Russ hit on what I think is the the problem with guys taking off with Nexstars (and other tricycle LG models), which is a crooked nosewheel, and also overly sensitive steering. As club instructor I have maidened 3 or 4 of these planes, and a couple of years ago I actually bought one myself while on a 2-week business trip because I found out there was an AMA club not far from my hotel. Remove the flaps and disable the annoying AFS) and it is a fine trainer, and remove the wing naca pieces and it is a fairly capable aerobat. How many trainers will fly a decent KE, slow roll, inverted flight, or even a 1.5 negative snap roll to inverted into an outside loop?? This plane will do it.

In general, however, I vastly prefer taildraggers such as the Phoenix Extra because the tail will lift quickly and no matter how badly cockeyed the tailwheel might be, it doesn't matter because it's going where that big rudder tells it. This is why - with very moderate control surface throws and generous expo - the Extra might work out to be a workable second model, although it is not nearly as rugged and forgiving as a Sig 4-star, WM or GP supersport, or a spacewalker, or a H9 Pulse. Those are excellent second planes.

I know thie is the extra forum, but as far as the nexstar the front wheel when aligned correctly will stop the pulling right on take off. It has to be slanted towards the left, trust me and try it if you have one, you will be suprised the rudder will not have to be used at all. I can knife edge with the nexstar my nexstar is fixed and ready to fly again now it is not a virgin crash model i can have fun with it

Racerchuck: I'd keep the kit wheels, they are just fine. Spend that money instead on a dubro 2-56 pull-pull kit and use the Phoenix brass stuff for something else like maybe a boat! By doing this and using regular steel 4-40 rod instead of the CF/Brass that came with the kit for aileron and elevator pushrods, I saved a total of 0.55oz for $5! As far as the bouncy.... just kick both ailerons (using Flasperons mode) up ~15mm (aka airbrakes instead of flaps) and the plane will land a little faster without bouncing. Works great, keep a little power in it for the extra drag- a click or two. I did that on a still evening yesterday and had a beautiful 3pt landing that didn't bounce at slightly faster than trainer landing speed. This plane is so wingy that the wings will make ANY wheels bounce at what looks like a good landing speed.
Without airbrakes, if the wind is 10+& puffy and you slow it down enough to land without bouncing, it tends to get a little wiggly in roll & stall as you try and slow down to land. I now use airbrakes for every landing. I have them on a 3 posn switch, so up is flaps, mid is neutral for flying, down is airbrakes. I never need the flaps, so I may go to a second level of airbrakes on that switch, say 20mm. I'm at 13 right now. I'm tempted to go flaps for harriers, but it seams to rock more side to side with flaps (i.e. aileron input needed constantly).

EDIT June 7,09: I now have theailerons at neutral for normal flight, mid position of the 3 pos'n switch is 12mm spoilerons (up from neutral), 3rd pon is 18mm of spoilerons. If its deadcalm, I land neutral, if theres anycrosswind at all Iuse 12mm and if itsblowing hard, I go to 18mm spoilerons. This setup worksgreat. Of course withspoilerons on, there's aneed for a click or two of throttle above idle.

Anyone have advice there- flaps or not for harriers? I see some guys that harrier a lot using ele-> flap mixing but I haven't done that yet on this one.

If you absolutely MUST spend money on wheels, I think that a better investment is a Sullivan or other tailwheel bracket- so that you have a spring between the tailwheel and the Rudder servo. They always take a beating otherwise- I crashed a GP 40 size extra due to stripped rudder gearing once and have never done "hard" tailwheel mounts since. I think that between crosswind landings, and my tendency to let it roll and yank elevator on a windy day, the tailwheel sees a lot of shock loads.
cmoulder: I think that it is remarkable how nicely the tail lifts on this Extra. I just let it lift on its own and then gently add elevator when I want to get airborne. Looks great taking off that way. My other planes have needed generally "active" elevator once the tail lifts to keep from tripping over their mains. Next I want to do it all in reverse: land on the mains first and drop the tail 20 feet later. That always looks great when my buddy does it with his Cub. Wish me luck- heck, I've got a coupla spare props!

ok i'll try that, thanks

Off to Joe Nall tomorrow, hoping to hit venders row.

[8D]

it is remarkable how nicely the tail lifts on this Extra. I just let it lift on its own and then gently add elevator when I want to get airborne. Looks great taking off that way.

