"Here is the reply I eventually received from support.  I thought they might post something here, but they didn't... Hi John,  Most of our engineers normally fly their multicopters without the rings, just making sure to hold…"

"What I ended up trying was that knobby foam that they sell for lining toolbox shelves (had a lot of it left over) like those pads posted in the first reply.  I cut a piece large enough to wrap the whole battery and then tacked it into place…"

"I followed this procedure and it worked well.  I finished off with a little Dremel reamer bit.  Thanks.   Good idea. "

"Hi, I think I found a solution to the problem of the plastic rings that are a bit too small to fit on the base aluminium collet. The problem was : -plastic rings have an internal diameter of 6 mm -the base of the aluminium collet is 6.3…"

"So without the insert you would achieve both of these objectives with the only downside being that the propeller may be off center by ~ 1 mm.  Carving out the insert would actually achieve three objectives but is somewhat non-reversible.…"

"Hi John, As long as you can get the prop to push the tapered locking ring down to secure the prop adapter on to the motorshaft. It wouldn't matter whether you took the aluminium shoulder away or trimmed the plastic insert. The plastic insert is…"

"From this discussion, here are possible reasons for failure: The male threaded section (of the collet) is bottoming out in the nut section before clamping is achieved The collet flutes (slotted section of the lowest piece) are not gripping enough…"

"I guess I could get out the trusty Dremel and ream it out a little but as you can see that only would buy .5mm(?) beyond just having no plastic collar.  Is it really better with both the collar and the aluminum "ledge" on the shaft? "

"Hi John, Did your prop come with a selection of these plastic propeller inserts, if so this is so that the prop can be used with a selection of prop adapters with differing shaft diameters. I presume that you have selected the ring that is the…"

"Yes I am admit I am a little reluctant to proceed without some advice from the manufacturer given all the issues folks seem to have with prop attachment on these beasts.  Unfortunately they are out for the week + their response time isn't…"

"John, I have the same problem!  I'm using the 880Kv motors and 11x4.7 props supplies from 3D Robotics with my Quad-C. Last night I put the collar in the back of the prop, balanced it, then slide it onto to the threaded prop shaft…"

"First the whole assembly needs to be on the motors shaft and you need to tighten with a nail in the hole till the nail almost bends. Then take a picture again."

"I understand that the directions say to put in the plastic collar but my metal hub has a raised inner ring that is the same size as the ring: and if I put the plastic ring into the propeller I can't get the hub to clamp down on…"

"Yes I have plenty velcro laying around but I do like the foam toolbox tray liner suggestion.  I have half a roll of that left over from lining my electronics toolbox."

"John, I did mean on the transmitter, but you've managed to sort it now yourself, I must have picked the instructions for an older version of the DX7. Happy flying."

"John, I am glad you sorted it out. I intentionally did not look up your DX7 TX manual because the firmware seems to change with these systems. If I built you a 'how-to' it would have surely been wrong. In fact I have two DX6 manuals that…"