READ NOTES AT BOTTOM ! ! !

I carefully marked a dot on the end of the spinner.  I removed the desiccant plugs so that I could turn the engine over easily while

checking the spinner for concentricity before drilling the holes into the mounting plates.

Once I felt it was going to spin perfectly I then clamped it into position.  I marked the locations for the 14 screw holes.

Not shown but I drilled all the holes using a #40 bit and then #30 and countersunk for the tinnerman washers.

Checked it for trueness again.  Came out perfect.

Clecoed it into place and then marked the 6 holes for the front plate and drilled the same way.  Disassembled it all and installed the platenuts.

I tried to maintain about a 3/32" spacing all the way around.

Now to fill the back side using .063 aluminum.

I made patterns again from my thick photo paper. Then transferred them to my plate and cut them out.

Since I'm using a wooden prop I guess is the reason why these are somewhat slightly different in size.

Riveted them to the back plate and then drilled, countersunk and then installed plate nuts. One on each cover.

I slightly sanded down the surface where I riveted it to the back plate and  you cant see the rivets any more.  Looks like I glued it in place.

I haven't added the screws and tinnermans here because Vans doesn't give them to you. 

Important "AFTER THE FACT" info.

Now obviously construction of this assembly takes place without the Cowling installed and since the back plate was previously used to obtain

the proper location of the Cowling fore and aft.  One would think once the Spinner was complete and the Cowling reinstalled everything would be

peaches and cream.... WRONG!  It was a rude awakening to realize that the back plate was never true from the start.  So moving forward it

would be very wise to spend the extra time and make a nice rigid mock up of the rear spinner plate way back when the Cowling was being installed.

Moving forward to present, once Prop adapter, back plate, Prop, front plate and crush plate are installed.  It would be necessary to verify that the

back plate runs true on its backside.  Since it is stamped from a flimsy yet soft piece of aluminum it is easy to bend it fore and aft get this flange

to run true.  If you discover there is air gap between the spinner and back plate, it would be easy to wax the plate, lay 1 layer of glass inside the spinner

and push into place.  Ultimately the back plate needs to be either flush with the rear of the Spinner or the Spinner precisely overlaps the back plate

the same amount all the way around.  I would say not more than 1/16" all the way around. I know that all the glass components you have  worked

with until this point have been crap.  The Spinner it the ONLY one that is very precise.  Keep in mind the back surface of the Spinner and the very front point is your only true frame of reference.  The back plate and front plate merely mount the Spinner and hold it running true.

This pic shows what I realized later.  The Red arrow shows where the back plate was bent forward about 1/8" and the Yellow arrow shows where

the plate was fairly flush with the back of the Spinner.  Now this would have worked fine but before I fit the Cowling, I sanded this extra overhang

away to make it flush with the plate and obviously to make it "look good".  But if I hadn't sanded it away, the spacing from the tinnerman washers

and the back of the spinner would have varied around the spinner.  No one would have probably noticed this but, I'm all about symmetry man. ;o)