It helps to have a tiny bit of down trim. It's fun just to leisurely roll into the throttle and let the tail come up and break ground at about 1/2 throttle. Such a stark contrast to a lot of take-offs whereguys just gunit, yank the elevator and hope thatit leaps skyward somewhere downrange without veering into the pits.

I was able to pick up everything I needed today , except for the 5/16" nylon bolts for the canopy. Got a beautiful XOAR 14 x 4 prop, it's almost too nice to use...Got a Sullivan pull pull cable set. I'm ready to start building as soon as the 3152 servos get here. )

Bob- I agree- its fun AND pretty to do scaleish takeoffs. Not my old habit, but I'm trying to make it my new one. Its alsoa lot betterto be taking off level(er) if the engine quits, eh? BTW- Have youevermanaged to land on the mains and roll 20' before the tail hits yet? I'm wondering if its the nose high attitude when you slow it down that is making this tough for me- all of my clean landings are ~3 pointers.Probably justmy "new plane" jitters, but I'm having a hard time- maybe I'll up the airbrakes from 13-20mm &amp; see. Of course thehigh wing layout on the Cub probably makes it easier for my buddy- you can see the darn wheels better! (Oh, yeah he's a better pilot, too! That'll all have to be next weekend- we are flying off water both days this weekend and my Phoenix Extra (Phextra?) isn't due for such "carnage by the sea" abuse til NEXT year...!</p>

Racerchuck- FYI: I found 8-32 nylon bolts (not 5/16) went into the existing canopy blind nuts nicely, meaning a little "squeaky'. The blind nuts are 4mm dia by 0.7mm pitch which is close enough to the 8-32 diameter (0.164" dia) that it works. In fact, the 8-32 is only7 thousandths of an inch bigger than 5mm (0.157" dia) and the 4mm nut isalways a hair over 4mm and 8-32 bolts are always ahair under 0.164" making for a nice tight fit in most cases. The slight difference in pitch on the threads (32 tpi vs 0.7mm pitch) actually HELPS because it makes them turn in a little hard but they don't vibrate out. The 8-32 starts nicely and tightens up ina turn or two because the 8-32 pitch in metric would be 0.79mm vs 0.7. So for each thread engaged you get 0.0036")of interference in pitch added. This is good for short thread engagements- after about 8 threads you've actually wiped a whole thread out. OK, so maybe I do a little too much with threads at work....simply put, by dumb luckit works great- couldn't have designed it betterif Itried! Just go easy with the screwdriver the first coupla times when you put them in (torqueis high at first)or you can stab a hole in your fuse!! There are a few happy coincidences in the whole english/metric mess. Another one is the 5/16-18 vs M8x1.25- so close that you can squeak them together for lightly loaded applications like nylon bolts. Be careful doing this in metal, though.... the threads will pull out easier with the pitch mismatch.</p>

Ace Hardware has the 8-32 screws in nylon for flat screwdrivers. Next, I am looking for hex head nylon 8-32 to reduce the stabbing! I found the real 4mm x 0.7 nylonpan head screws at the hobby shop and will try them on the gear..... because those are loaded a bit moreI was a little nervous about the 8-32 trick- I can drill and lockwire those or just reef on them to keep em tight.. Another 0.3 oz saved for a buck or two!! Ihave had bad luck with the nylon screws in colder weather- but that's not til October....</p>

just posting here guys but if anyone offers me the right amount for my extra i'd sell it rtf minus receiver  </p>

with 0s .91 fx </p>

ds 821 servos </p>

 never been flown yet </p>

i finally  got to start working again doing side jobs and don't have the time and need the money </p>

 it's built right b/c cmoulder helped along with the rest of you guys </p>

wow wifey mad at me now she said no it's my baby hahahaha let me buy a couple more birds and then lets see what she has to say hahahaha good wife i have huh?

Or she just has it in for telelphone poles? Maybe she works for the company that replaces them and thinks you just need a bigger bird to beat the poles? HAHAHAHA
Glad to hear she may make you keep it. Its nice to have yer "chocolate puddin" now and then- i.e. something you really look forward to...

