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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.