Broken Lift Efoil


#41

Does anyone know if the lift foil uses a out runner?


#42

No one knows exactly what they use at this stage. But I suspect they designed an inrunner that uses the entire motor pod. The size of the pod makes it unlikely to be an outrunner.


#43

I bet your right.

A purpose built stretched SS motor, low KV, with thrust bearing, seal, shaft, and outside tube, all in one neat package.

I suspect it won’t be long until people will be able to purchase replacement parts.


#44

Unfortunately I have heard the same from others and also that the Lift batteries seem to run hot, which is not a good thing to hear. Based on my somewhat limited knowledge for batteries, fast charging like Lifts 20A is very hard on them. It shortens the amount of life cycles and makes the cell unstable. 10A charger is the max before you start doing long-term damaging for big batteries like these. If that is the case then it’s just a matter of time before house or yacht has a fire when an unstable battery bursts into flame.


#45

Where did you get the info that it’s direct drive ?


#46

As a matter of interest where did you hear the 10A thing. Normally for li-ion you charge between 0.5C - 1C. Therefore for a 42Ah (Lift spec) battery, 20A charge would be just below the 0.5C.


#47

They mentioned it in a video where they tested it in Slovenia, they said it is silent because there is no noise from the gear: Testing all Electric Hydrofoils and making videos (Jetboard testing tour)
7:21


#48

Lift foils told me it is direct drive, that is the most direct answer :slight_smile:


#49

Why we have no single approach here in the forum for a working direct drive inrunner setup like Lift has?


#50

Probably because almost no one here bothers DIYing or customizing motors. And you will need a highly custom motor for that, there is nothing close in the RC industry.


#51

Couple close-up pics of Lift drive pod…


#52

I’m not sure I believe their efoil is direct, but who knows, maybe they have a super strong $5000 inrunner inside. :wink:

Some of us do have direct drive units here and they work amazingly well Superlefax. there are jet propulsion/direct drive threads on the forum here.

But really, if you use a 3:1, 4:1, 5:1 etc… reduction drive, you should get away with a really short motor and have all the torque you need. 56mm inrunner is good, but there is no need for 104mm, 114mm, or 122mm length, its overkill for torque based on what I see everyone is building here in the forum.

Some of the builds here are smaller diameter motors to match that of the reduction gear which I think is great. its less money, less weight, and you reduce parasite drag.


#53

That’s why I have used a 96mm length motor and it results in a drive unit at least 10cm shorter than the standard PM build ones.


#54

Does drive unit length matter?


#55

The shorter it is, the less strain on the mast clamp. I think it looks a bit neater.


#56

Not really as Jezza mentioned, but the diameter does


#57

I would say yes length of the unit does matter.
As mentioned the longer the unit the higher the strain on the clamp.
it is also important to consider the higher loads acting on the pod when you are doing aggressive turns.

just consider having a 1m long propulsion unit with a prop guard making a tight turn. in this configuration, the draggy prop-guard and the pod itself needs to move sideways through the water at a much higher speed than with a shorter unit.


#58

Looks like a manufacturing error. The design looks thick enough.


#59

There’s a new inrunner at Alien the 56200, could it be the same Lift is using? Anyone, tried it?


#60

Good find. Do you see the picture?