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Elevator (1.5 hrs)

Started by reviewing (again) entire section for Elevators (29 pages).   HIghlighted special instructions , unique tools, etc.  

Sect 9-2 at Step 1:  Started with separation of E1008A and B ribs.  Used bandsaw first, then grind edges to lines.  Will deburr entire pieces soon.    Also jumped to Step 3 to separate and deburr the 3 Shear Clips while I was using bandsaw.

Edges not yet deburred.

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Horiz Stab (2 hrs)

Cont'd Step 4 on Sect 8-12:  Finished 3 more sides along Rear Spar.  Pleased with straightness and no waviness.    

Squeezing last few 426  3-4  flush rivets along Rear Spar.

Removed H.S. from four cradles, and rotated into "flat" position onto carpet over work tables.

Finally riveted center two Nose Ribs, including 5 (x2) rivets to Front Spar  using 470 rivets 4-7 and 4-8.

Needed the Offset cup rivet set tool in the rivet gun to reach these.   Required increasing pressure several clicks -- seems offset absorbs considerable energy.

Done with Sect 8 !   On to Elevators in Sect 9....

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Horiz Stab (3.5 hrs)

Sect 8-12 ( and 13 map).   Riveted remaining Inspar Ribs, including ends with  Nose Ribs.

before finishing end ribs....

Step 3:  Added Rear Spar.    Blind riveted spar to inner ribs, and riveted using 470 Universal heads into end ribs and 2 center ribs.

Step 4:  Did first 1/4 along Rear Spar at skin to flange rivet line (bottom left skin).  These go quickly with easy access while using squeezer.

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Horiz Stab (1.5 hrs)

Sect 8-12 (& page 13 is a map of rivets lengths),  Continued Step 2:  Finished riveting Top side to Inspar Ribs - except each end ( I plan to use rivet squeezer for those).  Partially done with bottom side.

I'd work longer, but it's time to go flying !   My wife and I taking turns this afternoon flying our club's C172.

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Horiz Stab (2.0 hrs)

Continued riveting "up to Stringers" (ie vertical lines near center).   Then riveted along Stringers (ie horizontally).   Then, per instructions, finish riveting to the remainder of Inspar Ribs...ie all remaining.

Fewer and fewer clecos.   Mostly done in center region...

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Horiz Stab (1.5 hrs)

Step 2 Sect 8-12:  Continued riveting along Rib flanges at inner sub-assembly...up to the Stringers as specified in instructions.    This area is kinda challenging since reaching with bucking bar is mostly blind; or by feel....since space and sightline is constrained by Stringers.

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Horiz Stab (5.0 hrs)

Cont'd with Sect 8-12 at Step 1:  Riveting along Front Spar flanges for all four sides (R & L, Top & Bott)  using page 8-13 "map" of rivet lengths (four different lengths).   Being really careful to insure smooth as possible for these flush rivets.   Looking great !

I did 208 rivets.  This is approximately 1.5 minutes per rivet ...some were quick (less than 20 seconds), but many took some attention to align bucking bar, insure all layers "compressed", and apply rivet tape.    Another builder shared with me his tip to use rivet tape on each flush rivet to limit sliding or movement of the rivet gun.  Seems to work for me, but does take more time.

For the last one of 4 sides,  I applied masking tape to the Spar to protect from bucking bar, AND to prevent dropping it into the nose rib area via the lightening holes.    Worked well...no scratches now (you can see minor scratches in opposite side at channel inside radius.   Plus less tension about having to retrieve the bucking bar if I let go at wrong time.

Prior side worked w/o tape led to some minor scratches into the Alclad layer.

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Horiz Stab (2.0 hrs)

Sect 8-11, Step 4:
Riveted rib and spar assembly into skins - starting with Nose Ribs to Front Spar.  Used LP4-3 blind rivets.  Added extensions to blind rivet tool:  simply pulled off the grey handle grips and slid on ~14" tubes made from old aluminum broom handle.  Added some duct tape (of course !) to "soften" the ends.   So much easier.   From barely able to squeeze handles inside skins to super easy access and leverage. Only wish I'd done this for first 3 rivets...9 others were quick and easy.   When done really simple to put grips back on, too.

3 blind rivets per Nose Ribs...difficult to get hands around grips to sufficiently squeeze...until extensions added.

