Introduction

Deperdussin flightline at Reims airfield near Bethany, France.

At daybreak on July 25, 1909, Frenchman Louis Bleriot succeeded in making the first successful crossing of the English Channel. His small monoplane made the 23 mile flight to Dover in 37 minutes despite an overheating 25-horsepower Anzani engine. Just one month later over 500,000 spectators attended the world's first great airshow at Reims, France. There the French airplanes built by Bleriot, Voisin, Antoinette, and Farman dominated almost all of the racing events (although American Glenn Curtiss edged out Bleriot in the premier Gordon Bennett Race).

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Bleriot's cross-Channel flight and the Reims Airshow excited Europe as nothing else had, but no one was more excited than wealthy French industrialist Armand Deperdussin. Immediately he founded his own aircraft-building company, the Société Pour Aéroplanes Deperdussin (SPAD) at Betheny near Reims in 1910.

Not a designer himself, Deperdussin hired a capable young engineer named Louis Bechereau. Together they produced some of the most advanced racing airplanes of the pioneer period.
Pierre Lacombe flying his Deperdussin in 1911.

French pilot Jules Vedrines signals his crew to
release his straining Deperdussin for another race.


By 1912 Deperdussins were winning all the important races and setting new speed records at nearly every race. French pilot Jules Vedrines won the 1912 Gordon Bennett Cup with a Deperdussin, being the first person in history to fly faster than 100 mph. France's Maurice Prevost won both the 1912 Gordon Bennett Cup and the 1912 Schneider Trophy with a Deperdussin, setting a new world speed record of 126 mph in the process.

In spite of their winning racing record, and receiving lucrative contracts to build airplanes for the French government, the company went bankrupt in 1914 when Deperdussin was arrested for embezzling 32,000,000 francs from his company. The company was reorganized with Deperdussin's former rival Louis Bleriot in charge. Bleriot renamed the company Société Pour L'Aviation et ses Derives (SPAD) and retained Louis Bechereau as Chief Engineer. The reborn SPAD company went on to make some of the best fighter airplanes of World War I, building more than 5,600 aircraft for France and other countries.
Aeroplanes always drew a crowd in 1910.



Later model 2-place Deperdussin for the military.

Artist Charles H. Hubblell’s painting of the Deperdussin.


The SIG Deperdussin represents a semi-scale rendition of the early Deperdussin airplanes of 1910 to 1911. This kit is not intended for beginning modelers. However, most intermediate modelers with average building skills will find this kit easy to build and fly. These instructions assume that you are aware of the importance of using the correct type and amount of glue, how to make proper wood joints and how to fly R/C models.

Using the radio equipment, battery pack, motor, and propeller recommended in these instructions, you'll find the Deperdussin is remarkably stable and easy to fly. Designed to be flown indoors, this model can also be flown outdoors in no-wind conditions. Its light weight and low wing loading do not lend themselves to windy conditions. Between flying sessions, you will enjoy displaying this intriguing and unusual airplane in your workshop, den, or office - it's a real attention grabber!

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Motors And Propellers

We recommend the SIG EPU001 ELECTRIC POWER UNIT to power the Deperdussin. This motor and gear box system consists of a high-quality brushed electric motor, an integral 7:1 ratio gear box, and a 10 x 5 electric style plastic propeller. Used with a 7-cell 350mAh Nicd battery pack, or 7-cell 500mAh Nimh battery pack, this system has provided good power margins and scale-like speeds in the Deperdussin, along with very good flight duration. The SIG EPU001 power unit is actually manufactured by GWS, which they sell as their IPS-DX2BB-B (note: Maxx Products also markets the exact same power unit as a MAXX EPU-7).

Radio Equipment, Speed Controller, Battery Pack, and Connectors

One of the very reasons that indoor models such as the Deperdussin are now possible is the fairly recent availability of good quality, reasonably priced light-weight micro receivers, servos, and speed controllers (ESC’s). Up to this time, such equipment was only available from small, highly specialized sources at relatively high prices.
Here are the airborne radio system components we’ve used in the Deperdussin.

