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The Sail-Cam Project

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       The non-powered Easy Glider kit was designed with a launch hook to be glued into the bottom of the glider. This is so the model can be launched with a “Hi-Start” Bungee launch system. Since my glider will be propeller powered I will not need the Hi-Start hook. I decided to use the hook mounting location for a wheel pocket which will hold a Du-Bro 1-3/4” Super Lite wheel (#175SL). This wheel will help protect the bottom of the glider during landing as well as the FS8 pitch/roll sensor that will be mounted behind it.

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       I used my Stanley knife to cut out two half moons where the wheel will be mounted. I left an 1/8” gap on both sides of the wheel and all around the radius. This location is perfect for the wheel as it is an inch or so in front of the CG which will provide just enough tail weight for it to land correctly. Notice that the pocket just barely touches the battery slot.

       The next step was to make a bay for the FS8 receiver. I decided to install the receiver under the wing saddle to provide more space in the nose of the plane. This location will also keep some physical distance from the future video transmitting equipment in the nose. The video transmitter puts out a 1/2 watt of power which can cause problems with some electronics in close proximity.
       I cut a slot out that was just wide enough for the receiver and a little longer to allow for connection of the servos. Notice the slot on the bottom of the cutout, this will be used to install the antenna in the future antenna tube.

       I installed the linkage tubes as well as the antenna tube into the fuselage as the manufacturer suggested. The only change was that I turned the antenna tube up into the receiver bay instead of the front.

       The next step was to build the motor pylon that will support the Ultrafly brushless motor. Using some cardboard I cut out a template that will make up the motor support bracket. This bracket will bolt the motor to a pylon tube that will hold it above the fuselage. Notice that the bracket straddles the exposed motor shaft, this was done for aesthetics only. I cut the bracket out of some scrap aluminum and formed it like my test pattern template.

       I used some K&S Engineering aluminum tubing for my pylon support tube. Notice the aerodynamic “teardrop” profile of the tubing, not necessary but a nice touch. I bolted the bracket to the tube using a small through bolt.

       I left a small amount of play in the pivot of the bracket so my thrust angle can later be adjusted. This is important as the plane will not fly correctly if the thrust angle is not correct. A small hole was drilled into the side of the tube to allow for the motor wires to be run down the pylon tube. Once again, not necessary but looks very clean.

       The next step was to modify the 7 x 4 APC Slow Flier prop to fit the Ultrafly motor in “pusher” mode. The APC prop normally comes with a “stepped” hole for mounting where the big hole side is use to mount to a brushless motor with a rubber band  mounting system. Since I will be using the APC prop as a pusher, I will need to drill out the mounting hole to allow the hub of the Ultrafly motor to fit. I used a 7/16” drill to ream the prop out.
       I installed the factory prop mount screws into the motor and used a couple of O-rings as rubber bands to hold the prop in place.

       I now had to make the decision on where to mount the pylon as this will effect the planes CG greatly. I “installed” a majority of the parts in the fuselage and taped it together temporarily. The tail section and the wings were also temporarily taped on to the fuselage. I then balanced the plane moving the motor back and fourth till the pane was somewhat balanced. What I came up with was to mount the motor about 5” behind the trailing edge of the wing.
       A slight groove was cut out of the foam to allow for the installation of the motor pylon in each fuselage halve. The pylon was then cut to length to just clear the propeller over the fuselage. A pocket for the Apollo 12 speed control was made just in front of the pylon as well. I made this pocket kind of snug so the speed control will not come loose.
       Some 22 gauge wire was soldered onto the motor leads to extend them through the motor pylon. Then 3.5 mm bullet connectors were soldered onto the motor leads allowing them to be connected to the speed control. The power lead of the speed control was also extended to reach the battery connector up front. I used 18 gauge wire for the power lead, solder and shrink-wrap was used for the connections.
       Sandpaper was used to roughen up the lower part of the motor pylon and then thick CA was used to bond it to the fuselage half.       

       A small groove was cut into the inside face of the fuselage to accommodate the power wires. The 18 gauge wires were then glued into the groove for added strength and so they do not move while glueing the two fuselage halves together. A small groove was also cut out for the servo lead of the speed control towards the bottom rear of the wing saddle. This is to allow the lead to be removed if necessary once the fuselage is glued. Notice the antenna tube as it is turned up in the receiver bay.

 

       High-temp hot glue was used to secure the HS-81 servos into the fuselage halves. This way they can be removed later for repair/replacement. Hot glue can be very useful when working with foam models as it is very easy to use and holds foam very well.

       The next step was to prepare the nose of the aircraft for the camera port. This will be the hole that my PC75WR “bullet” camera will mount in. I started out by tracing a line around the nose of the plane. I angled this cut slightly down as the camera will be mounted at about a 6 degree angle to the incidence of the wing. This will help the pilot navigate better when looking at the transmitted video image.
       I used my Stanley razor knife to cut the nose off (despite the planes good looks :0)

       I used a sanding bar to round off the sharp edges of the cut and contour the nose a bit. A hole was then cut for the bullet camera to snugly fit into.

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