Next Sect 8-12, installing flush rivets.   4 different lengths--- so must follow guide on page 8-13.   Began along front spar from center working outward.  Kinda challenging to hold bucking bar inside skins -- but getting them done one by one.  This will take awhile.

Self portrait in skins. Note flush rivets horizontally along spar.  It's a start!

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Horiz Stab (3.5 hrs)

Sect 8-11 continued Step 3:  Riveted 4 Nose Ribs into skins, 2 per side.    Challenging and awkward due to reach and positioning -- especially when needing to switch using left hand for some of the rivets.   My wife joined me to help hold skins "tight" to ribs for some locations...she was not only helpful but offered encouragement too.  (although she did slip in comment "Rosie the Riveter would've had this done already")

inside pic showing Nose Rib after riveting

Step 4:  Insert Front Spar / Inspar Rib Ass'ly into skins.    Yeah !  fits great and aligns perfectly.  Cleco'd Top and Bottom, Left and Right...took nearly hour just to check engagement of each cleco, etc.

Pic to show alignment...straight through nearly 114 inches.

Center section after inserting final Nose Ribs

test fit Rear Spar

I also test fit the Rear Spar...not ready to add yet, but fits really well also.  Critical to orient top from bottom, too.

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Horiz Stab  (1 hr)

Sect 8-11, Steps 1 & 2:   Set up 4 cradles (built earlier) to support LH and RH  #HS-901 skins.   Clampled each at proper location and orientation...for alignment  -- but chose NOT to screw down to table top yet.  (see pics).   Used 2 bar clamps and 2 woodworking clamps to secure each in position, but could still be shifted as needed.   When ready, can screw them temporarily to table top.

Cleco'd the 4 Nose Ribs into leading edge, 2 per skin.   Fit up was good.  Sweet !

View inside.   Kinda distorted, but shows nose ribs.

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Horiz Stab  (4 hrs )

Sect 8-9 Step 1 & 2:  Inboard Inspar Ribs riveted to Stringer and Web.   Finally, beginning to put it all together starting with this sub-assembly.

Sect 8-10:  Finished Steps 1 to 3.   Riveted Front Spar to Ribs.  (note:  two center Inspar Ribs are not yet riveted to Spar pending Nose Rib assembly at same time...next section).

I tried to use Main Squeezer for all the ribs, but several configs didn't allow proper reach &/or interfered with the rib's flanges.   I messed up one rivet, so after removing bad rivet, I switched to rivet gun/tungsten bucking bar...and it was easier.

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Horiz Stab (2.0 hrs)

Finished Step 4 on Sect 8-8:  Machine Countersunk #40 holes on 2 Stringers for dimples on skin (same as for 2 Spars).   Scuffed, cleaned with Acetone, then primed with #7720 Napa self etching Primer.   All 21 parts (Nose Ribs, Inspar Ribs, and Inboard Ribs) plus 2 Stringers.

I've refined my priming technique.  For these parts, only scuffed the areas that I've "worked" with tools or grinder, etc.   That leaves the untouched Alclad un-primed.  Only sprayed flanges and edges.
Saves time, weight, and $.     It seems unnecessary to scuff perfectly good Alclad surfaces, only to then prime.    Plus, experience with some pieces with a light coating of this self etching primer demonstrated to me how effectively it adheres to otherwise unprepped surfaces.  No peeling, even with moderate scratching.  Tough stuff !

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Horiz Stab (3.0 hrs)

Cont'd Dimple on RH skin top and bottom (still Step 1).  

Step 4:  Machine countersunk holes in Front Spar to accept dimpled skins.

Referencing Section 5 re: dimpled skins over surfaces to be countersunk -- the CS needs to be .007" deeper than normal to account for the dimpled skin.    I adjusted Micro Stop CS tool using test piece same .025" thick as skin with dimple to insure no gap at the skin to spar surface.   This required about 2 more "click's" to .009" extra overall.    I was tipped off about the extra depth needed per discussion today with Mike Lauritsen of Cleaveland Tools.  While I was investigating & ordering some special tools needed for Elevator build in Sect 9 coming soon,  he noted typically need .010" instead of .007" extra depth on the Micro Stop CS setting.   He reminded me to use a test piece to insure correct depth.  Thanks Mike for the insight !

Lots of holes along top and bottom of the spar, so takes considerable time..  Then, repeat on Rear Spar along top and bottom.    