<p class="MsoNormal" style="margin: 0in 0in 0pt"><font face="Comic Sans MS" color="#000080" size="3">Lately, I&rsquo;ve only been able to get small segments of time to work on my extra. Progress is slow but moving forward.</font></p><p class="MsoNormal" style="margin: 0in 0in 0pt"><o><font face="Comic Sans MS" color="#000080" size="3"></font></o></p><p class="MsoNormal" style="margin: 0in 0in 0pt"><font face="Comic Sans MS" color="#000080" size="3">Picture 1 &ndash; This is how much I moved the wing tube on the right side of the fuselage. The left side pretty much stayed in the same place. </font></p><p class="MsoNormal" style="margin: 0in 0in 0pt"><o><font face="Comic Sans MS" color="#000080" size="3"></font></o></p><p class="MsoNormal" style="margin: 0in 0in 0pt"><font face="Comic Sans MS" color="#000080" size="3">Picture 2 - I used the 1/32&rdquo; plywood disk method for anchoring the hold down bolts in their new locations. I installed disk on the left side as well even though their position did not really change. </font></p><p class="MsoNormal" style="margin: 0in 0in 0pt"><o><font face="Comic Sans MS" color="#000080" size="3"></font></o></p><p class="MsoNormal" style="margin: 0in 0in 0pt"><font face="Comic Sans MS" color="#000080" size="3">Picture 3 &ndash; For convenience, I cut down the wing bolts to a 1&rdquo; length (under the flange). </font></p><p class="MsoNormal" style="margin: 0in 0in 0pt"><o><font face="Comic Sans MS" color="#000080" size="3"></font></o></p><p class="MsoNormal" style="margin: 0in 0in 0pt"><font face="Comic Sans MS" color="#000080" size="3">Pictures 4 thru 7 &ndash; Various stages of fitting and mounting the modified boxes for the elevator servos.</font></p>

min$2crash, contrary to what intuition might suggest, air brakes (spoilerons, actually) cause the nose of the plane to pitch upwhen deployedinstead of down, as I learned after setting up spoilerons on my Venus II last year.

Spoilerons do, however, cause the plane to "stick" very nicely and not bounce, but if the wing incidence is set properly (raising the wing TE), and with a tiny bit of down trim (or down elevator), wheel landings are quite do-able. Wheel landings are very difficult or impossible with spoilerons because of the nose pitch.

ALL planes will bounce if they are travelling faster than stall speed when landing. This is why - in order to keep the tail up and the main wheels down - a little down trim or a gentledown pressureon the stick is necessary. Obviously, easiest done when there is little or no wind, or a very steady light wind straight down the runway.

IMO, this plane lands fine without spoilerons, even with no wind. Just hold it off the ground until it has well and truly stalled and settles onto the runway on its own, and it won't bounce. I think what guys are doing is using too steep of an approach and not flattening the glide out long enough when approaching the runway. My Venus II has a LOT longer and faster glide than the Phoenix Extra, but I have learned to use a very long, shallow approach to put it on the runway where I want it, using throttle - NOT elevator - to tweak the glide path. Now that the Venus II is set up better - with fuel tank on CG, and CG back a little more - I no longer need spoilerons to land it.</p>

Rick, I don't quite understand the platforms for the rear servos, but there is no reason they shouldn't work, although they do add some weight to the tail.

Shortening the wing bolts is a good idea. Far more length than needed, and in all the time I've been flying mine I have never had the wing bolts loosen up at all, even with the hi-vibe 4 stroke....

OK, thanks, Bob. Now do you think this holds when I have the spoilerons mixed into down elevator? I have the spoilerons and flaps mixed into elevator so that at 1/2 throttle she stays level. The elevator mixes are typical- Flaps need up elevator and Spoilerons need down- just a tad, like 2-3mm. So I have that tad of down with spoilerons and a tad of up with flaps. So next, I'll try neutral when it isn't windy and the tad of down. I just hate down elevator when landing... feels wrong! My first attempts at landing this were on puffy tumbling crosswind days so Idid the spoilers so that I could land faster and avoid getting rolled by the crosswind gusts. The next time out it was even windier, so I upped the spoilerons and readjusted the elevator mix. I have now been flying with this cowpath setup for a gallon or so. Maybe its time to go back to neutral landings on a calm or down the runway breeze day.

I put my cowl on, hoping the extra frontal are would get it to climb in Knife Edge.The cowl andspinnerminus mybrassHigleyhub made it 3oz heavier in the nose, so I moved the battery back sothat the CGis at 125mm. Still no climb in KE but she holds it better now. I'm flying at 6# 14 oz dry, Saito 91 w/APC 16 x 4W prop- which climbs out of sight in hover, but won't punch out of hover. Do you think I should go further with the CG for KE or get more pitch in the prop? I picked up a 15 x 6 Zinger which this engine loved for juuuust hovering a 10# model, but that's 2 oz lighter than the APC which is probably going to put me back to 130mm. To rebalance or not to rebalance- that is the question (Hamlet).

