I recently broke my second 250 frame Broken arm, just like the first one

[G+_Mr ROKnBOK]

I recently broke my second 250 frame. Broken arm, just like the first one.

I had a spare frame (anticipating I would need it) and decided to change the design for this rebuild using the myriad, multiple parts of the frame I had. This is what I came up with:

I sandwiched the RX (front) and the FPV RX (rear) between two extension plates. They are lower than the props so, theoretically, I could use 6-inch props. (couldn't I?)

I attach the battery to the bottom and I wanted to hang the cage off the bottom. Realizing how difficult this configuration would make it to switch batteries, I decided to use the last two extension plates I had to create individual cages on the underside of the front (to protect the FPV camera) and the back. That left a large enough space to fit a 2200ah battery.

I haven't flown it yet; it's been rainy and windy all day.

[G+_Jeff Brand]

If they clear the frame then technically you can use bigger props. However, that changes the load on the motors which are now moving larger volumes of air. This changes the RPM and torque numbers which means your setup may be inefficient until you switch to a lower KV motor.

 

Definitely try it and report back! This is something I don't have much experience with and generally just take specs as given to me until I have enough parts to tinker.

[G+_Mr ROKnBOK]

Jeff Brand that's great information, thank you!

Do you think 6" props would burn out the 2300kv motors (or damage them in other ways), or just be inefficient?

[G+_Jeff Brand]

I don't think the extra inch will burn them up. I just realized I use a 6" on a 2200kv for some flitetest foam airplanes with no problems. Of course, the sustained load is a fraction of a quad setup.

 

You'll likely notice slower response times to throttle changes compared to the smaller prop, too.