Sunday, November 27, 2011
Unfortunately my attempt to drill holes for the Apex tiedown bars did not go well. The first one suffered from layout issues that made the holes off-center. Bottom line is that a ruler plus marking pen is simply inadequate for accuracy. Looking online, it appears that others pioneered this mistake well in advance of today.
On the second bar, I was able to produce a unique piece of art. The work scooted under the edge if the stop on the saw. Result: wrecked aluminum and broken tooth on the aluminum saw. Luckily the blade held together, so no amputations. Ordered a new blade, two new hunks of aluminum, and a beer.
BTW, for others building RVs, these apex plates can be ordered with the pain of tapping the hole already finished. See Cleaveland Tool's website.
Total Time: 3 hours
Monday, November 21, 2011
Sunday, November 20, 2011
Total Time: 7 hours
Thursday, November 17, 2011
First, I primed a bunch of nutplates. They are plain steel, so if anything ever needed priming in the Pacific Northwest, these nutplates would be at the top of the list. Note that the photo shows two types. I only used the flat (small) ones, but figured that I may as well prime some of each.
Then each center hole was drilled to 3/16" (instructions are very vague here), and the bottom of each hole was deburred.
Next up was to create a template piece of metal to use for testing countersink depths. The aluminum test piece is the same thickness as the tank skins (0.032"), and dimpled for a #8 screw.
I started installing nutplates, one or two at a time, and riveted them in place. The nutplate will sever to center the countersink bit.
Set up my new single-fluke bit and gingerly drilled to the correct depth, testing with just the screw and also with the metal template to make certain that all is correct. Think that I need to go just a touch deeper; however want someone else to look at my work first. Easy to drill deeper, but not so easy if the holes are too deep...
Total Time: 2 hours
Wednesday, November 16, 2011
Building both wings at the same time, so overall progress will be faster due to efficiencies. Or at least that's the lie that I am telling myself.
Not much else to say, other than there are still lots of holes to work on!
Total Time: 1.5 hours
Saturday, November 12, 2011
Once out, I also opened up the many hardware bags of rivets, screws, and fittings. Tucked each of them away in a wall-storage bin with clear plastic drawers. Hopefully the parts organization is logical enough to find the parts when needed later.
And finally the first couple of nutplate rivet holes were countersunk.
Below are photos that are mostly for the records -- and that show the hand-etched serial numbers of each spar.
Total Time: 7 Hours
Wednesday, November 9, 2011
Well, "tonight" turned into three nights thanks to interruptions such as the family's Domain Controller crashing, a surprise launch of a new Amazon Web Services region, etc., etc. Nonetheless, the two photos below represent the tool. This puppy is slick, and initial tests indicate that I should save a ton of time on the wings. Just wish that I'd built it for the empennage ribs...
The base and wood immediately on top of the base are pine. All wood directly attached to the metal sidebars is maple from my scrap box. That maple was originally intended for new cabinets, but I know that you won't tell anyone!
Here's the bill of material, if you want to build your own:
- 1 ea. 2x6, cut to 18" long
- 1 ea. 2x4, cut to 10" long with an 11 degree undercut bevel on the "business end"
- 1 ea 1x1-1/2 maple (or any hardwood). I cut mine to 16" and it could be longer. Also thing that a 2x2 might be sturdier -- this handle takes a lot of abuse
- 1 ea 3" long block, made from the same maple stock. I used my biscuit jointer to insert a couple of wood biscuits and glue up a double-height block. Probably overkill, but I got to play with more toys that way.
- 1 ea. 3/16x1x3ft Weld steel flat bar, purchased at Lowes and cut into 2 ea 10" lengths. OK, cut into 12" lengths and then shortened to 10" when I screwed up alignment on 1/4" holes in one end.
- 2 ea. 1/4-20 x 2-1/2 bolts, also from Lowes Aircraft Supply. These are not aircraft grade bolts -- they just look like it.
- Washers and self-locking nuts for the bolts. I managed to purchase 1/4-20 bolts and 28-TPI nuts. Like I said, Lowes is not aircraft grade -- and mixing things up like they did was annoying. Fortunately I had nuts on hand.
Total Time: 2.5 hours (not counting going to Lowes to find a hunk of steel).
Tuesday, November 8, 2011
Sunday, November 6, 2011
This weekend was back at the project, and it was momentous! Finished work on the empennage, or at least as much work as can be done right now. Fiberglass tips and final assembly come at the end of the project.
Built trim tab #3, which came out great, assembled the elevators to the horizontal stab, and drilled an important hole in the elevator horns.
But not until a friend with a flying RV came over to eyeball my work. As per one of the photos below, alignment was off a bit once parts were assembled. Everyone told me that this is normal, although that seems odd in a CNC environment.
In order to drill that hole thru the center bearing, I used some punches from Harbor Freight that fit precisely into a wide variety of hole sizes. In this case it was a 1/4" pin that created the dimple to use as a starting point for the drill. After a #40 pilot hole, worked my way up thru a #30 to a 1/4" bit. The #30 intermediate hole included part of my finger, although I decided that assembling the finger at this time might be inconvenient.
I also realized how woefully dull my inherited drill bits are, so I ordered $300 worth of new cobalt drill indexes -- the first time in my life that I actually purchased all the bits new as a set. Probably should have done this years ago.
All parts now hanging on the garage wall, and it's time to start on the wings.
Total Time this weekend: 19 hours