This isn't a particularly good windy-day plane, as you have seen, and especially not good when the wind is turbulent, because it has a pretty low wing loading. However, this makes it good in almost every other way.

The amount of down elevator for the wheel landing is very little - just a breath, just as the plane touches down. This is why it is easier just to adjust the down trim when the plane is flying a smidge above stall speed so that it takes a tiny bit of stick to hold it level, and then simply relaxing the stick to neutral makes it stick on the runway with enough speed to keep the tail up. Also helps to use the "high" setting of idle-down as your "wheel landing" regime for Tx programming. Easier with a 4-stroke anyway because they like to keep pulling at low throttle... though I don't know about that with a 16x4.

I don't think this plane is capable of good KE climbing - let alone KE loops - because there just isn't enough side area. Mine also requires a lot of throttle just to maintain KE, and even then with quite a bit of yaw to hold it. But my CG seems about right at 125mm.

Bob, How's it going?

Time is getting one up on me and a lot of post get created inbetween my assembly progress. None the less, here is part of my post 703 that more or less explains why the boxes for the elevator.

I am surely not putting together the lightest Extra found on this thread. I am not trying to build a tank either. Soon, we will see how it turns out. However I do plan on cutting some out of the "BLOCK" that is the fairing between the Rudder/Verticle Stab and Horizontal Stab/Elevator to make up for the couple of grams I added.

Min$2crash,

I am amazed that you are able to have"UP" coupled with your flaps.

Actually, as cmoulder said, most planes tend to nose down in pitch with flaps down. If you've ever had a flying wing, think about how that worked when you dropped both elevons! Now, in case you're setting yours up and want a first crack for flaps &amp;spoilers- I am only at 13mm on flaps and the up elevator mixed in with that is just a mm or two, something like 10% mix with my linkage geometries.

Or were you surprised I could program it? That takes a bit of trial and error!!!! I have yet to see a perfectly clear programming manual for a radio when it comes to flaperons and spoilerons- always double check what they said should do what mix!!!!!

Just to clarify, I mentioned only that spoilerons cause the nose to pitch up, converse to what intuition would suggest, because flaperons also cause the nose to pitch up and require some down trim to compensate, as Rich alluded to.

I do not use any elevator mix for spoilerons with the Venus. Spoilerons were used for landing only, so I just let it descend with a nose-high attitude, using throttle to tweak the glide path, and a bit more than normal elevator to flare.

I have used flaps (not flaperons) with sailplanes and on a couple of other scale planes with flaps (again, inboard flaps, not flaperons) and they require some down elevator trim.

However, it is my experience (I must stress IMHO because I don't have a wealth of experience like many longtime RCU'ers) that flaperons are not a good idea. Yes, they slow the plane down, but they also create wash-in at the wing tips, which is an open invitation to a low, slow (and disastrous) tip stall when landing. This why real flaps are at the root of the wing, because it is desirable for the wing to stall from the root out when landing. When a sailplane is set up with Crow (aka Butterfly), the flaps are down and the ailerons go up a bit (aka Reflex) to keep the tips from stalling, with a lot of down elevator mix. If you want to really slow a plane down safely, this is the way to go, but you have to have separate flaps to do it.

</p>

<div style="margin: 0in 0in 0pt"><font color="#000080">Min2,</font></div><div style="margin: 0in 0in 0pt"><font color="#000080"> I was surprised that you needed &ldquo;up&rdquo; mixed in with flaps. I have a &ldquo;Wild Stik&rdquo; maybe you have seen the video I posted a couple pages back. Anyway, I play with the flaps on that thing quite a bit. Anyway, it takes a ton of down to keep the thing from standing on its tail with the flaps down. But, it has flaps and not flaperons.</font></div><div style="margin: 0in 0in 0pt"></div><div style="margin: 0in 0in 0pt"><font color="#000080">I also have &ldquo;airbrakes&rdquo; or &ldquo;crow set up on the thing. That is were the flaps go down and both ailerons go up. <span style="color: #339966">(I did not notice Bob had already described "Crow" till after I wrote this).</span> That takes a ton of down as well.

