So close! No room for the battery strap on my QAV-R2

Duck

Active member
I am finishing my first quad build and I've run into yet another problem with the stack height. I went with the Kakute F4 v2 and I am very happy with how it built. I only magic smoked one while learning to solder better :) However I did not realize how close my stack was going to be to the frame. I've tried a few ways of reducing the standoff heights without a lot of success. The biggest issue is that most of the standoffs could be 1mm shorter but I can't find any in that height. The immediate problem is that my battery strap won't fit between the frame and the VTX without touching it and being a major risk of ripping off components from the board. I was planning on no GoPro so my battery should be balanced over the CG but putting it that far forward means an offset battery strap won't cover it. If I wanted to fly it as is, I would need to zip tie the battery in place :(


20190525_230418.jpg


At this point I am out of good ideas. Can anyone make a suggestion?

I can see the following options:
* Ditch the VTX from the stack and buy a new one for rear mounting. There is room in the back.
* Zip tie the batteries in place.
* Try to cut down my standoffs by 1mm. Anyone know where to by 3mm or 5mm standoffs?
* Buy a longer battery.
* Try to find 2 very narrow battery straps and go on either side of the stack.
* Bottom mount the battery. The ESC _should_ have enough clearance to avoid ripping anything off.
* Buy a GoPro for weight :(
 

ElectriSean

Eternal Student
Mentor
Rather than standoffs you could try using 2 nuts. Alternatively you can cut or sand down what you have, nylon threads should be easy enough to repair with metal screws.
 

PsyBorg

Wake up! Time to fly!
I would remove the vtx from the stack and hang it under the back part of the top plate.

It opens up the center for using 2 battery straps which I fully recomend. It also gets it out in the open for better cooling. You dont hold the heat in and that heat does not transfer into your battery.

Edit: I use vtx meant to be put in stacks and just zip tie them to the back if the top plate and have had zero issues doing so. You will not need to buy a different vtx just for that move.
 
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Duck

Active member
I would remove the vtx from the stack and hang it under the back part of the top plate.

It opens up the center for using 2 battery straps which I fully recomend. It also gets it out in the open for better cooling. You dont hold the heat in and that heat does not transfer into your battery.

Edit: I use vtx meant to be put in stacks and just zip tie them to the back if the top plate and have had zero issues doing so. You will not need to buy a different vtx just for that move.

I don't quite have my quad hardware mounting confidence yet. Can you share a picture of what you might think this would look like? How do I isolate the VTX from the top plate?

If I could find a frame that had two 30x30 stacks I would have been happy. My runcam split doens't fit either but I have given up on that one. I found a few frames like this but none I liked for other reasons.
 

Duck

Active member
Rather than standoffs you could try using 2 nuts. Alternatively you can cut or sand down what you have, nylon threads should be easy enough to repair with metal screws.

My first attempt at shortening the stack was replacing the 6mm standoffs with 2 nuts. It worked OK but I ran into problems with the thread length. Cutting the standoffs should resolve it. I'll try a few combinations here and see what it gets me.
 

PsyBorg

Wake up! Time to fly!
No need to isolate the vtx. Zip tie it upside down to use the top plate as extra heat sink as well as be able to see settings.

I mount mine like this. 20190529_005814.jpg
 
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Duck

Active member
Well, I gave moving the VTX a shot and it is too large to fit between the back standoffs. I have a unity pro and a metal cased RMRC VTX so I was just about to resolder everything. Then I decided I really didn't want to do that. I had taller standoffs lying around that I bought to see if I could fit my Runcam Split. That still didn't fit even with the taller standoffs and made it so I couldn't use the camera side plates. Well I finally got my rubber camera mounts that Lumenier includes in the slammed kit. I threw those on and everything fits!

20190802_222813.jpg


This is a huge waste of space, puts the CG up really high and will likely snap something right off with the right hit given the longer standoffs. But I didn't need to re-solder anything and it was physically ready to fly in 5 minutes! Bonus: the taller standoffs are orange!

I still have a little bit of tweaking before I am ready to send it. This is my first build and the lack of sane defaults in everything so far is making me paranoid. I already out that the RX channels were all reversed again. Hopefully we should be flying within the week.
 

Duck

Active member
It flew! My DVR is not setup yet so you could claim it didn't happen but it did! The roll rate was pretty slow and I accidentally disarmed while trying to change the flight mode but that barely counts as crashing. I only have 1 high C 4S pack and it was damaged in the hard landing so I have to wait for a pile of batteries in the mail. Once they arrive I'll get a good flight video.

I did get quite a bit of video noise, a lot more then my vortex 180 that I flew in the same spot so I will have to figure out what is driving that. Hopefully a little DVR footage will give me a more accurate picture of what is going on as I won't be holding on for dear life while trying to watch video noise.