Using the 10mm adapter bolt
 

Bill,

I am in the process of installing a BT 43ei on my airplane and wish to use an aluminum spinner. I have looked at the supplied adapter bolt and am confused as to how to install the propeller with this bolt. The bolt has an area that is 10mm in diminsion. Do I drill out the prop, backplate of the aluminum spinner and the front washer to match this area? Is there any drawings or pictures of this adapter bolt that I can look at?

Thanks,

RE: Using the 10mm adapter bolt
 

I don't know what brand of spinner you have, but my Tru Turn spinner had to have the backplate reamed to .394 inches. Depending on the prop, it may have to be reamed also. Trying to drill it might not be the best answer, as a drill might not get the hole dead center. You can imagine what the vibration levels will be like if its slightly off center. Either ream it, or use a lathe to bore it. The same holds for the prop and washer.
Hopefully someone in your local club has the tools to do it. A machine shop would charge a pretty high price to do the work.
Good luck with it.

RE: Using the 10mm adapter bolt
 

You would drill the prop and spinner to fit. You shouldn't need to drill the prop washer, since it's a stock item for your engine.

To drill accurately, you'll need a drill press. Chuck a drill bit that is the exact fit into the spinner backplate. Use that drill bit to center the spinner backplate and then clamp the backplate down so it won't move. Now you can install the larger bit. Drill at slow speeds with plenty of lubrication. The new hole will be exactly centered. Drill the propeller in the same manner.