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Horiz Stab  (2.5 hrs)

Sec 8-8, Step 1 cont'd:  Deburr LH and RH skins...all edges.   Chose to use large flat file to hand smooth edges, followed by 2" 3M scotchbrite wheel in air drill to finish.  Already completed Step 2 by marking holes NOT to be dimpled, which determined LH and RH skins.   Step 3:  Dimpled using C-Frame...completed Left skin.

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Horiz Stab (5 hrs)

Sec 8-6, Step 1:  Completed grinding radii to forward corners of Nose Rib flanges. Just like done for Vert Stab.    Fluted flanges of  ALL ribs to insure all holes straight line on flanges.  Certain ribs are easier to bend slightly the web between flange segments to align holes ( straightening out the web also).
Step 2:  Two Nose Ribs have rear flanges opened 10 degrees each.   And Two HS1004 Inspar Ribs have rear flange opened same 10 degrees, plus front flanges closed 12.4 degrees (with forward portion of web opened 2.5 degrees.    Checked results against each other to confirm equal (mated end to end to check "zero" out each other).

Sec 8-7, Steps 1-3:  Cleco'd Nose Ribs and Inspar Ribs to Front Spars (2 each w/ special 10 degree bends on end flanges).  These are in middle to align with tail cone later.

Steps 4-5:  Disassemble to deburr edges and holes (except few per instructions).   Dimpled all #40 holes on all Nose, Inspar, and Inboard Inspar Ribs.   Main Squeeze again used since can't use C-Frame.   Carefully checked depth to insure flush w/ skin (used scrap alum piece same thickness as skin, since skin not yet dimpled).

Sec 8-8, Step 1:  Start to prep 901 Skins.  Removed inside & outside blue film.  While some builders leave film on to protect during build, I decided to keep simpler and totally remove film - as I did previously for rudder.   Marked holes NOT to be dimpled on each edge (this determined which is right vs left skin...so critical !)   Thus clearly labeled skins as  Top vs Bottom, and Left vs Right.

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Horiz Stab (1.5)

Went flying today !   My wife and I targeted this date as best weather for the week ....62 deg F, and light wind with lot's of sunshine.  Really decent for March around here.   She flew first,  then we switched places for my turn.  Mostly practise T/O's and Landings, some 360 maneuvering.

Late in afternoon, finished building the 4 Cradles needed to support the Horiz Stab during assembly, per Sec 8-6, Step 4.

One of four,  pending mounting to table when needed.    

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Horiz Stab  (2.0 hrs)

Continued deburring per Sec 8-6.   Lots of edges !   Began to work ahead on Step 4: fabricate 4 cradles.  Using 1/2 MDF board, since cuts easier w/ jigsaw than 3/8 plywood, and costs less.  

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Horiz Stab (4.5 hrs)

Sec 8-5   Step 1:  Rivet Front Spar, Doubler, and Caps (2).    Requires 5 different rivet types/sizes, so needed to follow the diagram explicitly.    Again, Main Squeeze works great, although arms get tired after this many 1/8 in rivets.

My woodworking clamps make great stands for the Spar while riveting.  

 

Step 2:  Finished the Spar with 9 rivets on top flange at middle in Countersunk holes, and 9 more on bottom flange.

Sec 8-6,   Step1:  Deburr Nose Ribs, Inpar Ribs.  20 total.   All edges including lightening holes take some time.  Good time to listen to some comedy podcasts !

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Horiz Stab (3.5 hrs)

Sec 8-4, steps 2 - 7:   For Doubler on Front Spar, Final Drill all the #30 holes, then  C.S the 12 specified holes.   With top and bottom Caps cleco'd, also CS the middle 9 holes on flanges.

Disassembled all parts to deburr all the holes (lots !)  Buffed the parts with 3M Scotchbrite, then cleaned with Acetone.   I was actually able to prime outside, since temp was unusually warm  (74 degrees ) for early March in central Illinois.   Nice to not have to set up and use the spray booth.

Ready to re-assemble and rivet per Sec 8-5.

Prior disassembly to scuff and prime....

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Mar 7, Mon

Horiz Stab (3.5hrs)

Sect 8-4:  Started Front Spar build with deburring all edges, including lightening holes.  Clamped Spar Caps precisely, drilled #30 holes & deburred.  Re-assembled again with clecos so could drill #40 holes on flanges.  Time consuming process.   Per instructions, completed for top Cap, then repeated process for bottom Cap.

Note significant filings from using deburr tool on edges.