A little help with motors please

[tipsy trucker]

I'm getting the parts together for my first build; A repile 500 (tbs discovery clone) but I'm a little bit stuck when it comes to motors.

I had settled on sunnysky 2212, some seem to say they're not powerful enough while others say the opposite. The figures say 1020g thrust with a 10" prop (980 kv) so they sound ok, to start with at least, to me.

However, they never seem to be listed as cw or ccw. A little googling found that the prop mounts are all one direction but replacements can be found for about £3/pair

Do I just reverse the esc somehow? Or use all four spinning the same way? Or am I barking up the wrong tree altogether?

[ched]

Me again  ::)

The way quads work is 2 motors spin clockwise and 2 anticlockwise. Same rotation on diagonal corners.
The reason for motors being called cw or anti-cw is referring to the direction the nuts are tightened. You should tighten the prop nut the opposite way to the direction the prop will spin. This ensures that the nut tightens as the prop spins not loosens. A little caveat is that generally small quads have lock nuts on and then it's not as important as the nylock nut doesn't really loosen with vibrations.
You can reverse the direction of rotation by swapping two of the motor to esc wires, simple as that. On smaller quads with newer esc you can even do it via software. Some motors are connected to the esc via bullet connectors that are easy to swap.

So weight and thrust:
My F450 weights about 2kg and according to the specs the dji 920kv motors provide 1200 grams of thrust per motor. So a total of 4800gms = a little over 2 x thrust to weight ratio. This is LOW a quad for acrobatics or racing will have a thrust ratio of over 8 to 1 probably quite a lot more!
A camera platform quad will have a lower thrust ratio as you are not intending to do rolls, flips and fast maneuvers but you want longer flight time.   

[tipsy trucker]

Ahhh, so I'd figured right and the prop adapter things (2cw & 2ccw) would solve the problem....... but I should be looking for a bit more oomph?

[ched]

Ahhh, so I'd figured right and the prop adapter things (2cw & 2ccw) would solve the problem....... but I should be looking for a bit more oomph?

Can you post a link for the bits you are thinking of? Sometimes it's easier when there is a link to a product or page.

[tipsy trucker]

These (obviously, 2 sets): https://www.ebay.co.uk/itm/2pcs-CNC-Aluminum-Propeller-Prop-Adapter-CW-CCW-for-Sunnysky-X2212-X2216-Motor-R/153110809364?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

And these (4 of): https://www.ebay.co.uk/itm/SUNNYSKY-X2212-2-4S-Brushless-Motor-For-RC-Airplane-Fixed-Wing-Aircraft-G0N1/123229171674?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

I hadn't got as far as what prop's to go for except probably 10" rather than 11"


But, given what you said about thrust:weight, I think a re-think may be in order 

[ched]

OK so had a little bit of checking and found a company who lots on here use for quad stuff that have the sort of motors you are looking for.
https://www.unmannedtechshop.co.uk/mt2216-810kv-muticopter-motor/
They are £14 each but come with a pair of 10" props and the prop adapters. They say they are suitable for an F450 which the same arms as the reptile. So should be fine.

The sunnysky motors on ebay are good but there are lots of fakes kicking about. So make are they are genuine.

One thing you can do is say search ebay for tbs discovery quads and see what components they are using and how much people are asking.  That way you might get a good spec that is used by a few sellers.