Posts by Dave Berenholtz

Forward of the throttle I am putting six controls into the armrest. The two seat heaters, the pitot heat and oil heat and the two cooling fan switches. In other words this is my ‘heat’ area for the aircraft avionic controls.

First up I wanted the seat heater switches to be very close to the top of the armrest. This meant I needed to remove some foam and make a bed. Pretty easy.

I did a good job of making the switch mounts and epoxied them in place over night. That all worked out really well until I went to drill out for the switches. Too much force on the bracket and it failed at the wall. On to version 2.

Ignore the hot glue, this is a nice new bracket. A fraction wider so of course I had to cut into my simple layup, that should have been a few mm wider and deeper. Another over night cure.

Here’s my plan for this section. Pity that nice Ovation guitar knob didn’t work out . I’ll have to find something boring instead.

The bracket worked out except that it was a bit flimsy. I made the supporting piece you see above. It worked out about 1mm too high in the end but I have decided to leave it and round off a few corners. It is unnoticeable except that I just told you. I do want to finish and fly next year!

Oh and now you can see the interface box that I installed earlier.

On to the next bracket for the 4 remaining controls. This will sit just under the armrest and poke through. Its a weird shape as I’m going to rivet it to the existing armrest right angle piece as it just happens to be there. I could have ripped that out and made a single piece. Of course that would have needed other bits riveted too it so not much weight difference and probably another days work.

After quite some hours fiddling, especially the oil heater pot as it is so big under the plate and of course hard against the fuselage wall which needed a tweak.

Here we are done, except for a knob change. The switches are accessible but hardly protrude above the armrest as planned.

While not yet done you can see that armrest is busy!

Yes, I can put my arm down there and not notice all that stuff.

The unusual HF head install continues.

Yes its an ellipse, like the side windows. With this shape I have found that I can rest my arm on that armrest and not even notice the big hole. I’m very happy with this concept. All the radio buttons and the LCD screen, on/off switch and the volume dial are also very easy to access.

Of course it was never going to be easy and just a hole carved out. This was only two ply thick and I needed a lot more for strength. I don’t want the console breaking through in flight when I lean on it.

An extra six plies of glass when on at the back with flox corners.

This is now acceptably strong, even where the oval shape is thinnest. Mine you at that point the radio head is just touching giving significant strength again.

Here we are again at the ellipse opening but now well reinforced.

The next problem was that I could see quite a gap between the radio and the inner armrest. What if I dropped a pencil or pen in there and it fouled the throttle? The radio needed an inner jacket!

This inner case for the radio head took way too much time. Its not quite finished but the pic is to give you an idea. When the armrest slides in place nothing will be going past the ‘head’.

Here’s a rather busy armrest and there is more to come in front of the throttle. Six switches are in the process of being installed.

The HF radio I’m using doesn’t fit in the instrument panel. It is totally full, but the left hand side pilot arm rest has potential.

Most of this mess has to go into the install. The antenna tuner already has a place in the hell hole which I sorted out some time ago. The handsets won’t be used but the rest will soon live in the plane.

This is the third set of ‘ears’ I made as the beginning of the radio head mount.

Here’s the angle I’m working on. This head will mostly disappear into the armrest.

I then made a few more additions to those brackets. I think I only had to make two sets of these. Why do I keep doing multiples? If its not right, it goes in the bin.

Is this making more sense now?

The main body of the radio also needed a cover.

The other end needed a bracket too. Those holes in the mounts are for clickbonds so I can attach the parts to the side of the fuselage.

It turned out I needed more support for the heavy main body of the radio. Easy, just make another bracket and rivet it on. I used the clickbond for the head doing double duty for the body here.

This was during the processes of installing the clickbonds to get the parts mounted. I used hot glue, bits of wood, whatever was handy while the epoxy set. You can see the armrest area is filling up.

I later mounted an interface box. That’s so boring it was hardly worth a photo. It goes forward of the throttle and behind those cables. I’m sure we might see it in later shots.

It has long been a question as to where to put the headphone jacks.

For the rear (PAX) I’m making the bracket that holds the jacks also to hold up the armrest. I need just the two GA type jacks and I’m adding a power outlet for a ANR if its needed. So three holes and the armrest nutplate.

I use whatever is handy for a ‘clamp’ while epoxy sets.

As you can see the jacks are sunken and I think this idea works well. Its a very complex little plane and any place I can make it look simpler I am.

I’m doing a similar idea for the front seat. (Pilot) I am using part of the existing armrest holder. I did have to move a nutplate, I can’t imagine having thought of this a couple of years ago and making provision in that bracket. It was only this week I sorted out where the jacks could go!

This area is busy but well under my left arm as ‘free space’. I have the standard GA plugs, a LEMO plug for powered ANR headsets, like my Lightspeed Zulu’s and a power outlet for ANR if I need it later with something different.

Again we have this buried idea. I will have to get in there later and make the insides of the holes nice with micro. Yeah, later…

I have 3 double USB ports for this plane. Here I’m documenting the fitting of two of them, oh and a couple of other small jobs along the way.

