Saturday, September 27, 2014

31B-22 Fuel Pump Noise Filter

IMG 3672

Fuel Pump Noise Filter (Electrical)

The electrical system has a couple of capacitors on the 12V line to filter out some electrical noise.  This guy was a bit of a challenge to place, due to the narrow space (rear tunnel, below the baggage deck), but was conceptually simple.  It’s tie-wrapped to the wiring bundle and then glued to the lower skin with RTV (the red smear). 

 

In case you can’t tell, I did a lot of “little things” last week.  I’m trying to catch up on all of the little detours I’ve created for myself and get back to something more-or-less by the book.  Finally deciding to divide the trim wire harness allowed me to finish up the wiring, etc.  I’ve only got 2 or 3 pages of fittings & supports, and then go through with a bunch of tie wraps to make it look all nice.  

 

31B-04 installing Trim wires

Another successful case of Defeat being snatched from the grasp of Victory, but then Victory coming back for the win.  I divided the trim cable and installed micro-fit pins/connectors on the new ends for later assembly when I put on the tail cone.  I pulled the aft pitot line and routed it into the cockpit per plans and will run it back into the tail cone at the appropriate time. (note that the pitot line only goes back about 12” into the tail.)  This allowed me to run the trim lines into the WH-00046 connector, pictured below.

What is not pictured below is that I misplaced one of the pins into hole #32 instead of #30.  It only took a few hours, a phone call to Van’s and then watching a 2 min video from Steinair.com on how to use the pin insertion/removal tool.  I had used such a tool many, many, many years ago when I was an electronic engineer, but the memory escaped me until I saw the video.  15 more minutes of fiddling and I got the pin out of the wrong hole and back into the correct one.   In the process, I had to destroy the nice green shrink wrap you see below.  It is now ignominiously replaced with duct tape.  :-(

IMG 3667

WH-00046 after placement of Trim Wiring Harness

34-07 Canopy Latch Handle

I actually did this page a few weeks ago, but I didn’t like the result.  I didn’t do a good job holding things in place when I drilled the handle and the latch itself.  Although everything fit together, it was a little bit off and rattled.  I know that it would rattle in flight and drive me crazy, so I ordered new pieces from Van’s and repeated the assembly last week.

Here’s the jig I used to hold the handle and the latch in a vertical plane while I drilled with the press to make the pilot and then the larger holes prior to tapping.  Below, is the finished product.  Again, I’m not in any danger of wining a Lindy with this ship, but it’s functional and safe.

 

IMG 3663

Canopy Latch and Latch Handle in drilling jig


IMG 3664

Canopy Latch Handle

34-09 Riveting the Canopy

Whoo-Hoo!  This is one of the milestones that I’m really pleased to reach:  the canopy is riveted onto its frame, without a significant scratch or any fracture of any sort.  For some reason, I’ve been worried that it’s a fragile thing that needs to be protected by its frame.  It might be an unreasonable fear, but I’m glad it’s behind me regardless.

I’m going to stop canopy work here—the rest is fiberglass work for the front skirt, and I have no experience with fiberglass yet.  Since that’s a very cosmetically visible component, I’ll defer that until I get some education and practice. 

IMG 3657

 

IMG 3658

 

34-06 Side Skirts

These didn’t go on quite as smoothly as they could have.  I held each one in place, match drilled at one end, then match drilled at the other so they would be stable and hold in place with clecos.  Unfortunately, the stretch/curve of the fuselage meant that when I went from end to end with match drilling & clecoing, there was about 1 mm of excessive length compared to the placement of the original hole.  It looks smooth after being all riveted in place, but I know that it’s there.

 

IMG 3651

 Right Side Skirt

 

IMG 3652

Left Side Skirt with Lift Handle

Sunday, September 21, 2014

34-05 Fitting of Canopy

Sept 5, 2014:

This page was originally posted prior to completion, because I was just so pleased with the progress that I couldn’t wait.

 

IMG 3604

Initial fitting of the Canopy


The canopy has been placed for the first time!  I’m supposed to trim it to fit, and that’s got me a bit uptight, so I’m taking my time and letting everything settle in my mind before proceeding.  On the other hand, it’s a mile stone worth pre-publishing.  More to follow...

Sept 11, 2014

Here’s more.  I’ve been pretty busy this week, but haven’t finished fitting the canopy.  The Book calls out that I have 1/8” in gap from the front of the canopy to the edge of the instrument panel.  I’m not able to achieve that close of a fit with the canopy  frame clamped to the roll bar as per The Book.  If I release the clamps, it (the canopy) moves forward about 1/2” and is exactly where the book calls for it.  The Book says I can relax the clamps when I’m drilling the rear holes, but I’m not at that part yet, so I’m not confident that relaxing the clamps is a kosher maneuver.

