The Horizontal Stabilizer

November 24, 2004

The empennage kit arrived the Wednesday before Thanksgiving; Jenni called me at work and told me it was there.  When I got home Jenni was looking at the boxes in the garage.  She wanted to open them so I told her she could open them up as I was driving home.

We inventoried everything when I got home and I studied the plans while waiting for 8PM to roll around. 

Why 8PM?  Here is why… The UPS guy claimed to have attempted delivery of the Cleveland Tools order. But Jenni was home all day and never once heard a knock or the doorbell (My guess, he never expected anyone to be home on a weekday and just put the delivery slip on the door.  We even had a note on the door that said we are home and to please ring the doorbell so I am calling BS on that one.  We had to go pick up the tools from the UPS Distribution Facility or wait until Monday for an attempt to redeliver.  NO WAY was I going to wait 4 ½ days until Monday to get started on this.

Here is a blurry picture of the Cleveland Tool Kit

We stopped at Home Depot after getting the tools at the UPS facility and picked up the bench grinder, a box organizer, a couple of bin’s and set out to start putting things together.  Jenni put all of the small parts and rivets in their appropriate bins so that it was all organized.  I was content with starting this in the morning but Jenni would not let that happen.  So I grabbed the rear spar and the rear spar reinforcements.

Jenni cleco’s the HS rear spar and spar reinforcements together.

Her sister Amanda even got into the building process.

Later on that night – I could not sleep so I went out into the garage and “broke” the edges of the rear spar reinforcements and made sure that there was a good fit to the rear spar.  The next step was to attach the elevator brackets and so I marked those all out and made sure that all were clecoed in their appropriate position.

Everything was match drilled and I was able to get a good feel for the Sioux Air Drill; very different using this little sucker than a big old Craftsman or Makita.

I had a 4 day weekend because of the holiday so I was able to concentrate on my learning curve and getting used to working with the tools in the build.  I am not a super mechanic but I can manage my way around a shop pretty well.  Van’s does an awesome job in explaining what needs to be done, but don’t expect them to tell you what to do every time.  After a few times you will notice that little reminders such as to de-burr the spars or ribs no longer appears.

November 25, 2004 – Thanksgiving

I machined down the HS710 and HS714 per the plans and made the appropriate bends in the parts. 

My method for getting the requisite 8 degree bend in them was to make sure that the parts were clamped to the corner of my workbench.  Using a Smart Level, either you can level out the part, the table or compensate for the error.  Since this was not my airplane building table and just my regular bench, I opted to just compensate. Taking that reading I was able to use two blocks of wood clamped to the part and then checked level. That was off even more so I wrote that number down.  I then made the bend and checked occasionally with the level.  When I got to the 8.4 degrees (8 degrees for the bend and .4 for the error), I removed the blocks and low and behold 8.2 was what the Smart Level was reading.  I double checked to make sure that the center point was still a .2 degree error then rechecked the bend.  Everything was inline and All I had to do was repeat that step 4 times (or so I thought).

Screw-up #1 When I was drilling the inboard ribs to the front spar to the reinforcements, I miscalculated the section of the rib flange that was to be removed and cut out something that would have held 2 HS710’s. Now what? I checked the plans, archives, email list, etc. and nothing really addressed this issue. Great! I was the first goof to make this mistake. Maybe I should quit now and build a shelf. That much I can manage. I tried matching stuff up and went ahead with the drilling of the forward spar, rib, reinforcement and managed to really screw up the rib. The hole was off and popped through the edge. Now I hated life. Here I was second guessing myself and really not too happy with ruining parts. In fact I was downright disappointed with myself. I happened to be reading posts to the RV list and someone brought up ruining a part and another poster gave me some words of wisdom without realizing it. He told the email list that he has spent more than his fair share of money on re-ordering parts and felt like he could have bought two airplanes. Made me smile, also encouraged me that I was not the first and likely not the last to screw up a part or two and have to order new ones.

November 28, 2004

I made amends with myself and continued on and worked on the rest of the drilling of the other side.  This actually looks like an airplane part now.

November 30, 2004

I humbly ordered the new parts from Van’s and was surprised to find out that $40 got me the three parts that I needed.  I ordered another HS710 with the new inboard rib and forward spar because the hole through it was a bit off.  I wanted it to be perfect for such a structural component.

December 2, 2004

Jenni called and said she got tubed by the FedEx guy.  Sick humor I know but I laughed as I realized that the replacement parts were here.

After the new parts arrived I tried it again and was much more satisfied with the results and pleased with how it turned out.  Now those ruined parts don my wall in the shop with the cutout from the Empennage box that says “Fragile: High Dollar Aircraft Parts”.  They serve as a reminder that mistakes will happen and that you must “measure twice and cut once”.

After redoing the parts I learned how to flute the ribs, got the front spar drilling centered “DNO” (dead nuts on) and had the skins fully drilled.  Now we had to take it all apart again and debur the parts, dimple and prime.  That was a priceless moment – telling the better half that all of that work was just to drill it all, now we get to take it apart and do more stuff to it. 

After priming, I hung the parts in the garage to dry.

I am currently using a rattle can primer.  It’s the Sherwin Williams 988 GBP self etching primer that other builders have used.  I am not so thrilled about the durability factor and I am likely going to switch to AKZO two part epoxy primer.

My first competed part.  My first official part that I made permanent was the center bearing.  Here you can see what it looks like after squeezing the rivets for it.  Woohoo!!

We riveted the HS skeleton together and then riveted on the skins.  We went the hard route and used the AN426 flush rivets all the way to the front of the leading edge and are much happier for it.  After the skins were on it was time to close out the HS.  The last rivets along the rear spar were easy because they were all AN3 and blind rivets.  AN4 rivets are a pain in the ass to squeeze.

Here is one side of the HS skin riveted…starting to look like airplane parts.

Jenni’s commentary on aircraft building.

Ahhh…Our first completed major piece!  Here we are with our completed Horizontal Stabilizer.

UPDATE:

I installed the AN3-5A bolts with the washers and AN365 nuts on the main elevator attach bearing on August 10, 2005 because I was needing a good torque wrench that measured in inch pounds.  Save yourself the time and do not get the one from Harbor Freight.  The ‘click’ is not at all noticeable at 25in/lbs and I did not trust that tool at all.  I picked up a Craftsman torque wrench at Sears for $68 and it works great.