I am getting to those now or never jobs. As I was working on this arm rest it was time to seal off the edges. Where the Klixon fuses will go I’d spent hours on preserving the foam in between the fuses. Now I cut it all out to make one tidy uniform slot. This is much better.

I did careful flox corners with a tiny dental bit and then added a two ply layup to the exposed edges.

Here we are all cleaned up. MUCH better.

This is where I’ve added a couple of click bonds to hold that ferry pump relay. I found this spot over the main fuel pumps. In fact I have the relay reversed now so the connections are easier to get to.

Space is precious! Of course the cover that goes over this then had to be thinned out slightly and a ply of BID added to that. These are the things that gobble up time.

I spent a lot of time sitting in the plane and thinking about where these USB ports are going to go. This one is inside the pilot seat back. The outlets will be usable by a passenger but it’s mainly power in case I put a camera on my headrest. This is looking likely.

This is the back of the pilot seat and I have the screw on cover to nicely secure the USB.

The second USB is going in the right side pilot arm rest. Wow was this a lot of work, and a lot of thinking. In this shot you can see the cutout square. That was after I removed the foam at the end of the armrest and did a 4 ply BID layup. That is why you can see a green colour in that area.

You can see the beginnings of the USB fitting as well. My idea is to glue aluminium to the back of the USB but clear of the screw holes.

With a tongue of metal it can then mate to a second piece that is epoxied in place to the side wall. Nut plates will facilitate fixing and removal. This is the second piece before gluing it on.

The previous piece needed a bit out of it for things to fit. I can see now that I am really prototyping. In a different world, the fuse holders arm rest holder and USB holder would all be the one piece of metal. You can see I’ve had to dig into the seat back a little to fit the USB brick. I really wanted it deep in that corner so it was well under my elbow.

Does it all make sense now?

Finally all we see in the cockpit armrest is the USB port entry. I like it. Note that I’ve also added a bit of micro to the ends of the armrest for a better fit. Will this ever end?

My pilot (PIC) oxygen system runs on aircraft power and has one of those 12v cigarette lighter adapters. I’m going to change this to a merit plug. Its a really standard fitting but much more reliable that the usual car setup.

To explain if you are a non pilot type …which makes me wonder why you are reading this blog?  PAX is the passenger, who is also the GIB. Thats the guy or gal in the back. PIC is the pilot in charge. Only one person has all the controls so thats the front seat person in this two seater plane. PPT is the push to talk button for transmitting on the radio.

Here’s the back side of the plug and the bracket I’ve made. For some dumb reason I put those lightening holes in before I realised what a great fitting this is that can double as an armrest holder. I still got the nutplate in a useful spot, just.

This is my set up where I put some epoxy on the fitting and side wall and secure it in place. Then just unscrew after the cure and with the help of the release tape the part comes off easily.

Job done here, I have my electrical 12v outlet (well 14v really) and a support for the arm rest to screw into.

I made a cutout in the armrest rather than it being proud. When not in use this will not get bumped by my passenger. The feature I also wanted was that I can remove the armrest without disturbing the electricals.

Doh! Those lightening holes I put in so early. Now I’m using one of them for the GIB PPT. It was only after I had the 12v outlet in place that I thought this would be my spot for the push to talk button if I could submerge it so it would not be pressed accidentally. Perfect!

If you fly with me, do not press the red button unless you want to talk to air traffic control!

For an old school compass I’m going the vertical compass card route, and its lighted as well. This sort of compass reads like a DG and what I call the right way around. If you have a whiskey compass in your plane you know exactly what I’m talking about.

The compass needs to be installed with non metallic fittings and be well away from the panel and ferrous metal. It was always going to be a challenge on my build. While you get a mounting ring with the unit it was never going to work so I had to design my own.

This is one of the attempts to get the thing straight and the holes lined up. I had three tries.  Oh and I took quite a while sourcing that aluminium angle too.  The hole saw I had from the nineties when I put an instrument in my glider panel. That’s the last time it was used.

It took another go to realise that I needed such a long tail on the mount to make it work. I wanted it out of line of sight of the window and it had to be partly above the longeron but clear of the canopy rail when it closed..

My mounting idea used a bit of C channel. It wasn’t quite thick enough so I riveted on another piece. Knowing I had to glue one face to the longeron I also made multiple holes for the epoxy to have ‘fingers’ for better adhesion. The green fitting is a rivnut that I later squeezed in place. Yeah not a pretty fitting, sorry.

Is this making sense yet? The little extrusion gets glued below the longeron and its face is meeting at the same  width to give a base. I set this up and let it cure over night.

After the cure I drilled a hole in the longeron for the second rivnut. I later glued this in place which gives me the two mounting points. All thats left is a trim of the compass mount.

I’ll use different screws and some foam packing. Here I’m showing off the nice shape which overall took WAY too long to design and make.

Simple right?

Here’s how it looks with the compass mounted.

Just a simple little job that took more than 10 days. Yes I did other stuff too but this was a real time soak. I have a few tweaks to finish it off, however….this is enough for the log!