Building an electro hub with 350qx electronics.

zcar300

Junior Member
Hello,

I'm getting tired of having to take my Blade 350qx3 completely apart to replace any one part. I've looked for aftermarket frames and the only thing I've found is $125. I don't know enough about flight controllers to know if the one in my 350 will support different sizes of frames.

Ideally I'd like to take all the electronics and move them to an electrohub with the new angle arms. But the product page doesn't say what sizes you can make with either set of arms. I'm not even sure the motors will mount to the electrohub motor mounts though.

The stock motors are 1100kv and the ESCs are 10amp. The stock props are 8.5 inches.
 

BankNYank!

New member
Mentor
Hey zcar300, welcome to the forum!

When dealing with a production multirotor like the 350qx the best advice I can give is to make the booms the same length as the booms on the original frame. I believe those motors are laid out in a standard 'X' configuration and if I remember correctly the flight controller is a little bit forward. At least I think it was on the v1 350qx I had. As long as you get the flight controller in reasonably the same location and cut the booms to reasonably the same length you should be good to go. If you do a google search there are people who have done this same conversion with plenty of success.

The reason I say to make the booms reasonably the same length is because this is what the flight controller has been tuned for. You could go with longer booms but then it may get a little sluggish where as shorter booms may make it a bit twitchy. So the best easiest advice I can give is that if you want it to fly with the least amount of issues build your new frame to as near the old frames specifications as possible and you should be good to go!

I hope this helps and if you have any other questions please feel free to ask!
 

zcar300

Junior Member
Yes that is a great answer. I kinda had a feeling that the FC needs to have the same size frame after watching videos on PID tuning. It makes total sense that it would handle differently with a different size frame. Since you can't change the PIDs. That one replacement frame I found says it is 378mm. I'll measure my 350 later.

I'm also concerned about the weight of the electrohub. Although the 350 is designed to carry their 160g gimbal/camera, I don't want to weigh it down too much with my old heavy GoPro 2 with it's case and FPV gear. My GoPro with case weighs more than their gimbal and camera put together.
 

BankNYank!

New member
Mentor
I'm just taking a wild guess here as I do not own an electrohub but I imagine the weight of the frames should be similar. If nothing I would think the electrohub would be lighter. Of course that depends on what you use for booms. I'd start out with wood since it's cheap, durable and helps with vibration dampening even though it is probably the heaviest of the popular boom materials. The nice thing about using a frame like the electrohub is that you can change stuff out and try different ideas.

As far as weight of equipment the best I can offer is to sit down with a scale and some scratch paper and work things out. If you don't have one, a small kitchen scale is invaluable and you can pick one up for under $20 if you shop around.

If you plan on adding things like gopro and fpv I recommend keeping an eye on your cg. Draw an imaginary (or real) line from front right to left rear motors and do the same for the other two. Where the two lines intersect should be your CG mark. CG isn't as important on a multirotor as it is on a fixed wing but if you have it too far outta whack you'll be causing motors to work harder than others and if it's really bad you can actually lose some of your headroom needed to maintain stable flight and maneuverability.
 

zcar300

Junior Member
So I still need to know if the angled arms or even the normal arms are long enough to make a 378mm quad...
 

C0d3M0nk3y

Posted a thousand or more times
So I still need to know if the angled arms or even the normal arms are long enough to make a 378mm quad...
The arms are just square dowels that you can get at a local hardware store. You can cut them as long or short as you'd like.
 

BankNYank!

New member
Mentor
If your going to use the electrohub what C0d3M0nk3y is telling you is accurate. You can cut the booms to any length you need.

The measurements you make on your 350qx should be left front to right front and left rear to right rear from motor shaft to motor shaft. You want to make sure these measurements are the same. I think they are if I'm not mistaken. Then measure right front to right rear. Then you want to measure from left front to right rear. Write all this stuff down so that when you build your electrohub you can get the frame as close as possible to the factory one. The closer you get it the less anomalies you should have.
 

zcar300

Junior Member
Yes, I realize that. But since we're paying for square booms with the kit then I would like to know if they are long enough for my application. Plus I'm really more interested in knowing if the angled arms are long enough since that's not something I can just go buy and cut down to length.
 

BankNYank!

New member
Mentor
I'm not sure what you mean by angled arms. Unless your talking about the Angled Arm Bracket Kit.

The electorhub kit comes with everything you will need to build the electrohub frame into a quad that will accommodate the electronics off your 350qx... except maybe the externally mounted gps antenna. They have a little trick they do where they use a landing gear mounted sticking up (as opposed to down) as an attachment point for fpv/telemetry antenna. I suppose you could do something like that but the particulars are up to you.

Short answer:
Yes the booms are more than long enough. You'll probably end up cutting about a half inch off.
No, you do not need the angle arm bracket kit. (If that's what your talking about).
 

zcar300

Junior Member
Yes that is what I'm talking about, hens the name. Yes i know I don't need the angled arms but I do want them. Which is why I've been asking repeatedly.
 

BankNYank!

New member
Mentor
As I stated before I do not own the electrohub and therefore I do not understand what the Angle Arm Brackets do.

If your looking for your electrohub frame to share the similar "deadcat" style boom layout as the 350qx, the frame can already do that.

If you have further question about the Angle Arm Brackets I will leave that to someone familiar with the product to answer.
 

C0d3M0nk3y

Posted a thousand or more times
Yes, I realize that. But since we're paying for square booms with the kit then I would like to know if they are long enough for my application. Plus I'm really more interested in knowing if the angled arms are long enough since that's not something I can just go buy and cut down to length.

Sorry. I didn't realize what you were asking. The stock booms included in the kit will make an X quad somewhere in the 500 mm range. You can cut them down to 378.
 

C0d3M0nk3y

Posted a thousand or more times
I'm very sorry. There's no excuse but today was rough.

No worries. Put up a thread with your progress on swapping out the electronics whether you go with the ElectroHub or with something else. I'd be interested to see it.
 

zcar300

Junior Member
I sure will. I haven't decided what I'm going to do with it. Just have to weigh the options and pull the trigger.
 

zcar300

Junior Member
I finally got around to getting a frame. The motors will not fit. The holes are too close together on the motors. Looks like the 350 is grounded. I'm not dealing with the stock frame anymore. Besides, I built a Morphite 180 and it is so much more fun to fly. I just can't use it for aerial photography.
 

Merrixs

Member
If I may, you are dealing with wood booms. Wood is one of the easiest hackable things we can work with. I am sure you can mount those motors if you look into the different ways people have been mounting their different motors.