ItemWeight
Maxx Products (MPI) Micro Receiver8 grams
Maxx Products (MPI) #MX-30 Servos7 grams each
Maxx Products (MPI) #MX-9104 Micro ESC1 gram
7-cell 350mAh Ni-Cd Battery Pack95 grams
7-cell 500 mAh NiMH Battery Pack96 grams



A 7-cell battery pack is used in the Deperdussin for two very good reasons. The first has to do with the C.G. realities. With virtually no nose moment, the Deperdussin needs a substantial battery pack to get the airplane to balance and the 7-cell pack does just that. The second reason is flight duration. With throttle management, the 7-cell 350mAh Ni-Cad battery pack keeps our Deperdussins flying for anywhere from 8 to 12 minutes. We’ve also used 7-cell 500 mAh NiMH (Nickel Metal Hydride) battery packs with good results. In general, the difference between this type of cell and the 350 mAh NiCad cell is that the NiMH pack seems to deliver a little less power with some incremental increase in duration. Both types of cells weigh the same, so they are both usable. Last, the battery pack should be configured in the "hump" shape - four cells on the bottom, three cells on top. This layout offers the most mass in the least amount of space and this is very helpful when making small changes in the C.G. location, if needed.

For maximum flight performance, indoor R/C models require attention to the weight of everything they must carry aloft, including connectors. We used and like the small 2-prong Dean’s connectors for connecting the battery pack to the ESC. There are other connectors available on the market that are also suitable for the Deperdussin.

Last, use a radio system with an excellent transmitter. We find that features such as servo throw adjustments (EPA), servo reversing, servo sub-trim adjustments, etc. are very helpful in setting up and flying the Deperdussin.

Required Tools
A selection of glues
  • SIG Thin, Medium and Thick CA
  • SIG Thin CA Applicator Tips
  • SIG Kwik-Shot CA Accelerator
  • Heat-Activated Covering Adhesive, such as SIG Stix-It or Solarfilm Balsaloc.
A selection of hand tools, such as
  • Regular size and miniature screwdrivers
  • Pliers (flat nose, needle nose, round nose)
  • Tweezers and/or small hemostats
  • Hobby knife with sharp #11 blades
  • Sandpaper - assorted grits
  • Modeler's "T" pins
  • Power drill and hand "pin vise" (for small diameter drill bits)
Assorted drill bits, including
  • .031" (1/32" or # 68)
  • .046" (3/64" or # 56)
  • .063" (1/16" or # 52)
  • .078" (5/64" or # 47)
  • .093" (3/32" or # 42)
  • .109" (7/64" or # 35)

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Paint

Since fuel proofing is not an issue with electric powered airplanes, the only reason to paint any part of the Deperdussin is to improve the scale appearance of the model. And because light weight is so important in an indoor model, we've tried to keep the painting on the Deperdussin to a minimum. Too much paint, or the wrong kind of paint, can add unnecessary weight in a hurry. Do not use thick, heavy paints like epoxy or enamel on these large areas of the model. We prefer thinned SIG Supercoat Dope or "waterbased acrylic craft paint" (see note below). One coat is usually all that is necessary. A completely filled glossy paint job is not necessary or desirable, and it's too heavy for this type of model. One coat usually achieves the "old time" look we are after.

* Water-Based Acrylic Craft Paint: These inexpensive paints are sold in the craft departments of stores such as Wal-Mart, K-Mart, and similar outlets. They seem to be manufactured under many different brand names, such as Delta Ceramcoat™ and Apple Barrel Colors™. They are available in a huge variety of colors. We found that thinning these paints with equal amounts of water produced nice results, when either brushed or sprayed, with very little weight build-up. Clean-up is also easy, using just warm water.

A few painting guidelines:
  1. Paint the landing gear struts, cabane struts, and tail skid a brown color to look like varnished wood.
  2. The dummy engine, dummy gas tank, and other molded plastic parts can be painted with the water-based acrylic craft paints, or they can be painted with Testors Model Master™ enamel paints for plastic models (using the spray can products whenever possible). The engine crankcase was painted "steel" color. The cylinders are black. The dummy gas tank looks great painted copper, just like on the full-scale Deperdussin. Use your imagination and keep in mind that flat or semi-gloss colors usually look more realistic than high gloss paints.
  3. We've tried a variety of colors for the balsa wheels on our prototype Deperdussin models: gray to simulate steel wheels, brown for wood wheels, or black for painted rims, which was also common. It's your choice and a matter of personal preference.
  4. The amber colored surgical tubing that is provided for the tires can be easily dyed black with regular household variety Rit Dye™. That looks good with gray or brown wheels.

