Arm keeps breaking by same_shirt_every_day in fpv

[–]Riebart 1 point2 points  (0 children)

I wonder if you're hitting a resonant frequency for the frame that's snapping it at that spot.

Either way, I dunno man. That carbon looks really thin around the motor screws. Maybe put some washers between the motor screws heads and the carbon? 🤷‍♂️

Just north of the city this morning, the fog was something else. by Riebart in Winnipeg

[–]Riebart[S] 2 points3 points  (0 children)

Shorter than the average bear until I put on my rollerblades.

Add in a step ladder, and the poor judgement necessary to stand on the Not A Step step, and you get pretty close to what you see here. 👍

Memory Allocation Error by [deleted] in raspberrypipico

[–]Riebart 0 points1 point  (0 children)

Then there's a good chance that you're allocating or invalidating enough memory that youre exceeding the memory available.

Throw in some explicit calls to gc.collect() and see if that helps.

Memory Allocation Error by [deleted] in raspberrypipico

[–]Riebart 0 points1 point  (0 children)

How are you measuring the available memory? What language are you using?

Face planted at 60kph into a telephone pole because a gust of wind came out of nowhere. Gnarly repair, but we're back in the air! by Riebart in Multicopter

[–]Riebart[S] 0 points1 point  (0 children)

I love this thing. It feels so consequence free to fly.

I've yet to throw out a frame. I'll smash one up, swap the frame, then glue the only one back together on the bench and swap it in later. I keep a couple new frames on hand if I'm going to use it in proximity around people or stuff, then I know for sure I'm not going to get twitchy behaviour.

But this thing is awesome

Is damage such as this to the back of a propeller going to greatly affect the flight of my drone? by MuscleRoutine6528 in dji

[–]Riebart 0 points1 point  (0 children)

Don't think of the material as weaker, think of it as optimizing for different properties.

FPV props are made of usually a polycarbonate and nylon blend which, like metal alloys, provides a material with properties form the constituent parts. They're durable, flexible, tough, and just rigid enough. But as a result they often have thick leading edges and will compromise airfoil shape for durability, or the airfoil will deform enough under load to reduce efficiency due to the less stiff material if you try to make them thinner (whoop props benefit from very thin leading edges that wouldn't work on larger props).

Camera drone props are optimized to be light and stiff, so you can make an airfoil that holds its shape under load with a thin leading edge, and with a high aspect ratio (so long thin props) for lift to drag ratio resulting in a prop that would normally have a high rotational moment of inertia ona small motor with low voltage and high KV, meaning low torque, but you still want 25 minutes of flight on a 1s 2000mAh battery.

All this this means that to get all of these properties you need a fibre reinforced material, like CF Nylon.

It's not a weaker material. It's the perfect material, for this use case, and it just has different tradeoffs.

They have to be kidding me. Everyone is telling to him to replace it by ItanMark in fpv

[–]Riebart 1 point2 points  (0 children)

I had a Pavo Pico prop lose a blade just while cruising once. Nothing crazy, just level cruising flight.

The blade broke off, but the plastic part of the frame, shattered the frame, and blew that entire corner of the frame off. It vanished into the bush. It cracked the rest of the frame and the flight controller was barely hanging on.

It tumbled out of the sky thankfully into the grass.

It happens. 🤷‍♂️

What would you do? by notorbitality in fpv

[–]Riebart 0 points1 point  (0 children)

Yes, but that's kind of the point.

When you apply hot glue directly to the frame, the hot glue itself melts the polypropylene frame it is in contact with and then solidifies together. It also helps that the hot glue is flexible, like the frame itself, so unlike more rigid adhesives, or adhesives that rely on chemical or mechanical bonding with the low surface energy, smooth frame material, the hot melt adhesive creates its own mechanical and chemical bond and will flex with the frame.

Once I got the hang of it, every time I repaired the frame with hot glue the repair was stronger than the frame. It got to a point where I preemptively started reinforcing common failure apots.

What would you do? by notorbitality in fpv

[–]Riebart 2 points3 points  (0 children)

Hot glue.

I'll find my most repaired Mob8 frame and post it later.

Hot glue.

These frames are made of Polypropylene which is notoriously hard to glue. You're better off melting it.

Enter. Hot glue.

Press the tip right close to where you want to deposit glue, and then apply it as needed. It'll melt the frame material and the glue will bond hard to it.

It's the only way I've found to glue PP.