By the way, that plane does not need flaps in any way, shape, or form but they are sure fun to play with. Talking about STOL....This thing will do it.</font></div><div style="margin: 0in 0in 0pt"></div><div style="margin: 0in 0in 0pt"><font color="#000080">Bob,</font></div><div style="margin: 0in 0in 0pt"><font color="#000080"> I have heard about the tip stalling tendencies using flaperons before. It makes perfectly good sense to me that they could cause a problem. You can also run out of servo travel and/or bind stuff up if you are not carefull with the set-up. I figured I would play with them some on this Extra in order to get some first hand experience. Need I say that I will start with a little altitude before I ever put it on the ground that way. </font></div><div style="margin: 0in 0in 0pt"></div><div style="margin: 0in 0in 0pt"></div><div style="margin: 0in 0in 0pt"><font color="#000080">More on my Extra&rsquo;s progress.....</font></div><div style="margin: 0in 0in 0pt"></div><div style="margin: 0in 0in 0pt"><font color="#000080">I relocated my rudder servo with the intent of shifting weight more to the rear. This will also help a little with getting the wing bolts in and out. Earlier in this thread someone else did this as well. </font></div><div style="margin: 0in 0in 0pt"></div><div style="margin: 0in 0in 0pt"><font color="#000080">I fashioned the servo tray from some 1/8&rdquo; plywood. A piece of balsa is used to couple it with the stock tray to the rear and a 3/16 X 1/4 balsa with balsa triangle stock makes the rail for the front.</font></div><div style="margin: 0in 0in 0pt"></div><div style="margin: 0in 0in 0pt"><font color="#000080">With the elevator servos in, I was able to get a measurement for the centerlines of the linkages. Since the stab is not glued to the plane it&rsquo;s a lot easier to mark and drill and keep the holes strait. As the picture shows I used masking tape to mark the center and working from center I marked the location of the holes for the &ldquo;control horns&rdquo;</font></div>

OK, I think I used some confusing terms here. Cmoulder is talking flaps, I am talking about the flaperons that Idialed in to the ailerons, because I didn't kit-bash the ARFthat hard yet and have no separate flaps. I have "flaperoned"5 planes:3 fun fly's, anExtra and a home design- all needed a tad of up elevator when flapERONs were dropped cruising along at 1/2 throttle. My flaperon to elevator mixes have always needed up elevator to counter the tendency of dropping both flaperons in terms of pitch in order to hold altitude. I always do this mix incase I inadvertently throw the flap switch: it will still fly somewhat normally.
Dropping flaperons in level flight at 1/2 throttle drops the nose. It improves lift and reduces landing speed, but the increased drag below the wing CL also adjusts the pitch (nose down) and causes loss of altitude if I don't put in a little up elevator. I have always seen this effect. I have also advised people to ad-a-tad of up elevator mix on normal flaps- and it worked. Don't need a sudden pitch change if you bump the switch, IMHO. Personal choice, I guess. By the same token, spoilerONs tend to nose it up in my experience. If you don't put in down either with a mix, or by hand, it will just nose up more and more and could stall....

As far as crosswind/puff tolerance in landings, again subject to personal taste, if it is blowing like all getout, and I still choose to fly-
I will take a wingy plane (such as this Xtra at 6#13oz) and point the spoilerons up10-20 degrees for landing, but only if Ihave a mix dialed in to comp the "pitch up" tendency. I haven't heard or read about flaperons causing tip stalling, but I've lived it!! By that same token, spoilerons speed up the landing (power added) and cause the plane to be rock solid in puffs and crosswinds, because the landing speed is now closer to the windspeed/variation so that the plane doesn't juststall out of the sky if theres a puff: flat to nose down landings are more gust and crosswind tolerant.