COMPLETE KIT PARTS LIST
Balsa Sticks & Sheets
21/16"x1/4"x12" Rib Stiffners 41/8"x1/8"x42" Fuselage Longerons 71/8"x1/8"x36" Fuselage, Stab, Elevator, Fin, Rudder, Wing Tip Braces, LG Cross Braces 11/8"x1/4"x36" Cabane Struts
21/4" dia. x24" Balsa Dowels; for Wing Trailing Edges 21/4" dia. x30" Balsa Dowel; for Wing Leading Edges 11/4" dia. x7-1/4"" Balsa Dowel; for L.G. Spreader Bar 21/32"x1-5/8"x18" Fuselage Side Sheeting
11/32"x3"x3" Fuselage Bottom Sheeting
Laser-Cut Balsa
11/32" thick Sheet #1; FT1, FT2, WSP 11/32" thick Sheet #1B; Fuselage Bottom Sheeting 11/16" thick Sheet #2; F2, F3, F4, F4A, F5, F5A, F6, F6A, F7, F7A, F7B, F8, F8A, F8B, F9, F9A, F9B, F10, F10A, F10B, F11, F12, F13, FG1, FG2, FG3 21/16" thick Sheet #3;WHL, LG2, LG3, LG4, LG5, BTM, FD1, FD2, SW2
21/8" thick Sheet #4; W1, W2, W3, W4, W5, W6, W7, W8, G1, G2, G3, G4, WHB 11/8" thick Sheet #5; G5, S1, S2, S3, F14 11/4" thick Sheet #6; FDB, RDB
Laser-Cut Plywood
11/32" thick Sheet #7; CHN, WSF, WHC, WRT, LG1, FD3, SW1 11/16" thick Sheet #8; Motor Mount 11/8" thick Sheet #9; F1, SW3, SW4
Hardwood
210" Bamboo Sticks; for LG Mounts, Tail Skid 11/8"x3/16"x3" Basswood Stick; for Rudder Servo Mounts 11/4"x3/16"x3" Basswood Stick; for Elevator Servo Mounts
Wire Parts
1.020" dia. x12" Straight Wire; for Rigging Hooks 2.046" dia. x1-1/2" Straight Wire; for Axles
Hardware
7#1 x3/8" Sheet Metal Screws; for dummy motor 4#2 x1/4" Sheet Metal Screws; for motor attachment 30090 x1/8" Round Brass Machine Screw; for pilot 20090 x1/4" Round Brass Machine Screw; for steering wheel
10090 x1/2" Round Brass Machine Screw; for steering wheel 40090 Brass Hex Nut; for pilot(3) & steering wheel(1) 100090 Brass Washers; for pilot(6) & steering wheel(4)

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Miscellaneous Parts
2Molded ABS Plastic Dummy Engine Halves 1Molded ABS Plastic Fuselage Top Deck 1Sig Easy Hinge 321/16" od x 1/4" Aluminum Tubes; for wing rigging points & swage tubes
41/4" id x 1-5/16" Aluminum Wing Mount Tubes 110 ft. Monofilament Pull-Pull Line 18 yds. Elastic Thread; for rigging wires 12 ft. Dacron Thread
122" Rubber Tubing; for tires 1Pilot Sheet 13/4"x3" long Velcro® 119-1/2"x90" Red Covering Material
1Decal Sheet 1Full-Size Plan 1Instruction Book

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Use a pencil to mark each of the parts according to these diagrams.

NOTE: When it’s time to remove a part from a sheet, use a sharp #11 hobby knife to slice through the small bridges that hold the part in the sheet. Do not try to push the parts out of the sheet without first cutting through the bridges, or you may end up with a lot of broken parts.




FUSELAGE CONSTRUCTION

1a.

Identify laser-cut balsa sheet #2 by comparing to the "Key To Laser-Cut Parts" diagrams. Sheet #2 is 1/16" thick balsa and contains fuselage formers F2 through F13.

b.

Use a fine point pen to mark the part number of each part right on the wood.

c.

Use a sharp #11 hobby knife to cut through the retaining tabs that are holding each part in the sheet, and then carefully remove the parts from the sheet. Use one or two light swipes with a fine grit sanding block to remove any remnant of the retaining tabs that remains on the sides of the parts. Handle the parts carefully ... being only 1/16" thick they break easily!

d.

Repeat steps a, b, and c to remove former F14 from laser-cut balsa sheet #5.

e.

Repeat steps a, b, and c to remove former F1 from lasercut plywood sheet #9.

2.

Formers F4, F5, F6, F7, F8, F9, and F10 need to be reinforced with their corresponding A and/or B parts. Be sure to line up the common edges of these parts carefully when gluing them together.

a.

Glue F4A along the top of former F4.



b.

Glue F5A along the top of former F5.

c.

Glue F6A along the top of former F6.

d.

Glue F7A at the top of former F7, and F7B at the bottom.

e.

Glue F8A at the top of former F8, and F8B at the bottom.

f.

Glue F9A at the top of former F9, and F9B at the bottom.

g.

Glue F10A at the top of former F10, and F10B at the bottom.

3.