 

 

Too much gap

Too much gap.

Note that the canopy edge is essentially overlying the top of the front bow.  There is, at most, 1/4” between the contact line and the edge of the canopy.  If I drill and rivet here, I’m pretty sure that I’ll break the leading edge of the canopy.

I decided to add all of the other stuff to the canopy attachment process, particularly the latching mechanism.   Specifically, I will remount the canopy with the latching mechanism in place and measure the front gap (1) with clamps in place, (2) with canopy latched closed, and (3) without any restraints.  I’ll take those numbers and fire off an email to support at Van’s and get back to you on this page with the results.

Personally, I’m hoping that I have acceptable measurements in condition #2, since that’s “final configuration” and I’ll be cleared to do final measurements and drilling.  (that is, as soon as this cold front passes and the temps warm back up into the 70’s or 80’s.)

 Sept 21, 2014

Slow and steady wins the race.

I got some advice & feedback from VAF, but nothing definitive.  I sent a couple of letters to Van’s but still ended up calling them to talk about it.  Joe, in Support, eventually opined that about 1/2” of plexiglass ahead of the forward bow would be enough to not have to worry about being too close to the edge.  The 1/4” gap specified between the canopy and the instrument panel appears to be un-important, as he had no real idea where it came from, whether it was a minimum or a maximum, etc.  He said the big concern was that the canopy wasn’t too close to the edge, as it would catch and prevent the canopy from opening.

I did discover that if I put the canopy on the frame, opened and closed it, the weight of the canopy itself did a nice job of helping to align itself sufficiently in the fore-aft direction.  I did take advantage of the permission to elongate the latch hole by its 1/8” allowance, but that was about it.

IMG 3639

Contact Line of Canopy to Front Bow

I had been using blue painter’s tape to prevent scratches, and in all of the previous test fittings, I had a very hard time seeing the contact line.  I used regular masking tape for the final trial fit and was pleasantly surprised at how well the contact line showed up.

IMG 3640

Holes drilled in front of Canopy & Front Bow


IMG 3641

1/8” gap from Canopy to Frame 

 

I got all of the holes drilled last night, including final drilling to #27.  It was a race, as that was the only day off when it was forecast to be warm.  Temperature in the garage was about 77 °F.  I used some modified bits and didn’t have a single crack, including one hole (L side, most forward hole) that ended up being right on the edge. 

IMG 3650

Acrylic Bits

These are the home made acrylic drill bits, #27 and #30.  I found this technique after much searching (and soul searching.)  Take the bit you want to modify (typically a dull one) and chuck it into a reversible hand drill.  Run it in reverse against your grinding wheel to make a nice, sharp point of about 60-65°.  These really end up being scraping bits instead of cutting.  They melt through acrylic, but really make a mess gouging / punching through thin aluminum, so you’ll have to do some cleaning up after drilling through both acrylic and aluminum sandwich. 

Saturday, September 20, 2014

34-07 Canopy Attach Angles & Canopy Latch

 

IMG 3644

 Open Canopy clecoed onto frame

Canopy in raised position

 

IMG 3646

Nick:  1st occupant of N76012!

 

IMG 3649

Nick helping with Canopy / Frame drilling

Thursday, September 18, 2014

32-03 Controls, small parts prep

While the canopy is ‘loose’ (e.g., not attached to the frame), I don’t want to be opening / closing it to get to things inside the cockpit.  I can’t do much more with the canopy until I hear back from Van’s re: the spacing issues alluded to on page 34-05.  Even if I had that info, I’m currently experiencing a nice cold snap in Ohio and don’t want to do any work on the canopy until it warms up (forecast temps in the 80’s this Saturday.)  I decided to do some small parts prep work on another section, and so turned my attention to chapter 32.  Nothing untoward happened on this page. :-)

IMG 3636

Control System Parts

34-12 Guide Blocks

IMG 3627

Nylon Guide Block

The canopy is centered and guided down with some nylon blocks that are mounted on the roll bar.  They required a bit of shaping and drilling.  The roll bar didn’t have any pre-located holes, so they were drilled and tapped as well.  

Step #6 is omitted at this time, as the canopy is not yet attached to the frame, so it is not possible to verify final fit.

9/27/14

I finished attaching the canopy a few days ago, and verified that there is no interference in the guide blocks.  The canopy comes down directly on the outside edge of the fuselage skins, and often needs a push (medial -> lateral) on both sides for it to properly seat with the lips slightly outside of the fuselage.  I’ll talk with some experienced builders about that.  I may have to reposition the guides  or something.

