R/C Helicopter project


Here we have the fuel tank nipple. This is a push in design that is held by a web in the middle, similar to the ones on each end that hold the fuel line on.


Now that the bulk of the work is done on the main portion of the helicopter I imported all the updated parts into Fusion 360and prepared a few renderings to share with everyone.

Next up is to start modeling the tail gear box, tail boom and tail rotor assembly.




I now have the gear box modeled, as well as the approximate length of the tail boom. The parts in pink are temporary place holders as the actual gears should be there. I haven’t started the gears yet. The tail boom is keyed so that it can be located by depth as well as prevent rotation.

As before these parts could change as the model evolves.


Are you just interested in doing these for hobby or you plan to do some sort of businesses out of?!


Right now I am just doing these for fun/hobby. I am new to CAD and just teaching my self how to model things that interest me.

So what I am doing is picking mechanical things of interest and modeling them. I hope to someday do this type of CAD professionally. But I have lots to learn.

At this time I have no interest or plans to manufacture anything. This is purely for training myself.


Actually, the stuff is very good if you’ve not been trained anywhere to date!

Best of luck !


Thank you. I have no training to date other than YouTube videos and hundreds of hours on Shapr3D. I have a decent amount of time on Fusion 360 now too. But that is just with importing models, lining up parts, adding threads and rendering.

Many years ago I gave SolidWorks a try, my best creation was a solid cube, I couldn’t grasp how to do anything. I gave up as formal training wasn’t an option back then. Then just over 1 year ago I found Shapr3D and tried it on my girlfriends iPad Pro, I believe February of 2017 is when I started. Within a few hours I was able to create simple things. I ordered a first gen iPad Pro 12.9” and subscribed to Shapr3D. My first creation is the Hexabot that I shared here in the forums.

I took a break from it for about 11 months playing with Fusion 360 to learn the basics. I spent most of my time riding my Harley. Then with the erase of the gen 3 iPad Pro I decided that I would give it another go. And in short, I am addicted to it now.

Thank you for the compliment and advice, I appreciate both.


Yes I also believe Shapr3D revolutionized 3d-modeling. And of course, 3d modeling should not be a sophisticated process, to solve equations for! Many of physical problems were not simulated (or even maybe now), just because of the complicatedness of their geometry. Easy 3d-modeling = more innovations on every side and size

Wish you best luck.


Here is another screenshot of the tail gear box in its approximate place on the helicopter.


Here we have some bevel gears added. I am still very new to modeling gears and I know there are equations to creating bevel gears. However, for my purpose here, I just want them to look visually good. They may not be accurate to what would be used in real life, but accurate enough for the models representation.

So after much trial and error, I figured out how to get the angles needed by using the project tool. Once figured out, it made easy work of getting the look needed. Then I was able to use the scale feature to get them visually the matching size to the model. Here are a few screenshots of the results.

The bottom two screen shots show the sketches I used with the project feature. It’s a crazy mess of lines. But it worked. I’m sure there’s a better way. But once I got started it made sense to me.

I’m not happy with the other gear, and will likely rework it at some point.


Here we have the drive shaft for the tail rotor modeled and in place. Still need a couple support bearings in the tube.


Here we have the gears positioned now.


Here we have some work on the tail boom supports and the control rod. There are now 507 parts to this model. And if I had to guess, I would say I have about 100 to go.


Here we have the boom support clamp and horizontal tail fin. The fin is non functional and there for aesthetics only. The boom supports are now in their approximate location as well.


Here we have a quick render of the model up till now. This was done on my Mac which is no where near as powerful as the custom PC I typically use for the Renders. But I wanted to show a quick look at what it should look like. When I get further along I will do a high quality render.


How do you calculate the angle of the gear teeth to ensure they link properly with the other gears? Is this a complicated mechanical engineering math equation, or is there a practical way to sketch it out while modelling?


It is a calculated equation. In my models the gears are purely for visual reference, so they may or may not be accurate. Only thing accurate for sure is the spacing for each tooth. I decide how many teeth are needed to achieve a certain head-speed (main rotor speed), you need to know the motor specs as well and the pinion size that will be used. Once you know the tooth count you can divide 360 degrees by the tooth count to get the angle needed to get the exact amount of teeth. Then from there I just manually sketch out a tooth. If this were a real R/C Machine I would be able to calculate all this as I have more than 14 years experience with them.

In the link below there are some details on how to do it if this were to be real.



Here are a couple better renders. This is of all work that I completed so far on this model.


Here we have the control arm modeled and in its position. This controls the mechanism that will change the tail rotors pitch.