The basic framework of the fuselage will be built upside down on the plan. Pin the FUSELAGE FRAME TOP VIEW to your building board and cover with wax paper or plastic wrap for protection.

4.

Pin two 1/8" sq. x42" balsa sticks onto the plan for the Top Longerons. Bend the longerons where needed to follow the plan exactly from former F1 all the way back to the tail end.

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5a. Get a piece of scrap cardboard approximately 3" square to make a downthrust gauge to use while installing the plywood firewall F1. Lay the cardboard on the side view plan as shown, with the top edge lined up with the top of the fuselage, and then mark the angle of the firewall on the cardboard. Cut along the marked line.

b.

Glue the plywood firewall F1 in place at the front of the fuselage. Use the cardboard downthrust gauge to set the proper angle of the firewall while the glue dries.




6.

Glue fuselage formers F2 through F14 in place. Make sure all these formers are glued in perpendicular (90 deg.) to the building board.

7.

Glue the remaining two 1/8" sq. x42" balsa sticks into the appropriate notches of the all the formers for the Bottom Longerons. Double check with the cardboard downthrust gauge to make sure the F1 firewall stays in proper position while you install these longerons.

8.

Cut a piece of 1/8" sq. balsa stick to go in the bottom notch of formers F1 through F6. Glue in place. When dry, unpin the fuselage frame from the building board.

9.

Glue the laser-cut front dihedral brace FDB in place on the front of former F3. Study the plans, including the cross-section drawing, to make sure you understand exactly where it goes.



10.

Glue the laser-cut rear dihedral brace RDB in place on the rear of former F6. Study the plans, including the F6 cross-section drawing, to make sure you understand exactly where it goes.

11a.

Cut four pieces of 1/8" sq. balsa x 9-3/16" long. Glue two of these sticks in the notches on the right side of formers F10, F11, F12, and F13, and glue two on the left side. These sticks create a slot into which the stabilizer will be mounted later.




b.

Use a fine tooth razor saw blade to cut out the small portions of formers F11, F12, and F13 that are inside the stabilizer slot. Touch up any rough edges in the slot with a "sandpaper file".

Modeler’s Tip:
In this instance our "sandpaper file" is a small piece of scrap 1/8" thick plywood with 100 grit sandpaper glued to both sides. This is a handy tool to have in your shop - make several sizes while you're at it.

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12. Trim the tabs off each side of former F14. The purpose of these tabs was to aid in assembly of the fuselage frame. Now that the frame is glue together, the tabs are no longer needed. Trim the tabs off with a knife or razor saw, and then sand F14 flush with the longerons.




13.

Glue fuselage gussets FG1 and FG2 in place in front of former F11. Also glue fuselage gusset FG3 in place in front of former F13.

14.

Inspect all the glue joints in the fuselage to this point and apply more glue where needed. Let dry. Then use a small sanding block with 100-150 grit paper to block sand the flat sides, top, and bottom of the fuselage structure, touching up all of the joints.

15.

Even though we're not going to glue it until after the fuselage is covered, let's make the Tail Skid now.






a.

Choose the straightest of the two 10" pieces of bamboo provided and put a mark 3-1/2" from the pointed end. The 3-1/2" area between the mark and the end of the stick needs to be bent to a curved shape for the bottom of the tail skid, as shown on the plan.
Note: We'll cut off the pointed end later, but for now the excess length will be handy during the bending of the bamboo in the next step.

b.

There are a lot of different ways to bend wood, but for this application we've found that the easiest method is simply to do a "controlled break" of the area we want formed. In other words, we simply bend the bamboo slowly until it just starts to break. Start with the tip of your thumb near the 3-1/2" mark. Bend the stick over your thumb until you feel it start to break. Stop, move your thumb about 1/4" or so further along in the area you want formed, and then bend again. Continue moving along in small increments in the area you want formed, bending it to the point of almost breaking, until you have the shape you want. Don't worry if a few strands of bamboo start to get loose on the outside of the curve. Once you've got the shape you want, thoroughly soak the entire bent area of the bamboo stick with thin CA to re-strengthen it. When dry, sand off any rough spots.

NOTE: Don't worry if the bend in your tail skid doesn't match the plan exactly. No doubt the tail skids on the full-scale Deperdussins were all a little different too.

c.

Cut off the excess 1" or so of the pointed end of the bamboo tail skid to match the length shown on the plan. Sand the bottom tip of the tail skid round.

d.

Cut a 1-3/4" long piece of 1/8" sq. balsa stick to make the Tail Skid Support. Use sandpaper to make the bottom end of the support slightly concave to provide a good joint to the round bamboo tail skid. Glue the tail skid support permanently to the tail skid, making it perpendicular (90 deg.) to the skid.

e.

