Description and Assembly
The P1 is a single prop, high wing, hotline style RC plane for 3D printing. Its a fast plane with relatively high wing loading, for intermediate and advanced pilots.
Its small scale means it can be transported fully assembled.
P1 Parts list
Whatever you do, DON’T skip ahead in the instructions or glue pieces together early. This could result in you having to re-print a part.
You will need:
1.2mm piano wire for control rods and hinges.
CA “super glue”.
Hot melt glue.
M5 Hex nut (for attaching prop spinner to shaft.)
Velcro to secure LIPO.
5 small screws with washers. I use the excess screws from servo pack
Good Quality PLA Filament. https://amzn.to/2OqjUUZ
Radio Equipment and Electronics
2-3 9g servos . https://amzn.to/395JIxp
Receiver and Transmitter.
1300maH Lipo. https://amzn.to/2UnfUIB
T2836/08 Brushless Motor (or similar). http://www.modelshopleeds.co.uk/catalog/product_info.php?products_id=24581
20A ESC. https://amzn.to/36ZElyq
Suggested slicer settings
Its best to build the P1 using these instructions with the build video below expanding on some parts.
Measure and cut your piano wire for the ruddervator hinges. Dry assemble each fin to make sure the wire is the correct length and won’t cause you trouble when glueing. The control horn should face DOWN. With the control surface in place, glue each fin onto the tail, checking that the elevator is free to move.
Glue the tail to the middle section. Before glueing any surface together its a good idea to gently sand the joining areas. Once this is set you can put it to the side.
Wings. The control rods are integral to the wings. Start off by dry assembling the left hand wing with the piano wire running through the aileron and the aileron end cap. With everything dry assembled make sure the piano wire is pushed as far as it can go into the outboard section of the wing. Make a mark on the piano wire at the point where the aileron and the aileron end cap meet. Disassemble the wing and make another mark about 3mm outboard from the first. This is where you need to put a U bend into the wire as shown.
Reassemble the wing with the U bend inserted into the slot on the aileron and make sure nothing it goes back together. Now glue the aileron and the aileron end cap together with the piano wire ben in the slot. With the aileron now firmly glued, assemble the wing with about 1/2 an ice lolly stick in the joining slot and glue the inboard and outboard section of the wing together.
Lay the wing upside down flat so that the aileron is in its neutral position, then make a 90 degree upward bend in the piano wire at the wing root. Try to keep the bend close to the hole. You can clip the wire about 5cm from the bend.
Do the same with the right hand wing.
Joining the wings
Place each wing into the wing/fuselage bracket, if placed in at an angle you should be able to get the piano wire in too. The slot in the wing will take a full 60cm ice lolly stick but if your having trouble getting it all in use about 2\3 and slide it deeper into the first wing so as to make space to insert it into the second wing.
Carefully and accurately glue the wings together. Once set, you can place some glue into he underside of the wing/fuselage bracket and wing join, capillary action ‘sucks’ the glue into the join.
Fix your servo into the gap made at the join of the wings. I tends to use hot glue for this, you probably want o keep the temperature down a bit (around 160C) if you can. You can now connect up the controls as shown.
Use epoxy to attach the aileron control linkages to the piano wire sticking out of the wing. Again it's a good idea to dry fit it all together first.
Fix your motor on to the firewall. Dry fit the firewall and motor into the nose to check it fits, its a good idea to sand the area where you the firewall will sit. If your motor is a different size you may need to use some spacers.
There is a cutout on the back of the firewall to allow the canopy bracket in, make sure this cutout is at the top.
Once you’re happy it fits, have a few practices at getting it into place quickly before you do it with glue.
Dry fit the elevator servo mount. You want to make sure it is placed such that it doesn’t conflict with the aileron controls. Before gluing the elevator servo in place fit the piano wire control rods and attach them to the elevator. Glue in the servo mount. With the control rods attached use hot glue to affix the servo in the mount.
If you want to use 2 servos to have a 'ruddervator' you can install a second servo in tandem. Sit it at a different angle so that the piano wire doesn't interfere with each other.
In preparation for fixing the wing/fuselage bracket, use a drill to widen the holes in the side of the wing/fuselage bracket slightly. Fit the wing bracket in place and add your screws. There is no need to screw them in too tightly or you will break the skin.
Fit your canopy onto the cockpit by placing the lip at the front under the skin and sliding forward. When in place carefully drill a small hole at the back where it will be fitted. Mark the position on the fuselage and drill a small hole there too. Now you can fix the canopy in place with a screw.
The prop spinner needs a M5 hex nut. Place this into the gap with some glue, leave it to cure before attaching to the shaft. Once cured, screw on the spinner with the prop in place, for this reason you need to use a clockwise spinner propeller, as otherwise it is difficult to get it tight and it will work itself loose.
You can wire up your electronics and fit the wing to the body using 4 screws.
Prepare for Flying
Common to most RC planes, the centre of gravity should be between 1-3cm from the leading edge.
This is an intermediate to advance flyer. The small scale of the plane means that at 600g it has a fairly high wing loading. This means it flies fast. Couple this with the relatively short wings and it makes it susceptible to torque roll at low speeds, especially when hand launching.