wedge blocks

Cut another piece of hardwood block to fit behind the two wedge mounts

Apply epoxy to the area as shown

Install the cross block support and epoxy in place

Clean up any excess epoxy

Lightly sand the secondary spar so it is flush with the wing sheeting

Position the retract so the front of it is 1 15/16" from the root edge of the wing as shown

Use a pencil to mark the location of each mounting hole

Use a punch to start the mounting holes

Place a piece of masking tape on the end of your drill bit, no more than 3/8" from the end. Do not drill past the tape as this will act like a depth gauge so you do not drill through the top of the wing. Drill the four mounting holes with a 1/16" drill, angling the bit from the side view so it is perpendicular to the wedge

Temporarily install the door and mark its top location as shown

Fit a 1/32" ply plate as shown, just above the marks you made

Place a EZ-Hinge in position and mark the areas that need trimmed down to size the hinge to the hole

Measure and draw a centerline down the hinge

Place half the hinge over a 3/16" thick piece of balsa and trace the outline of the hinge to the balsa. Note that the hinge sides were cut slightly angled to allow for clearance on the sides

Use a ruler to scrape away and compress the balsa topcoat on the block so the hinge is recessed and the top of it sits flush with the balsa block

Round the back bottom side of the balsa block so that the Aileron Servo cable will not hang up when passed by it

Tape up half the hinge to the centerline, then epoxy it to the balsa

Cap the top of the hinge with the 1/32" ply coverplate while the epoxy is still wet

Install the block while the epoxy is still wet under the top wing area so the front of it comes even with the top of the door as shown. A piece of tape is used to hold the ply plate and balsa block in position until the glue sets. Use a ruler underneath as shown to insure the block is pressed up against the inside of the wing

Cut a piece of 1/8" square basswood to a length that allows the inner retract screw to still be installed

Epoxy the stick in place and use the door to measure how low to place the stick. The top of the door should be even to the wing's surface

Cap the top of a scrap piece of 1/8" balsa with some 1/8" basswood stick

Measure and trim the balsa plank to height and cut to size. Make sure it sits recessed below the top of the wing

Sand a bevel at the end of the balsa plate

Glue the plate in place, with the basswood stick on top as shown. IT will cover the wing foam and should sit recessed so the door is flush to the wing

Clean up the excess epoxy. The plate will cover the wing foam and should sit recessed so the door is flush to the wing when placed over this stop plate

Apply some epoxy to the fixed gear slot in the hardwood block

Use some scrap 1/8" square basswood stick to fill in the space

Cut the excess basswood so it blends in with the angle of the hardwood door cuts

Epoxy a piece of 1/16" x 1/8" basswood stick at the angled location to prevent the door from receding to far, but ratheer give it a landing for which to rest

Place the door over the retract area and check for fit. It should be recessed enough to sit below the surface of the wing. Sand the landings to fit if necessary

Cut a piece of 1/8" ply to a width of 1/4" and to the length and shape as shown. this will act as door retention and an alignment guide

Bevel both the front and rear inward to allow for alignment of the door

Install the retract and colapse the gear. Rub a pencil across the top of the gear wire as shown

Position the door bracket in place and lift the gear wire

The gear wire transfered its location to the bracket

Cut a short piece of 1/8" ply and epoxy it in place to the back side of the gear(right)

Cut a second block and use it to wedge the gear wire between it and the other block. Apply thin coat of CA to the top of the two blocks to prep them for drilling

Drill 1/16" holes through the center of each small block and out the bottom of the bracket. Epoxy a small diameter piece of elastic cord in one hole, then when set, epoxy the other side in, keeping some tension on the cord so it dries while semi-taught

Slip the asssembly over the gear wire. Use small pieces of masking tape to keep it from shifting position on the wire

Apply epoxy to the top surface of the bracket assembly

Use tape to hold the gear wire down and out of the way

Position the door in its opening and tape in place

Tape the top of the door over the hinge

Lift the gear wire until the bracket touches and glues to the inside of the door. Allow the glue to set

Door Bracket is shown correctly installed

Locate the area of fuselage you removed for the gear and wheel; this will be used as the doors. Trim the top of the fiberglass door as shown and keep both pieces

Measure 1" from the inside flat area of the door and cut the smaller door away from the larger

Lightly sand the smaller door to smooth the ends

epoxy a piece of 1/16" thick ply that is 1/16" wide along the short side length of the door

Make a wire hinge from 2-56 pushrod and bend as shown in the templates

Place the wire in position as shown and cut an inner 1/16" ply piece at least 1/8" wide. It will be placed above the wire to wedge and hold the wire in place

Cap the assembly with a final piece of 1/16" thick ply wide enough to cap the assembly

Ply ends are shown glued in place

Mark a center line on the wide ply plate. Use a saw to slot only down to the hinge.

Bend a piece of micro pushrod as shown

The pushrod is a fraction longer so it can push into the thin ply brace at the bottom, then slide into the slot you cut with a saw as shown at the top

Cut a small piece of 1/16" thick x 1/4" wide ply so it fits between the two ply braces. Slot it so it will cover the micro wire

Epoxy the short ply over the micro wire as shown

Bend the wire 1/14" past the rear of the door

Position the door temporarily in place. Remove any fuselage glue that will get in the way over the next few steps