Trial fit the tail skid on the bottom of the fuselage. You could glue it on now, but we've found it's a lot easier to cover the rear of the fuselage without the tail skid in place. So set the tail skid assembly aside for now.

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16. Two sheets of 1/32" x 1-5/8" x 18" balsa are provided for sheeting the sides of the fuselage from F1 back to F7. The best procedure is to lay one of the 1/32" balsa sheets on a piece of wax paper on your flat building board. Then lay the side of the fuselage down flat on the balsa sheet. As you hold the fuselage down flat against the balsa sheet, start tack gluing formers F7 thru F3 to the sheet. Also glue the top and bottom longerons. Let dry. Then repeat the process to glue 1/32" balsa sheeting onto the other side of the fuselage. When dry, trim, and sand all the edges of the side sheeting flush with the structure.

17.

Cut four pieces of 1/32" scrap balsa x 1/8"x1/4". Glue them on the sides of the top and bottom longerons at the end of the side sheeting at F7. Taper them down to blend smoothly from the end of the sheeting into the longerons. This will make the covering material go on a lot smoother later.

18.

Glue a balsa FD2 fuselage doubler on the inside of both the right and left fuselage sides between formers F4 and F5. Make sure the hole in FD2 is properly located, closer to former F5 than F4, as shown on the plan and in this photo.

19.

Glue a balsa FD1 fuselage doubler on the inside of both the right and left fuselage sides between formers F1 and F2.

20.

Glue the balsa BTM battery mount in place.




21.

Next install the laser-cut 1/32" balsa Fuselage Bottom Sheeting, which runs from formers F1 to F7. This is probably the trickiest part of the entire assembly of this model, but if you follow this proceedure it goes pretty easy.

a.

First glue one edge of the fuselage bottom sheeting in place on one side of the fuselage as shown in this photo. Glue the edge of the bottom sheeting against the edge of the side sheeting. Use only enough glue to get a solid joint and then let it dry completely before proceeding.




b.

When dry, start carefully bending the bottom sheeting around the fuselage formers, one at a time, starting in the middle with former F4. At this point just bend it halfway around the former, to the 1/8" sq. balsa center stick. Hold the bottom sheeting in tight contact with F4 while you apply a small amount of thin CA glue from the inside. When that glue is dry move on to the adjacent former F3 and do the same, tack gluing the bottom sheeting in place to that former. And when that's dry, move on to former F2, and then F1, and then back to formers F5 and F6. After you have the bottom sheeting tack glued halfway around all the formers, then glue the sheeting to the 1/8" sq. balsa center stick.

c.

After the sheeting is glued halfway around all the formers to the center stick, go back to former F4 and trial bend the bottom sheeting the rest of the way around the former to the other fuselage side. Pay close attention to the fit of the bottom sheeting against the lip of the fuselage side sheeting. Most likely you will find that the bottom sheeting is a little too big for a perfect fit. This is because we deliberately made the bottom sheeting a little large to allow for slight differences between models.
Continue trial bending the sheet at each former to check the fit. Make a mental note of how much material needs to be sanded off the edge of the bottom sheet to achieve a good fit. Then use a 100 grit sanding block to sand down the edge evenly, until it does fit properly. Work carefully and gently to avoid breaking the bottom sheeting.

d.

When satisfied with the fit, finish gluing the bottom sheeting completely in place against all the formers and side sheeting. Let dry.

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22. Glue the 1/32"x3-1/4"x3" balsa piece provided onto the opening at the back of the bottom sheeting. Let dry. Then trim and sand the edges of the balsa flush with the bottom sheeting. Note: The grain of this piece goes cross ways on the fuselage.

23.

The fuselage is now ready to be covered. Cover before proceeding.

LANDING GEAR

24.

Carefully remove the following parts for the wheels from the laser-cut sheets:
40 - WSP 1/32" balsa wheel spokes from sheet #1
4 - WHL 1/16" balsa wheels from sheet #4
4 - WHB 1/8" balsa wheel hubs from sheet #5
4 - WHC 1/32" plywood wheel hub caps from sheet #8




25.

Use a #11 hobby knife to cut loose the "pie shaped" scrap pieces between each of the spokes of the WHL parts.

26.

Two of the WHL pieces will be laminated together to form the basic core of one wheel assembly. However before gluing them together, use a flat sanding block with medium grit sandpaper (100 to 200 grit), to bevel the outer edge of each WHL piece. Hold the sanding block at a 45 deg. angle. Bevel only one side of the piece. The purpose of the beveled edge is to provide a groove for the rubber tire to fit in after the WHL pieces are laminated together with their beveled edges facing each other.

