I'm Posting a Tip by Rodney Williams as it was published on our website www.helmo.gr
I hope that will solve your problem...
[size=13pt]"HOW TO PAINT YOUR PROP SPINNERS"
by: Rodney Williams
For decades I had problems painting my prop hubs, when it came to applying more than one color on them.
I would use masking tape, which work's sometimes. You can go to LSP's web site and look up my 1/24th scale P-51D Mustang; "NOOKY BOOKY- II." Boy-O-Boy, did I have a problem painting that spinner. This story was posted sometime in 2006.
Recently I got the bright idea to do the following:
I have several sizes of "Evergreen Styrene Tubing," so I selected a tube which has a inside diameter of about 7/16"/21mm.
I sanded the inside of the tubing at a 45 degree angle then "dry fit" it to the spinner.
It looked like I could use it to paint two different colors on the spinner, but how will I secure it?
I added some thin-downed ELMER'S white glue to the insider of the tubing..
I just eye-balled my alignment, then let the glue dry over night.
The next day I checked the alignment and it looked ok.
I put some water inside the tube to dissolve the glue, then removed it.
I cleaned up the spinner and tube, then let the parts dry.
I sprayed on the lighter color of my Tamiya paint onto the spinner and let it dry overnight.
The next day I applied my section of tubing and then added the thin-down white glue.
I just followed the above procedure then sprayed on the black color.
After the dark color dried, I added some water to the inside of the tube and took it off.
My last photo shows the front of the model, which to me, meets my expectations for a nice looking two tone prop spinner.
Look at my first two photos : The black paint looks like it has "orange-peeling" on the blades. This is due to the paint not being thinned enough. I sanded the blades with some 800 grit wet/dry sandpaper, then repainted them with some "thin-downed" paint.