R/C hovercraft with parts that can be printed easily, and mostly without supports. 

The hovercraft will require some basic assembly work. Below, you'll find the list of parts required, as well as some assembly instructions and some explanations on how I created the skirt from a plastic bag.

Short video: 

Parts required (Bill of Material):

• Electronics:
  • Any radio system with 3+ channel R/C receiver
    • One channel for the hover fan (on a rotary knob, 3 position switch or slider)
    • One channel for the propulsion fan (throttle channel)
    • One channel for the rudder servo (steering or aileron channel)
  • Two 1106 (4200 kV) brushless motors + screws (1104 and even lower kV should also work)
  • Two 3016 propellers (GemFan)
  • Two 10A brushless ESC (I used super cheap (obsolete but good enough) SimonK ESC's)
  • One 9g servo
  • One XT30 (male) connector
  • One small 2S or 3S Lipo (400-500mAh will do the job) with XT30 connector
• Other (mostly junk you probably already have):
  • Some heat shrink or (electical) tape
  • Some self-adhesive velcro to attach the battery to the top of the craft
  • Tapes: 
    • Thin double sided tape to attach the skirt to the skirt's skeleton
    • Thick double sided tape to attach the components to the chassis
    • Painter's tape
  • A plastic bag (I used a polyethylene freezer bag that my wife was kind enough to donate) for the hovercraft skirt
  • Glue (hot glue is easiest)
  • Some cardboard / wood / coroplast to make the rudder
  • Material to create the linkage from your servo to the rudder and between the rudders if a triple rudder is used (I used some basic metal wire)

Printing:

• Choose “propeller” or “triple rudder propeller”. 
  The triple rudder propeller is recommended. It gives way more control authority... 
  • If the “propeller” part is chosen, the “rudder” part is needed once. 
  • If the “triple rudder propeller” is chosen, the “rudder” part must be printed 5 times.
• Only the “hover fan” part requires support. All other parts can be printed without any support.  I used PLA and default settings.
• Brim is recommended to prevent that parts detach from the print bed.

Tools required:

• Hot glue and superglue to assemble the different parts
• Soldering equipment
• Optionally a covering film iron

Some tips on the assembly:

• The "rudderHolder" part:
  • If the “propeller” part is chosen, the “rudder” part is glued on top of the “propeller” 
  • If the “triple rudder propeller” is chosen, three “rudder” parts should be glued on top, two in the slots on the bottom. 
• You need to cut the actual rudder from some cardboard or plastic and add a servo horn to it. I used "coroplast" plastic sheet I had lying around.
• You need two ESCs in this project. I joined the power leads of both ESCs and soldered the XT30 to both of them.
• If you use the SimonK ESCs, they have a built-in BEC, which supplies voltage to the receiver and the servo. It is generally recommended to only plug in one of the BECs into the radio receiver. To do this, choose the servo plug (the one going into the radio) of one of the ESCs and cut its red wire (or remove it from the plug and isolate it with tape.
• When mounting the motors, there is a cutout foreseen for the motor wires. Use the cutout to avoid pinching the motor cables.
• The servo:
  • Is supposed to be glued in from the bottom 
  • The control linkage to the rudder(s):
    • Single rudder: there is a space under the propeller where you can guide your control linkage.
    • Triple rudder: control linkage goes on the port side (it's a ship, you know) of the propellor, and should attach to the leftmost of the three rudders. Link the two others to this rudder with some steel wire (see photo).  
• For the skirt, the method I used involves first attaching the skirt support to a bag, and then welding the bag to size: 
  • Attaching the bag:
    • Put the bag as flat as possible on a table. 
    • Take the skirt support and put it in the bag. Center it in the bag as best as possible. 
    • Mark the outer rim of the skirt support on one side of the bag, and mark the inner rim of the skirt support on the other side of the bag.
    • Now it's time to attach the bag to the skirt support, in line with the markings. 
      I used thin double sided tape for this. This is a fiddly job, be patient :-)
    • Cut the right holes in the bag (try not to perforate parts that should not be cut): 
      • on the side attached to the inner rim, the interior of the inner rim should be cut out.
      • on the side attached to the outer rim, the interior of the outer rim should be cut out. 
  • Welding the bag to size:
    • Then use a marker to draw a line on the top of the bag that is a few cm (I used 5cm, 4cm is probably better) away from the outside border of the skirt support. Note that near the rear corner of the craft, this means that you'll end up with two quarter circles.
    • Put painter's tape along outer side of the line drawn in this way. The goal of this tape is to prevent the polyethylene from shrinking while we weld it.
    • Put the bag perfectly flat on a wooden plank or something that can cope with heat of the welding.
    • Use a film covering iron or a soldering iron on 150° C and heat up the painter's tape along with the two layers of polyethylene. Avoid direct contact with the polyethylene (it will shrink); only heat up the painter's tape. Do this along the entire edge of the skirt. 
    • When you're done, leave a little rim of painter's tape and cut away the excess with a knife or scissors. 

As always, have fun!

If you liked the model, please leave a like and/or a make. 

Let me know if you see opportunities for improvement.

PS: yes, I drew this after looking into the popular model of Sir_Lancelot178 ( [https://www.printables.com/model/333283-simple-brushless-rc-sport-hovercraft](https://www.printables.com/model/333283-simple-brushless-rc-sport-hovercraft) ), but I wanted something that would fit on a 210mm build plate and that I thought would be a bit easier to print.