 

Thursday, September 11, 2014

34-11 Canopy Latch

On the other hand, this should have been simple and straightforward, but it wasn’t.  First of all, I had already installed the original latch when I built the roll bar but I needed to remove it as part of the retrofit for the new canopy closed switch.  Removing it was easy and I set it aside.  The replacement piece had two extra holes for the mounting of the switch.  I did all of the tapping and drilling without problem.  I attached the nylon guide piece before I noted (only in the retrofit instructions, not in The Book) that the tongue of the plate is to be bent forward 1/8”.  Fine.  I drilled out the rivets holding the guide piece and proceeded to bend the tongue back 1/8”, then re-riveted on the guide.  Did you catch that?  Specifically, did you catch the direction that I bent the tongue?  Back; not forward.  By the time I realized that, I had already done some work on the guide blocks that required the use of a #19 drill bit.  I didn’t check my drill and used that to remove the rivets again.  After I beat the tongue into the forward direction, I discovered that you can’t set #30 rivets in #19 holes.

Luckily, all was not lost.  To be precise, I had not lost the original latch plate.  I used the ruined one as a template, drilled the new holes, tapped one and shaped the other.  I had a spare piece of nylon as well, so I just re-carved a new one.  This time, all went as planed and the latch plate installed without problem.  Finally. I think.

IMG 3624

Blurry picture of Latch Plate and Latch Plate Block

IMG 3625

Latch Plate and Canopy-Closed micro switch


The wires for the eyeball light will be glued into place with tank sealant sometime soon.  (I’m making a list of all the places to use tank sealant and will do all those chores at one time.)

9/27/14

I finished installing the canopy & latch a few days ago and completed positioning the switch so that it activates properly when the canopy is closed and latched.

34-10 Canopy Latch Block

no muss, no fuss.  Drill, tap, thread.  Done.

 

IMG 3621

Canopy Latch Block

34-08 Guide Plate & Blocks

IMG 3617

Guide Block

IMG 3618Guide Plate 

Saturday, September 6, 2014

40-13 Eyeball Light

The eyeball light was easy to install since I put the bracket in a long time ago.  I just needed to attach the wires that were pulled last week.

2014 09 06 17 43 33

Eyeball Light

Friday, September 5, 2014

34-04 Canopy Attach Angles

IMG 3602

Canopy Attach Angles

The canopy attach angles are the thin angle pieces into which the sides of the canopy will eventually be riveted.  They needed to be fluted to match the curvature of the frame and then riveted in place.   I almost spent $25 on a tool (rivet fan) to put evenly spaced holes on these pieces, but realized later that they would not need to match up to any previously placed matching holes since I would be match drilling.  As a result of this realization, if I was off a few 32’s of an inch, it wouldn’t matter so I saved $25 and 5 days.  :0)

BTW, the blue tape is holding a piece of cardboard under the frame.  It turns out that regular cardboard is about 1/8” and it makes a great spacer.

34-03 mounting of canopy frame

The canopy frame was mounted without too much hassle.  As predicted by The Book, I did need to add some washers to prevent it from binding on the front fuselage when it pivots.

IMG 3599

Canopy Frame Installed on Fuselage

 

As you can tell, there’s a little bit of a clearance issue with the fuselage up on its stand, so I had to get it out side to do the first swing up/down.  

 

IMG 3600

Canopy in “closed” position

Here, the canopy is held down and firmly fixed with the addition of some wood blocks that were planed to the proper distance.  The blocks are held with the blue tape and the large ‘pony’ clamps hold the frame to the roll bar.   In the next step, I’ll figure out that I need to move the pony clamps to be inside the plane instead of sticking out in the breeze.

34-02 canopy parts prep

Well, it looks like I can’t count.  At least it looks like I can’t follow linear directions and go from chapter 31B to 32 to 33 to 34.  I decided to skip Flight Controls (32) and Miscellanea (33) and get started on the Canopy.  I won’t be able to do the rudder and elevator controls because there’s no tail cone to attach things to, so Flight Controls would only be a half-chapter anyway.  Miscellanea can be deferred as there don’t seem to be any strong dependancies.

On the other hand, there are multiple comments from Van’s and VAF that canopies should not be manipulated when they are cold, so I want to get it taken care of in September while it’s still warm.  Plus, there’s the very real realization that I’m afraid to work on the canopy and so I want to tackle it first and get it out of my system.

BTW, speaking of fearful projects, I re-filled the fuel tank and ran it for a while.  While I did get the expected leaks around the gascolator-to-return line (because I deliberately ignored the sealant), I didn’t see any perceptible leaks from the F-1204 fuel return line union, so I’m holding off on that project for a while as a “not required”.

Anyway, on to the fun!

IMG 3597

Canopy Frame and Misc Hardware

As usual, the first pages of a chapter are concerned with preparation of parts.  The front bow has been sanded flat, some angles have been drilled and (not shown) the gas struts were final drilled.