<div style="margin: 0in 0in 0pt"><span style="font-family: Comic Sans MS"><font color="#000080">I am sure the black paint that Phoenix uses is fuel proof. But it sure did not appear to be sealing up the firewall and muffler area wood. I coated the area with 30 minute epoxy using one of those throw away &ldquo;acid brushes&rdquo;.</font></span></div><div style="margin: 0in 0in 0pt"><span style="font-family: Comic Sans MS"></span></div><div style="margin: 0in 0in 0pt"><span style="font-family: Comic Sans MS"><font color="#000080">Using my dremel tool with and a cutoff wheel, I cut about &frac14;&rdquo; off the machine screws that hold on the canopy. They are now just under 1/2&rdquo; long (not counting the bolt head). Just for grins, and because my scales were right there, I weighed the screws and washers before cutting and they were 12 grams (a little more than 3/8 of an ounce). After cutting and adding fuel tubing they were 10 grams. </font></span></div><div style="margin: 0in 0in 0pt"><span style="font-family: Comic Sans MS"></span></div><div style="margin: 0in 0in 0pt"><span style="font-family: Comic Sans MS"><font color="#000080">Speaking of the fuel tubing (used as a lock washer of sorts). The way these screws go into the fuse and hold the canopy, it is necessary to have large diameter fuel tubing that will bind on the inside of the hole the screws go into or use a long enough piece of smaller diameter tubing to come in contact with the t-nut when everything is tightened. In my case i used small diameter tubing and cut it about 5/16&rdquo; long.</font></span></div><div style="margin: 0in 0in 0pt"><span style="font-family: Comic Sans MS"></span></div><div style="margin: 0in 0in 0pt"><span style="font-family: Comic Sans MS"><font color="#000080">Another deal I am doing with the canopy is to seal/insulate the seams with black silicon sealer. The purpose of this is twofold. Each is as important to me as the other. Vibration and sound deadening is one. With this seal there will be a lot less noise. The other reason - is to keep air from moving in and out of this area. I am not too worried about fuel and oil residue making it in the fuse but I do not wish to have the fuselage exposed to varying air pressure on the inside because of this. I&rsquo;ll be sealing the mating surface of the wings in the same manner.</font></span></div><div style="margin: 0in 0in 0pt"><span style="font-family: Comic Sans MS"></span></div><div style="margin: 0in 0in 0pt"><span style="font-family: Comic Sans MS"><font color="#000080">In the pictures you can see that I have used (saran wrap) to cover the fuse area where the canopy comes in contact. I have put a thin bead of silicon all the way around the canopy including the cross beams because they have mating cross beams on the fuse (sound deadening). Last picture is with the canopy pressed down hard enough and long enough to get a good seal and then the screws are put in. It will set for at least 24 hours before I take it apart. Then I will let it set probably another 24 hours before I trim off the excess. </font></span></div>

Cmoulder- a light just went on when I reread your 5/18 post. When Iuse spoilerons, I am getting REFLEX on the ailerons, making tip stalls vanish. I always figured it was the higher landing speed that made it so stable in roll when spoilerons were on, but I'll bet the reflex is the lions share of it- rock solid that way in anycase.

RICKSTUUBZ- I also repainted the firewall- I never like dull paints for resistance to oil &amp; fuel but that paint Phoenix used made a great primer. I always like paintor white glue to seal the edge of the wraparound covering at the perimeter of a firewall so that it doesn't get oily and curl. I also blasted spray polyurethane in the entire tank/gear support area as best I could without too many sags and runs. That way, when I get a fuel leak (ALWAYS- just a matter of time!) the wood won't get soaked. Then Ijammed some paper towels in the "bilge" on either side of the tank floor.That way, if there's a slow leak, I can catch most of it in the towels. The spray paint covered almost everything in there pretty well- I wasn't about to spend 3 hrs with a brush. Your plane looks great, hope you get it in the air soon. I have done the silicone bead on seaplanes and floatplanes for obvious reasons. Never have gotten the stuff to stay for long unless I create some feature that isn't flat, i.e. holes or a groove to retain the silcone bead after it gets oily and tugged on. If you sealed the slanted "back of the pilot's seat" surface, you may want to put a thin film of silicone sprayor silicone grease so it slides in nice. Fishing stores have silicone grease for reels. Now that you've got her all pretty, be sure and use an exhaust diverter!

Can anyone tell me how far I should space a 2 stroke .91 away from the firewall? Specifically, an ASP 91 .

We've (my friend Jerry and I) have almost gotten mine ready to fly.

Chuck, it isn't super critical at all. So as long as the engine isn't scrunched up against the firewall or sticking way out on the ends of the mounting rails, it will be well within the range. Much more important is to make sure that the prop thrust washer lines up with the center of the fuse (after compensating for right thrust, of course) so that the flight dynamics aren't screwed up, and so that the spinner and the cowl line up.

I've been a bit distracted, working on another project.

Good reminder about the paper towels. No matter how well you pressure-test smoke systems they will still leak. I just did the cleanest, most conscientious, pressure-tested installation I have ever done and the &amp;#@*^#-ing thing still leaked a few drops.

One of these days I will get around to installing the .91 2c in the Phoenix, and now I know that smoke is actually a viable option.