crash90, I use a Dave Brown spinner also, and agree with Icebird that the knurling isn't agressive enough on a Dave Brown spinner. Sandpaper help increase the friction especially with carbon fiber props and worked great with my BME 102, and all right with my BME 105. The 110, though, is an animal, and needs more.

I then tried a pair of 1/8" music wire pins glued into the props that extended 1/4" from the prop so as to engage matching holes drilled into the spinner backplate, and pinning the prop to the backplate cured the problem. To make things a LOT easier, I used the spinner backplate holes as a drill jug and opened up the holes to accept a pair of 10-32 bolts and now I just bolt the prop to the spinner backplate (using nylon insert locknuts). Then, using the stock prop nut, install the prop/backplate assembly to the engine and I'm good to go with ZERO prop movement. The holes are drilled so as to allow the prop to be at approximately the 9 and 3 o'clock position for starting. The prop washer and the crankshaft prop thrust face are about the same diameter, so drilling the holes outside this dimension allows room for the locknut and flatwasher on the backside of the spinner backplate to not interfere with the thrust face.

I've had zero problems since using this method, and for me, it's the permanent solution. You might note in the picture, I still use a bit of sandpaper.