27.

It's important to work on a flat surface when laminating the WHL pieces together to insure that the finished wheel comes out flat, so it will roll straight and true with no wobble. First lay a piece of waxed paper down on the flat surface.

Next lay a WHL piece down on the waxed paper with its beveled side up. Position a second WHL piece, beveled side down, on top of the first one. Rotate the top piece so its grain direction is 90 deg. to the grain direction of the bottom piece. This will provide maximum strength to the finished wheel.



Carefully match up the spokes of the two WHL pieces exactly. When satisfied with the positioning, hold the parts flat while tack gluing them together with Thin CA glue at 3 or 4 spots around the outer edge. Put the drops of glue right in the beveled groove. Not too much, just enough to tack glue the WHL parts together. After the glue dries, you can pick up the laminated part and continue gluing along the spokes and hub areas.

NOTE: It's best to use a fine applicator tip (such as SIGSH10220) on your CA bottle during assembly of these wheels. In fact, a fine tip is preferred for the assembly of this entire kit. Building featherlight models like the Deperdussin requires that we change our thinking a bit from the old habits we've used in building much heavier sport type models. With the small parts involved here, it's not desirable to flood a large area with a lot of glue. It's much better to get a little glue exactly where you need it, and a fine applicator tip does that for you.

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28. Next glue a 1/8" balsa WHB wheel hub and a 1/32" plywood WHC wheel hub cap onto each side of the wheel assembly. To insure that the center holes in all these parts are in correct alignment, it's best to first dry assemble all these parts onto a piece of .046" dia. x1-1/2" music wire (provided for the axles) as shown. Then, while holding everything snuggly together put a small drop of thin CA glue into each joint. Don't get any glue on the wire! When dry, you can take the wire out and put a little more glue on the joints if they need it.

Note: After finishing the gluing, you may find that the center hole has become clogged with excess glue and the axle wire won't fit in the hole anymore. If so, drill out the hole with a .046" dia. (3/64" or #56) drill bit. Make sure the wheels will spin freely on the axle wires.





29.

Glue the 1/32" balsa WSP wheel spokes in place on each side of the wheel. Again use thin CA and a fine applicator tip to keep the glue application to a minimum.

30.

If you want to paint your wheels, do it now (refer to the section on PAINT).

31.

Complete the wheels by gluing a piece of surgical tubing around the outside to serve as the tire. Again, use thin CA and a fine applicator to keep the glue application under control. Start by tack gluing one end of the tubing in place in the groove with a single drop of glue. Now work your way slowly around the perimeter of the wheel, lightly gluing the tubing in the groove as you go. It's not necessary to stretch the tubing as you put it on, simply make sure you are keeping it straight and not weaving side to side. When you get to the last 1" or so, stop gluing. Carefully measure and cut off the unglued end of the tubing to proper length to mate up with the first end. Prepare a small "splice" to go inside the two ends of the tubing. A balsa stick approximately 1/16" square x1/4" long should be about right. Cut it from a piece of scrap 1/16" laser-cut balsa sheet. Glue it halfway inside one end to the tubing, and then join the other end up to it. Holding everything in position, finish gluing the end of the tire to the wooden wheel.

32.

The Deperdussin's main landing gear struts are made of a plywood and balsa lamination. Locate the plywood core LG1 and balsa parts LG2, LG3, LG4, and LG5.

a.

Start by tack gluing a balsa LG2 on one side of LG1, being careful to line up all the edges carefully. Use only two or three spots of glue along the part to hold it in position. Make sure you keep the assembly flat.
Don't create a bow or twist in the assembly by gluing the parts together in mid air. Work on a flat surface while gluing.

b.

Then tack glue parts LG3, LG4, and LG5 in place on the same side of LG1.


c.

Now tack glue LG2, LG3, LG4, and LG5 parts on the other side of LG1.

d.

Now that all the parts are laminated together, flow thin CA glue liberally along all the joints and edges to make sure everything is adaquetly glued together. Let dry.

e.

When dry, block sand all the edges of the skid assembly to clean up any rough spots.

Note: Old photos show that the landing gear struts on most original Deperdussins had just slightly rounded corners, not airfoil shaped as you might think they would be. Remember, this was just 7 years after the Wright brothers first flew! Streamlining was not a big consideration at the slow speeds these airplanes flew.

f.

Repeat the process to make the second main landing gear strut assembly.

33a.

Cut two pieces of bamboo 3-3/8" long for the bamboo landing gear mounts.