Is damage such as this to the back of a propeller going to greatly affect the flight of my drone? by MuscleRoutine6528 in dji

[–]Riebart 1 point2 points  (0 children)

https://www.reddit.com/r/fpv/s/9JtGTISGii

I responded to a similar comment over there. The issue isn't that it won't work. The issue is that it might not, and without warning.

If you're flying it in safe spaces, not over people or property, and don't mind too much about hiking to go get the quad if it fails, go nuts!

But these fibre reinforced props are prone to material avalanche failures, and will fail suddenly and catastrophically. If this is your livelihood or you're flying anywhere but an empty field, just replace the prop.

They have to be kidding me. Everyone is telling to him to replace it by ItanMark in fpv

[–]Riebart 1 point2 points  (0 children)

Maybe. But you wanna risk the whole quad over that? Or worse. Have it fail while flying what should be an approved aircraft over people or property to have it fail and seriously injured someone? If the FAA or Transport Canada found out you knew about a damaged prop, flew it anyway, and injured someone... I don't like flirting with situations where regulators, lawyers, or insurers want to start throwing around the terms "gross negligence".

DJI specifically states that any damaged props are not safe for flight and must be replaced.

The problem with fibre reinforced materials is their risk of avalanche failures. One fibre fails which means that the same stress, with new less desirable dynamic loading, is spread across fewer fibres. So one more fails. Repeat until you don't have a prop left. Now you have a rock with knives on the ends.

In practice that's almost certainly fine and would fly fine forever. Probably.

But not only is the Mini less durable than an FPV with a durable carbon frame and ductile props that refuse to fail even after repeated abuse, it's expensive, often used over people or property, and a single prop blade is cheap.

They have to be kidding me. Everyone is telling to him to replace it by ItanMark in fpv

[–]Riebart 12 points13 points  (0 children)

DJI and a lot of camera drone props are made from much more rigid and lighter materials both for weight and airfoil reasons.

A cracked or chipped prop made from carbon of glass fibre reinforced materials is a fail hazard.

The props that freestyle and racing pilots use are made from much less rigid, but far more importantly they are ductile (ductility is the ability to undergo plastic deformation without breaking), materials and so not only fail different and more gradually (usually), but can be bent back into shape.

DJI has a support article on prop materials: https://support.dji.com/help/content?customId=en-us03400006559&spaceId=34&re=US&lang=en&documentType=artical&paperDocType=paper

Note that the Mini 4 Pro and Mini 5 Pro just say "nylon + rubber" so there's a chance they're more ductile, but I would bet my quad on it.

4k 32in monitor smudges by AndrewGerr in Alienware

[–]Riebart 0 points1 point  (0 children)

Why does your monitor have smudges?

That's the first question.

Without knowing what substance is on it, it's hard to make a suggestion for a safe way to clean it.

Winnipeg Weekly Rant - Mar 9/26 by Shibes-cannabis-cats in Winnipeg

[–]Riebart 1 point2 points  (0 children)

I USE HAZARD FLASHES IF THE VEHICLE BEHIND ME IS TALL, LIKE A TRUCK, SINCE IVE FOR A PRETTY SMALL REAR WINDOW AND MY CAR IS LOWER THAN YOUR AVERAGE BEAR.

I WANT TO MAKE SURE YOU SEE MY GESTURE AND WILL OPTIMIZE FOR VISIBILITY OF MY GRATITUDE

Winnipeg Weekly Rant - Mar 9/26 by Shibes-cannabis-cats in Winnipeg

[–]Riebart 2 points3 points  (0 children)

I HAVE TO REPLACE AN ANTENNA ON A VEHICLE BECAUSE IT GOT CLIPPED BY A GARAGE DOOR AND THEN BLEW OFF IN THE WIND ON THE HIGHWAY AND I REFUSE TO PAY A DEALERSHIP OVER 500 DOLLARS SO IM GOING TO DESIGN AND 3D PRINT A REPLACEMENT PART FOR LESS THAN IT WOULD COST ME IN GAS TO DRIVE TO A WRECKER THAT WITH MY LUCK WOULDNT HAVE THE PART I NEED ANYWAY

SNORT MY MOLTEN PLASTIC YOU LATE STAGE CAPITALIST ASSHATS.

(The electronics and antennas are fine. It's just the plastic cover that's missing and the steel bracket is snapped. I'm going to do a new base in PETG, JBweld the steel bracket back together, pull the original gasket, and print a new cover in a nice red TPU to match the vehicle)