Arresti III Nose Ring...

UPDATE November 10, 2004 - Preparing the newest Arresti, I decided to recheck the setup on both.  The procedure outlined below results in a solid and effective nose ring mounting system, in conjunction with the modified Pollitt nose rings.  This is cheap, easy, and works perfectly.

UPDATE August 21, 2004 - Today, VERY successful flights on the nose ring installation.  After four flights, with LOTS of throttling, and a pretty good workout, it is solid, and works excellently!  The Hyde Mount ALSO worked well (I know that is no surprise to anyone!)  But - the REAL surprise was the noise reduction with the new Aeroslave CF pipe AND the nose ring/Hyde mount.  This baby is QUIET in the air....and it sure works!!!

After installing a real Hyde Mount, I found it to have too much movement, so off I went into "build your own" land regarding a nose ring.  After asking on the NSRCA discussion list about various ideas of making my own, I struck out on a composite of the various schemes.  Slightly challenging, but lessons learned on how to do the next one.

The "nose ring" proper is a machined aluminum part, with a rubber o-ring insert.  I bought these from Andy Pollitt.  They are EXTREMELY tight on the crankcase, and I'm not sure I'll like that over the long haul, but we'll see. [Update - The aluminum channel the O ring rides in is far too tight.  I loosened the channel by using a Dremel narrow cutting bit.  It ain't CNC, but it permitted the O rings to fit properly, and not so tight that the rotation benefit of the mount was compromised.  I am now quite happy with the Pollitt nose ring, after modification.]

The rest of the affair is a collection of 1/8" ply, 1/8" x 1/4" spruce sticks, epoxy, and CA.  Of course, I have *no* idea if this will work yet, but so far on the bench it seems to do what I'm after.

I know everyone wants to know.... the WHOLE assembly, installed, 1.1 oz, just as you see it.  So, net change from the original Davis/Lockhart well-nut mount to the Hyde mount with nose ring is a REDUCTION of .1 oz!!!!

To begin, I measured the ply plate I'd need, ended up with 2" x 2 1/2".	Next, all the trusses/longerons.  Made those out of the spruce, CA'd and clamped.
Pic above is the finished deal, with the trusses/reinforcements added.  Note the longerons go THROUGH both the firewall AND the nose ring mounting ply plate.	This view shows the side I couldn't brace due to the header and stuff.  Since it is lower left, it should be okay. (Also note the Hitec HS55 throttle servo in this view.  VERY sweet setup!
This view shows how the Pollitt nose ring mounts;  4-40 screws from the FRONT into the tapped aluminum part.  The idea is to unscrew from the front, remove the engine bolts, and the whole thing comes out.	The concept is that the front ply plate has the truss "T" beams penetrating it, AND going all the way through the firewall.  These are snug-fit, then epoxy applied that has had glass fibers added for filler/hardening.  The ply plates going across the beams is intended to limit torsion.  Angled trusses from firewall to top longerons intended to limit CCW rotation.