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33b. Make four holes through the fuselage sides for the bamboo landing gear mounts, using the holes already in the FD1 and FD2 doublers inside the fuselage as your guide. We suggest first poking a pin through the side sheeting from the inside hole to mark the location, and then using a sharp hobby knife to enlarge the hole to final shape.

c.

Glue the two bamboo landing gear mounts in the fuselage, being careful to have an equal amount of bamboo sticking out each side of the fuselage.

34.

With the fuselage upside down on your bench, dry fit the main landing gear to the fuselage. Do not glue yet.

a.

Install the laminated main landing gear struts on the bamboo landing gear mounts. Do not glue at this time!

b.

Slide the 1/4" dia. x7-1/4" balsa dowel spreader bar through the holes in the landing gear struts. Carefully spread the landing gear struts apart until they are approximately 3/8" from the ends of the spreader bar. Do not glue at this time!

c.

Cut two 1/8" sq. balsa sticks 6-1/4" long for landing gear cross bars. Note: These two cross bars are not shown on the front or side views of the plans, because they could not be clearly shown. Study the next photo to see where they go -- one at the rear corner of the landing gear framework, and one at the front.

d.

Bevel the ends of the 1/8" sq. balsa cross bars slightly to match the angle of the landing gear struts. Place the cross bars in the landing gear assembly, using the tension of the side struts to hold them in position.



e.

Double check the final fit and alignment of the entire main landing gear assembly. When satisfied with the alignment, glue all the parts together.

35a.

Drill a .046" dia. hole in the center of each end of the balsa spreader bar. Make the holes about 15/16" deep. Press a .046" dia. x1-1/2" straight music wire axle into each hole. Leave about 9/16" of the axle wire sticking out of the end of the spreader. Make sure the axle comes out straight and parallel to the spreader. Then flow Thin CA glue around the wire. It will soak into the balsa spreader, gluing the wire permanently in place.

b.

Dacron thread is provided for wrapping around both ends of the balsa spreader bar to make it stronger. Wrap the thread tight and close together. Soak the thread wrap with Thin CA glue and then quickly wipe dry with a rag.

36.

Place the wheels on the axles and double check that they rotate freely. Then press the 1/32" laser-cut plywood WRT wheel retainers onto the axles. Slide WRT up tight against the wheel, and then back it off about 1/32" so the wheel can turn freely. Put a drop of Medium or Thick CA glue, or epoxy glue, on the outside of WRT to hold it on the axle.

37.

Cut away the covering material at the bottom rear of the fuselage to open the holes where the tail skid is to be mounted. Glue the tail skid in place.



.

WING CONSTRUCTION

38.

Two 1/4" dia. x30" balsa dowels are provided for making the wing leading edges, and two 1/4" dia. x24" balsa dowels are provided the trailing edges. Notice that each dowel has a 6-1/8" long slot in one end. Glue a 1/32" plywood WSF wing stiffener in each slot with thin CA. Make sure the edges of the WSF plywood do not protrude outside the diameter of the dowel.

When dry, sand very lightly to smooth out any rough spots. Then trial fit the stiffened end of the dowel inside one of the 1/4" id aluminum wing mount tubes. If the dowel is too big, gradually sand it down until it fits properly. You want the wing dowel to fit inside the aluminum tube with a little bit of friction, but not too much.


The idea is to achieve a snug fit that will hold the dowel in place, yet allow the dowel to be easily removed when you want to take the wings off your airplane. Obviously, you don't want it so loose that the dowel falls out.

39.

Cut both of the 30" long balsa leading edge dowels to exactly 24-1/2" long, taking the excess length off the tip end of the dowel, not the end with the WSF plywood insert. Save the leftover piece of balsa dowel to be used later as a sanding tool.

40a.

Pin the plan for the right wing panel to your building board. Cover the plan with wax paper or plastic wrap to keep glue from sticking parts to the plan.

b.

Pin one of the 1/4" dia. x 24-1/2" balsa leading edge dowels in position on the wing plan. Make sure the plywood reinforced end of the Leading Edge is at the root end of the wing panel and that the plywood insert is vertical, as shown on the plan, to provide max. strength.



NOTE: It's best not to push pins through the leading and trailing edges - they may split. Instead, straddle all narrow parts with crossed pins pushed into the building board, as shown here.

c.

Now pin the 24" long balsa dowel trailing edge and all the wing ribs (W1 thru W7) in position on the plan. Double check to see that you have the plywood reinforcements in the root ends of the dowels situated vertically for maximum strength. After these parts are securely pinned in place, glue all the joints with thin CA.

41.

Glue in balsa wing gussets WG1, WG2, WG3, and WG4 in the four corners of the wing panel. Be sure to carefully identify each gusset, as each one is a different shape.

42.

