Weight reduction of Mini 2 down to 212g = 4 minutes more air time.

[YVRGUY]

I remember the “Old Daze” when we would take the heavy engine hoods off our 55 Chevys and 40 Fords to lighten the cars, supply more cooling, and show off the engine…why not, whatever turns your crank…cool

 

[MS Coast]

I can certainly see how a heat sink might not be needed during a winter flight in Canada.

 

[Yogi053]

-17c, I don't think I would risk mine in that temperature even with it fully 'clothed' and not naked like you did. Each to their own I suppose.

 

[slozukimc]

The heatsink probably isn’t needed with everything open like that. It get much more air now.

Now take it further and look into what GM did building the Swiss Cheese Catalina. I bet you could drop a lot of weight with a drill and careful hole placement.

As far as handling better in the wind think of it this way…..a van and a pickup can weigh the same but which one handles better in the wind?

Mike

 

[slozukimc]

Hmmmmm. I wonder if a dimpled surface like a golf ball would make it more aerodynamic?

Mike

 

[Bodkin's Best Photography]

I can certainly see how a heat sink might not be needed during a winter flight in Canada.

There's that stereotype again...

 

[Dushash]

There's that stereotype again...

No worries, heat sink is back. So I’m now at 214.7g
With some conformal fluid to make it rain/snow weather capable (to a reasonable extent) I’ll go up to 215g but will be able to fly in hot or cold just like stock Mini 2.
So to keep everything functional 215g is the lowest for now.

 

[Dushash]

The heatsink probably isn’t needed with everything open like that. It get much more air now.

Now take it further and look into what GM did building the Swiss Cheese Catalina. I bet you could drop a lot of weight with a drill and careful hole placement.

As far as handling better in the wind think of it this way…..a van and a pickup can weigh the same but which one handles better in the wind?

Mike

I agree Mike that would have been next level in weight reduction. However, I’ll probably stop here, because I want to be able to put everything back when I need to. So far everything I did is reversible.

 

[MS Coast]

There's that stereotype again...

Stereotype. Hmm. Well, no offense intended. But maybe so.

Looking at the numbers, our high today here on the U.S. Gulf coast was 63 F, and it looks like yours in Vancoover was 53 F. So, not so different.

I stand enlightened.

 

[Dushash]

So to reiterate 215g is the lowest one can go to still have all functions as stock, including ability to fly in light rain/snow (with conformal coating on top pcb) and fly in heat (with heat sink present).

Now I ventured to another extreme. Another little adventure. I decided to add to Mini 2 extra battery lol. Of course it will be heavier now, but just want to test it whenever I'll have time and weather will be compliant here.

So without long due, I just added original battery - so now I have ability to either fly with 1 battery or 2 batteries attached together. Of course with 1 battery it's 215g, but with 2 batteries it's 287.7g, so it's about 38g over 250g category. I think this setup with 2 batteries might have a bit longer air time (still remains to be tested).

So here's some pics of it hovering with 2 batteries. Pitch is certainly noisier than with 1 battery, but it has no issues hovering. Considering payload for Mini 2 is officially 81g according to DJI (correct me if I'm wrong) I think it should be just fine.

All telematics work for inserted battery: temperature of inserted battery, voltage and air time. However, since it's twice the battery now - drone doesn't know about added second battery, but it can see that voltage consumption rate is slower (because now current that is drawn is split between batteries) and correctly calculates percentage. Air time is counted down, but the rate of countdown is slower. So proper value is percentage - it is exact, as 2 batteries are identical.

 

[Dushash]

Here's some more pics

 

[Dushash]

Forgot to mention, that charging works too both in drone and in hub. Essentially second battery is just welded to plus and negative terminals. Neither drone nor inserted battery know that there is additional battery and because it's exactly same voltage - that means it will discharge and charge together with inserted battery without any issues.

 

[EpicFlight]

I agree. I will put heat sink back, because indoors it’s safer with it and it’s only 3g, so it’s going back to the drone. Outdoors we have 2F (-17C) and after flight chips were cold even without heat sink.

I'd put it back given how little it weighs.

Keep in mind that open to the air like that the cooling situation is massive, especially when moving, although prop wash is helping a lot with the board exposed too.

 

[Slawaw]

Forgot to mention, that charging works too both in drone and in hub. Essentially second battery is just welded to plus and negative terminals. Neither drone nor inserted battery know that there is additional battery and because it's exactly same voltage - that means it will discharge and charge together with inserted battery without any issues.

Is there a result in numbers?
I have 44 minutes.

 

[Dushash]

So just tested it hovering and it hovered 15 minutes more than stock Mini 2. So added second battery doesn't add 30 minutes, because obviously weight is more, but adds about 15 minutes more to stock.

To reiterate:
Lightweight or my "stripped down" 215g Mini 2 only hovers 4 minutes more vs stock.
Heavyweight or my "2 battery mod" Mini 2 at 287.7g hovers 15 minutes more vs stock.

I'm guessing for regular flights - I'll chose 215g version as it provides lower noise and better wind resistance and 4 minutes more air time.
For occasional flights when I really need more air time - I might use "2 battery mod" version.

 

[EpicFlight]

There's that stereotype again...

If the foo sh*ts....

 

[Dushash]

Is there a result in numbers?
I have 44 minutes.

1. So my stock Mini 2 - did 27 minutes (I don't know why not 31min like it says in DJI manual).
2. Lightweight "stripped down" 215g Mini 2 - did 31 minutes real hovering in my room.
3. Heavy 287.7g Mini 2 with "2 battery mod" - did 42minutes of real time hovering in my room (just finished test).

So if your 3500mah battery mod Mini 2 did 44 minutes - that's more than what I have. I suspect it's because there is a diminishing results: weight vs battery mAh. I suspect your 3500mah is optimal balance.

 

[Dushash]

Is there a result in numbers?
I have 44 minutes.

Actually I just noticed your weight of 374g and if it has air time of 44 minutes with that weight - that is excellent! Much better than my "2 battery mod" with 42min. I don't know why mine has such low time, considering it weighs 287.7g, but I suspect your battery is superior.

 

[Slawaw]

YouTube. Zolly. Info.

 

[Slawaw]

In ordinary life, we will not fly with the plastic removed on the drone. Then why take it off? Only for experiment because it is interesting to try. I find relief by way of a dead end. You correctly said that 3500 mAh is the most optimal size.
Even for record-breaking flights at maximum range on Mavic Air, he preferred not to remove the plastic, but to fly in its original form. Adding only battery capacity.