How To Build FT Toothless

Greetings Aviators!

Recently I posted an article about a plane I had built. His name was Toothless and he was the first RC plane that I personally designed. I originally wrote the article just for fun and I didn't expect much to come out of it. However, Flite Test was kind enough to share my article and get it out there for more people to see. And let me tell you, the response was incredible!

I was amazed by how many people liked, shared, and commented on my article! So first I would just like to say thank you! Thank you very much! Your positive responses motivated me to continue with this project.

Through this process, I had multiple requests for plans on how to build Toothless. So here you go!

FT Toothless - Full Size Plans

And, just for fun, I made a video explaining the build process. So here you go again!

Just a general FYI about this build: You need a Power Pack C (available on the Flite Test store), about 3.5 sheets of foam board, and two servos, along with all of your regular scratch build supplies.

Now lets get into the details.

Once you've cut out all of the parts, the first step is to make the wings. If you have ever made the wings for either the Simple Soarer or the Spitfire (or any other Flite Test airplane for that matter) the process is exactly the same.

Start by making a double 45 degree bevel along the leading edge of the wing. I also like to reinforce the leading edge of the wing with a strip of packing tape. This keeps it from ripping and makes it more crash-resistant.

Next, take the spar and glue it in the middle of the crease cuts on the top inside surface of the wing. Then, glue the wing spacer along the back edge of the bottom surface. Because the top surface of the wing extends so far behind the bottom, you need this spacer to make sure that the trailing edge does not extend below the bottom of the wing. 

To glue the wing together, you'll need a strip of glue along the inside of the leading edge crease, another along the bottom of the spar, and a final strip along the spacer at the back of the wing. If you don't have a glue gun that can put out glue fast enough, just do the leading edge and spar strip first and then do the spacer strip. Then fold the wing over and press it down on the top of the table while it all dries.

The second wing is made the exact same way, just mirrored. Once you have the two wings, take a little foam off the middle of the top edge of both wings to allow room for the dihedral. You want to have enough dihedral that one of your wing tips lifts up about 3 inches from the horizontal while the middles are flush.

Then put a strip of packing tape on the bottom, glue all around the inside edges, and hold the wing halves together with the dihedral. Then put another strip of packing tape over the top of the wing to give it more strength.

And there you have it! The wing is done. Next step, the tail.

For the tail, you effectively need to bevel all of the long edges along the tail spar. This allows the tail to fold up into a nice triangle.

After doing all of those bevels, just glue along each seam and put tape on the outside, this will make it plenty strong.

For the rear end of the tail, you'll notice that the sides are shorter. This is to increase the angle between the v-tail surfaces. Ideally, you want about 120 degrees between the two tail surfaces. I only learned this after I had already made the tail spar and attached the fins, so I had to do some rearranging. 

After gluing the triangle spar together, cuts a 45 degree bevel into the control surface side of the tail fins. Then glue the tail fins onto the cut out section of the spar. I like to attach them so that the beveled side faces down. Gives it a cleaner look. I would also suggest that if you are going to be doing any painting of the tail fins (for example, making one red!) do it before you glue them onto the tail.

After gluing on the tail fins, insert two bbq skewers into the foam as shown to strengthen the tail. Because we had to cut the tail up, you have to do something to strengthen it again. So add the bbq skewers and glue them down to the back of the tail.

Next is the fuselage. Basically, you need to bevel every single outside and inside edge of the fuselage except for the front and back edges of the top of the fuselage. The goal is that when you're done the fuselage need to be able to fold up into a nice trapezoid as shown in the images below.

After you've cut the bevels, only glue the side wall and the front into position. Make sure to leave the rear flaps unglued so that you can easily insert and affix the tail spar. I also like to add packing tape along the outside of every edge to make it plenty strong. I don't know if this is necessary, but I haven't yet broken an edge that was taped. 

Next, insert the tail 3 inches into the back of the fuselage and glue it down. Then close in the rear flaps of the fuselage and glue them in place. 

At this point you want to install your servos and control rods before closing in the bottom of the fuselage.

For the control rods, I used 0.055 in music wire. I put it into the second hole on the servo arm, ran it back through a coffee stirrer taped to the tale, a zip tie loop on the tail, and into a control horn on the control surface. If you are using the FT control horns, put it in the outermost hole. You can experiment with the throw levels, but I find that fairly high throw rates are desireable since you've only got the v-tail to control such a large plane.

After inserting the servos, close off the bottom of the fuselage and flip it over to attach the wing. 

To mount the wing with the dihedral, you'll need to add a couple of spacers to the outside edge of the fuselage. Attach the spacers so that the front edge of the spacers is in line with the middle of the forward power pod mount slots. There is a reference line for this point on the plans. This is also the line where you will mount the front of your wing.

The goal is to get your wing touching the fuselage at the center line and along the two spacers. You may have to squish down the foam spacers a bit depending on how the dihedral on your wing ended up. 

Once you've got the wing how you want it, put copious amounts of hot glue along the spacers and the centerline of the fuselage and stick the wing on. You can also make the wing removable by inserting bbq skewers ahead of and behind the wing, then just rubber band the wing on. I prefer the fixed wing because it makes it firmer in flight and more consistently placed. However, a removable wing is also nice because it makes it easier to transport and you can move the wing around if you need to. So, I'll leave that choice up to you.

To finish it off, just insert and affix your power pod the same way you would for any of the other swappables. Also, set your battery location (and possible add some counterweight) to place the CG right underneath the spar of the wing.Then program your transmitter to work with a v-tail and you're good to go!

Once again, thank you so much for your feedback and positive responses! You guys are the best! Feel free to make any modifications you like. I'd love to see what you come up with! Have a great day and good flying!