Install a 1/16"x1/4" balsa rib stiffner along the inside of the W1 wing rib. Start by first cutting the the balsa stick to length, then taper the ends as necessary for a good fit, and then carefully glue it in place. It should be flush with the top edge of the rib. (Note: The very first printing of plans called for 1/32" rib stiffner - that is a typo - it should be 1/16").

43a.

Tip rib W8 requires some fitting where each end meets the leading and trailing edges. Take a piece of the leftover 1/4" dia. balsa dowel (Step 39) and wrap a piece of 220-300 grit sandpaper around it. Use this to sand a semi-circle shape into both ends of rib W8. Hold the sanding dowel at an angle that duplicates the angles of the leading and trailing edges.



Sand carefully and keep trial fitting W8 in place in the wing repeatedly until you have achieved a satisfactory fit.

.

Note the proper position of W8 from the photos - the outer edge of W8 should be tipped outward to achieve the full wingspan shown on the plan, and the top of W8 should be slightly lower than the rest of the ribs (notice the gap between W8 and the ruler laying on top of the other ribs).

b.

When satisfied with the fit of W8, glue it in place. When dry, use a fine grit sanding block to sand off the excess leading and trailing edges until they are flush with the wingtip rib.

c.

Cut to length and glue in position the 1/8" sq. balsa wingtip braces.

44.

When dry, the entire wing can be removed from the building board. Double check all the joints for adequate glue and apply a little more if necessary. Let dry. Then carefully clean up any rough edges and glue joints with the sanding block.

Repeat Steps 40 through 44 to construct the opposite wing panel.

45.

Lay the wing panels back on the plan and use a 90 deg. triangle to mark the locations of the 1/16" od x1/4" Aluminum Tube Rigging Points (4 per wing panel) onto the outboard faces of wing ribs W4 and W7. Glue the rigging points to the ribs at those locations. Be careful not to get any glue inside the tubes.


46.

Use a sharp #11 hobby knife to make 3/8" dia. holes in the fuselage side sheeting where the trailing edges of the wings will be mounted. Make sure the bottom of the hole is flush with the top of the rear dihedral brace RDB.

Tip: Before starting the hole, locate the top edge of RDB precisely on the outside of the fuselage by pushing a pin thru the side sheeting from the inside. Then mark and cut the 3/8" dia. hole from that point. Due to the fragile nature of the side sheeting, it's best to make the hole undersize first, and then gradually open it up closer to finished size. Finish shaping and sizing the hole with sandpaper wrapped around a scap of 1/4" dowel.

47.

Sand the outside of the four 1/4" id x1" Aluminum Wing Mount Tubes with 220 grit sandpaper to improve glue adhesion.

Then slip the wing mount tubes onto the root ends of the leading and trailing edges of both wing panels.

Now trial fit one of the wing panels to the fuselage, resting the wing mount tubes in position against the FDB and RDB dihedral braces in the fuselage. When you have the wing panel lined up properly, have a helper put a single drop of thin CA glue between the aluminum tube and dihedral brace.


Don't over glue at this point or the excess glue might seep inside the tube, permanently gluing your wing panel into the tubes. After tack gluing both the front and rear tubes to the dihedral braces, have your helper slowly pull the wing out of the tubes, while you continue to hold pressure against the tubes, keeping them from breaking loose.

After the wing is removed, reglue the wing mount tubes securely to the surrounding fuselage structure with medium or slow CA. Avoid getting any glue inside the aluminum tubes.

48.

After one set of wing mount tubes has been installed, repeat the same procedure to install the wing mount tubes for the opposite wing panel.

Set the wings aside until needed later.

.

TAIL SURFACES

48.

Cover the Stabilizer/Elevator plan with wax paper or plastic wrap for protection. Use 1/8" square balsa sticks and laser-cut parts S1 and S2 to construct the Stabilizer directly over the drawing.

Note: Remember to cut the longest pieces of 1/8" sq. balsa first, then the shorter pieces, in order to make the most efficient use of the stock 36" long sticks.


49. Use 1/8" square balsa sticks and laser-cut part S3 to construct the Elevator directly over the drawing.

When dry, unpin both the Stabilizer and Elevator from the plan and lightly sand all the glue joints smooth.

50.

Cover the Fin/Rudder plan with wax paper or plastic wrap for protection. Use 1/8" square balsa sticks to construct the Fin directly over the drawing.

When dry, unpin the Fin from the plan and lightly sand all the glue joints smooth.


51.

Use 1/8" square balsa sticks and laser-cut part CHN to construct the Rudder directly over the drawing. When dry, unpin the Rudder from the plan and lightly sand all the glue joints smooth.