Tuesday, July 14, 2020

40A - Gear & Engine Mount (nose gear & wheel); 46A - Leg & Wheel Fairings (intersection and nose gear fairings); 43 - Engine Installation (mounted engine to fuselage!)

The engine has been mounted to the fuselage!  All other crap I did the past two weeks was incidental to this major milestone - and thanks to Ken B., the install went quite smoothly.  Prior to that, I had received the nose gear leg and installed the nose gear and wheel, and did a bunch of composite work.  I'm really not a fan of fiberglass - almost a month of working on the 13 fairings for the wheels/legs and I'm still not quite finished. But, with the engine on, I'll be moving on to engine-related tasks for a while.  Here is what was accomplished during the past two weeks:

- installed nose gear leg and link assembly
- installed axle flange and nose fork, torqued the -24 nut until ~30lb of force felt per pulling with a fish scale (a little more than 26lb required, since will loosen over time); installed nose wheel
- removed intersection fairings and sanded/trimmed; floxed a lug to encase nut that attaches the training edge of each upper intersection fairing
- removed tape and excess flox from nut lugs; #27 drilled and #40 countersunk upper intersection fairings (attached to fuselage); removed main wheel fairings, and reattached halves with screws; drilled and deburred holes for nutplates in fairings; countersunk holes for nutplates
- figured out how to get fuselage into level flying position whilst having the nosewheel barely touching the ground; drew longitudinal center line on garage floor; marked standoff locations; aligned nose wheel fairing
- Cut slot in nose wheel fairing; aligned fairing in pitch; drilled bracket holes (magnet technique) and standoff pilot hole; tapped bracket holes; drilled standoff holes to just under 1” wide (will finish later, after - I received the proper screws to hold standoffs - was using shorter screws with washers for the initial fits); floxed brackets to nose wheel fairing rear
- Final drilled nose wheel fairing to brackets; installed nutplates to brackets; primed brackets; attached brackets to wheel fairing and attached to nose wheel; final fit of fairing (needed trimming to clear nose gear leg through the wheel’s range of motion)
- trimmed and aligned nose gear leg fairing; drilled nose gear leg fairing and hinge
- deburred, countersunk and riveted hinge halves to nose gear leg fairing; started initial fit of fairing (trimming, fitting, trimming again…)
- drilled #19 holes in fairing to attach to nose gear leg; attached nutplates to nose gear leg; final-trimmed fairing
- installed last oil fitting; cleaned and prepped workshop to install engine; installed engine onto dynafocal mount (w/ Ken B.!)

Floxed intersection fairings, installed on fuselage and wheel pants, and then removed them to trim:

Nose gear installation:


Installed nose gear fork, and torqued large castle nut such that the pull at the wheel axle would be approx. 26 lbs of force using a fish scale.  I got about 30-ish lbs, which will work itself in over time: 


Raised main wheels off the ground, to level airplane in roll and pitch:


Floxed a lug to encapsulate a nut on each upper intersection fairing:


Nose wheel, installed:


Fuselage level in pitch (i.e., flight attitude):


A pic showing the use of the engine hoist to do the heavy lifting:


Drew centerline on floor using plumb bobs and a straight edge - this was crucial in aligning the nose wheel fairing:


Used the round magnet trick to localize holes in the rear nose wheel fairing brackets - one side is taped...


... and the other side shows where the magnets adhered to the outside of the opaque fairings. I forgot to show that plastic washers were used (taped in place) to locate the center area to drill once the outside magnets were removed.  Drill one hole, cleco, move to the other side, and go back-and-forth until all 8 holes are drilled:


Initial trim of the front nose wheel fairing:


Initial fit of the two nose wheel fairing halves:


Initial drilling of bracket holes and standoff pilot hole:


Near-final trimming of wheel hole:


Brackets were floxed and 1" hole for the stand-offs was upsized from the 1/4" pilot hole:


Cut piece from front fairing was trimmed and riveted to rear fairing:


Nutplate holes were drilled in brackets using a proper nutplate jig:


Nutplates were attached, and brackets were primed and final-screwed into rear fairing:


Final position of nose wheel fairings:


Checked for clearance as nose wheel was swung from side to side (had to remove, trim, and recheck multiple times!):


Nose gear leg fairing, hinges drilled:


Nose gear leg fairing, nearly complete:


Now to the engine - that's a lot of weight (and expense) on one hook!


There are four bolts, and you should install the right top first (snug the nut almost completely), left top second (snug the nut almost completely), then either of the bottom bolts third (whichever lines up the best).  There are some great tricks of the trade here.  On top of those tricks, use the hoist to help jiggle the entire fuselage up/down to get the holes in alignment.  Due to the dynafocal mount, the bottom holes are only in alignment once the top have been snugged tightly and evenly.  Also, insert the bottom durometers that go between the mount and the engine BEFORE you tighten the top nuts, or it will be difficult if not impossible to insert them afterward.  


Thanks very much, Ken B., for your help today!  Nice to have been able to share this milestone with you.


Final pic, before removing hoist:


Engine installed!


Another pic:


Proof I did it, FAA:



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