Scratchbuild of a Multiplex Funjet clone


I am always looking for great scratchbuild ideas.  When I stumbled onto the channel of "Project Flight Design" and found the how to videos of making the Funjet clone, I was super interested.  Being into speed flying as of late, I have been wanting to purchase a Multiplex Funjet and mod it out for extreme speed.  However, when I found the scratchbuild idea and videos of the making of the Funjet clone out of Dollartree foamboard, this got me really excited as I love scratchbuilding and then to be able to build something very similar and close to the actual Funjet makes it even better.

The guy running ProjectFlightDesign has a couple of really great how to videos where he actually steps you through the entire process of building his Funjet clone including marking and cutting out the foam, cutting out control surfaces, mounting hardware, etc.  It is really an easy build especially with the very thorough explanations of everything.  So if you are into scratchbuilding and have also wanted to own a funjet, these videos are definitely worth checking out.  Click the hyperlink to his channel above.

Also, the beauty of scratchbuilding is that you can take designs and improve them, change them, and tailor them to your own tastes.  I essentially left the build of this plane as he shows in the how to videos except for reinforcing the foam board, installing a carbon shaft and using a SuperMegajet from Grayson as opposed to the Microjet that is shown in the videos.  I wanted to make sure that with the speed I am hoping for, the structure of the plane will withstand the forces exerted on the plane.

Parts Used

  • Dollartree foamboard - 2 sheets
  • 1/2 Home Depot Pink Insulation foam
  • Clear Packing tape
  • Grayson Hobby SuperMegaJet w/50 Amp ESC
  • 6x4 inch prop
  • 2 Hextronik 9 gram servos
  • Colored tape for orientation

Pics of my build

  • After getting the shape of the main structure cut out and the KFm-4 airfoil glued in place




  • Here you see the channel I cut for the carbon rod to go in


  • The main structure of the plane takes shape after gluing in the tail fins and laying out the electronics on the body


  • A close up pic after attaching the SuperMegaJet from Grayson and laying out the 50-amp ESC as well




  • This is a shot of the control surface, pushrod, and servo that I am using.  At this stage nothing was glued in place, just had cut out slot for control surface arm and servo and laid them in.



I have yet to maiden this badboy, but I will post some flight footage as soon as I can get it up in the air.  I still have some gluing to do and some strengthening I would like to add to the body of the plane just to make things even more rigid.  I have a feeling this thing is going to be a beast in the air and take the number one spot in my fleet as my fastest plane.  We will see!  I will keep you guys posted on the progress of this build so check back often and please add your comments in the comments section below.