Monday, December 30, 2019

More Doors

The past few weeks have been dedicated to working on the door fit and the instrument panel.  I used my CNC to do some test cuts of the inserts for the instrument panel and found that there is a small error in the conversion from the Solidworks export DXF to the import process in Cambam (the GCode tool I use).  Turns out that everything I cut is just a bit over-sized.  So I took on the task of learning the Solidworks CAM solution.  It was a bit of a steep learning curve but I finally managed to get it working.  However....on my first test cut the controller board for my CNC failed.  I think it was in the USB connector but regardless it has become intermittent which is a problem.  Bottom line is I ordered some new parts for the CNC and will be making some upgrades to it soon.

Regarding the doors, I've been working on getting the seals to fit properly.  Once I felt they were about right I worked on the spacing between the doors and the cabin top.  Still lots of work to do but here is what I have so far.

This is the pilot side of the panel.  This is the insert that I cut that allowed me to discover the size difference in the DXF conversion process.  I had to do some significant edge sanding to get this one to fit properly.  I may have to do more since the paint will take up some room.  I'm considering having this anodized instead of painting but need to find a good local shop.

Passenger side door gap after inserting the foam spacer (seal), applying micro liberally on both sides of the foam, and then sanding the micro and foam spacer down to create an even transition.  In this picture the foam has not yet been removed.

Side view of same door as picture above.

In this picture the door on the right side of the photo still has the 1/8" rubber seal in place, the left side has been removed.  To open the door at this stage I had to use a razor knife to cut through the seal all the way around the door.  Then I could get the door open but had to remove the seal from both the door and the cabin top.  Both proved to be harder than I would have liked.

In this picture you can see the seam between the cabin top and the fuselage.  I sanded and then filled the small gap with micro/epoxy filler.

The door gap came out pretty nice by using some 1/8" rubber gasket material.  If I were going to do it again I don't think I would use the same stuff since it was a real bugger to remove.  The sticky side was up against the door and the plain rubber side was against the cabin top.  Turns out that epoxy loves that plain rubber and stuck like crazy.  I had to actually sand the gasket material off of the cabin side.  

Tuesday, December 10, 2019

Preping for last skin riveting

Much of my time recently has been focused on getting tasks complete that will allow me to rivet the forward top skin to the fuselage.  This skin is the last skin and major riveting job on the airplane!  I think I'm about there.

One task that is not shown below in pictures is some time I spent (on a nice sunny day) sanding and forming both doors for an 1/8" gap around the perimeter.  This gap will be filled with some 1/8" thick high density foam and then a layer of epoxy/micro will be added to both sides to make a nice consistent and even door to cabin top transition (after lots of sanding.)

I installed and torqued the rudder pedals.  I also fabricated and installed the brake lines.  I used PTFE -4 stainless braided hose and I replaced the plastic Tee with an aluminum one.  Because my master cylinders are behind the pedals it was a little harder to find a routing that would not put excessive stress on any part of a hose or impede movement of the rudder pedals.

This is a picture of the back side of the pedals.  You will notice that in the lower ports I used 90 degree fittings and the upper ports I used nipples with the 90 degree fitting on the hose.  No particular reason other than that I had the fittings available and I was hoping this would allow for more room for the hoses to pass each other during the swing.  I don't know that it made a difference but it didn't hurt anything either.

See this pile of hoses?  Seen them before?  Well this is the entire fuel system I fabricated several months ago.  Turns out I used standard rubber lined hose which normally is just fine but if I ever wanted to use fuel with alcohol in it there is a potential for degradation of these hoses.  So, I rebuilt all of my fuel system hoses using PTFE hose.  Not only is it better for the long run but it is also a bit smaller in diameter which turned out to be an advantage.

One of the steps required before I rivet this top skin on was cutting out holes for the vent fans.  Well, I decided to go with the bigger fans on the 10 so these holes are cut to fit a 120 mm fan.
The center support strut is now installed so I took this picture so I can contemplate wire routing to the overhead console.

I installed the top skin and the panel frame so that I could test fit the VPX/Fuse location. All is well but I couldn't resist taking a picture while its all installed.

One more picture just because I was happy with the days work.

I thought I would throw this one in there as well.  Here are a few of the parts/templates that I have printed using my 3D printer.  I have been amazed at how useful it has been.  Here are two 3D prints of the GSU25 ADHRS, one GEA24 EMS control unit, and a couple of templates that I used for drilling various holes.  The avionics templates were very handy in determining mounting locations as well as drilling holes for nut plates on the sub-panels.

There were a few days when I didn't want to work in the garage so I started working on the FlyLED lighting system.  I purchased "The Works" kit from Paul while at Oshkosh this year and just now got around to soldering the kit together.  I have to say that while I don't consider myself much of an electrician I REALLY enjoyed putting this kit together.  Getting a nice solder joint is just as satisfying as a nice line of well set rivets.

I had to cut some openings in my wing tips and trim the boards to fit the openings.  Here is the left wingtip with the boards cleco'd in place before I had started doing any soldering of lighting components.