Using RC components with Lego

[finhudson]

I recently built a Lego boat using a non-lego electric system. I instead used a brushless motor and ESC, a servo, a receiver and a 3S lipo battery. I also designed and 3D printed a better, bigger propellor than anything lego has to offer. More details in the video:

I managed to find a motor and servo with mounting holes that are the right distance apart to use with lego, and I used a reasonable slow motor (1000kv), as not to cause excessive wear to the lego parts. I didn't pay any real attention to the looks of this model, it was just made to be fun to sail.

It came out so much more fun to sail than any boat I have ever made with the Lego PF or RC system.

Have you guys ever built something using non-lego parts, and if so (or if not), what do you think of it?

Edited April 4, 2016 by finhudson

[nerdsforprez]

I have built several projects with Lego and RC. You will hear some flak from others because of the lack of sense combining the two..... and I have to agree with them on that point because they really are not that compatible. Except for one factor.... and that it is just (IMO, and probably yours as well ) darn fun. You creation looks fun.... and bold. A brushless motor? Good idea to go with something fairly slow.... even though you found a way past Lego limitations on propellers I would have thought a brushless system would ruin the whole drive train. Did you use lubrication? That will help a little with the excessive wear.

Although your build looks fun to drive your model 2.0 will be best served looking at how the hull can reduce the drag. Your design looks like there is lots of it and improved hull design will probably really release its speed.

Fun post..... thanks for sharing.

[aol000xw]

I love this kind of MOCs

I see no reason against combining RC and Lego. RC can easily break Lego, true, ABS have its limits after all, but it's just a matter of taking those into account when building and enjoy the range and power of RC.

PF is way below what Lego can handle, even if a stupidly down-geared XL motor can snap gears. Just keep this at hand...

...and enjoy some RPMs

[finhudson]

Glad to hear some others loving combining RC an lego too!

your model 2.0 will be best served looking at how the hull can reduce the drag.

I completely agree, after sailing it, it became very obvious that it was too heavy and had too much drag, but it didn't make it any less fun.

I didn't need any grease to avoid excessive wear, but then I'd designed the drivetrain so that there were only 3 points of contact between the spinning axle and other parts. It handled the brushless power surprisingly well. It could be to do with the entire drivetrain being submerged in water for the whole time.

PF is way below what Lego can handle, even if a stupidly down-geared XL motor can snap gears. Just keep this at hand...

...and enjoy some RPMs

I totally agree about PF being way weaker than what lego can handle, the lego RC system was better, but just too heavy.

Good idea with the grease, I'll probably try that for the version 2.

One other point to make is how much smaller and lighter the brushless motors are than lego motors. The small one I used on this boat is equivalent to more than 10 RC buggy motors at full throttle.

Edited April 4, 2016 by finhudson