Dynamic balance on geared engines

After flying in Ben's and Aaron's planes, I felt like mine wasn't quite as smooth. Ben's is ridiculously smooth, like turbine smooth. Aaron's is also super smooth. Mine was fairly smooth but not like theirs. At cruise I felt a slight vibration in the yoke. I'd heard mixed things about dynamic balance. Some said it was BS... some said you can't dynamic balance a geared prop, especially if there is any slop.  

I talked to DynaVibe who make the tool. They referred me to a shop just 20 miles from my home base. I called the guy and he said it would work. He hadn't done a TwinBo but had done 421's. Said RPM's are RPM's... well for $400 /side I figured it was worth a shot. It took all day with about 5 runs on each engine. Right side went from .4 IPS to .02. Left side went from .1 IPS to .02. Flight home no more vibration in the yoke.  

I'll have a longer flight on Weds to test. What say you, $800 down the toilet or $ well spent?

no reason for the attached photo other than I took it while waiting around...

Contact info:

Tracy Van Iwarden
Aviation Specialties
(707) 451 2860

It works

Got a chance to test it out the ArticAir AC today. After the initial one didn't work and a return for repair, I'm happy to report I'm pretty dang happy with it. I feel nice cool air hitting the back of my head. It was over 100 degF today and it definitely made a huge improvement. It didn't freeze me out but it did bring me from dripping sweat solidly into no worries territory. If I had to guess I'd say it lowered cabin temps by about 15-20 degrees. I went for a gas run and there was a line at the pump, so I just let the engines idle at 1400 rpm and let the AC rip and was happy as Larry sitting inside with the storm windows shut and cool air blowing. definitely a leg up for this Tbone!

TBone Aircon

After a bit of a snafu I finally got the ArcticAir real AC 24v installed. Takes up about 2/3 of the extended baggage compartment but no biggie since I primarily use mine as a 4 seater. It's also technically a "portable" unit and I can fairly easily remove it in winter.  The first one they sent me didn't work... it blew air but wasn't cooling. I had to send it back for repair and now it blows cold. I had my mechanic install some anchors for it, since I don't want a 50 pound box becoming a projectile, and they also install a 60 amp breaker, power, exhaust out the tailbone and drilled some holes to route the blow tubes through the hat shelf.