Cabin heating System

What are the chances of being about .25″ out for fitting the exit hoses from the Heat Exchanger? Pretty high possibility hahaha.

I elected to go -10 hoses here to get a better oil flow. I’m using SpeedFlow 101-10 and a fitting that goes from -6 to -10 on the radiator. It was just a little above the armrest core but not above the top.

My fix was to cut some foam away, make a concave glass insert, clean it all up as you see in pic 2. Pic 3 and we have a fit.

A small job but typical for this part of my build.

Not quite a fit

Adjustments

Just makes it

I needed a cover for the trap door box in the left corner in that back. It is a pretty odd shape. I made it easy on myself for a change. I just covered the area in duct tape.

Then I wetted out a previous template size of 2 ply BID on foil. I covered the area, let it cure and then released the glass as you can see in pic 2.

Pic 3 is after a quick clean up and I now have a perfectly fitting cover that solves the intrusion in the corner issue.

Tape the shape

Glass the shape

Use the shape

Pic 1 is my side wall. I can confirm thats Art Deco.

Pic 2 and we are in place with lots of nut plates and other things I didn’t document. Like how the various cover pieces fit into each other to minimise the fasteners required. Isn’t this log long enough already? Lets just assume quite a few hours went into getting to pic 2.

Pic 3 is while I’m thinking about foot rests and a cover for the trap door in the left corner. I might get some rest for a minute or two…..

Pretty eh?

It fits

Surprisingly comfy

Who doesn’t like a good Art Deco curve? That’s how this is turning out. I’m just the fabricator. This design has a will of its own. It is driven by the ferry tank positioning so curves are king.

A few bobby pins and I had my foam in a great curve (Pic 1) Pic 2 and I have a ply of BID on the inside so the curve is now stable. Pic 3 and we have the outside done and peel plied. I did a layer of micro first, let it cure sanded it and then applied the wet glass on foil.

I’m always trying to improve my technique. I might be OK by the time the plane is finished.

Pins work well

Inside glassed

Outside peel plied and looking good

Pic 1 shows the completed ‘fuel samba line’ cover I think we can call it. It is a curved bit of foam glassed inside and out and fits nicely into the other covers which partially hold it.

I spent some time on this and made brackets with nut plates and fitted all these things over several days. If you have read this far you would have seen lots of shots of that procedure.

Pic 2 is showing the curve I’ve worked out for the top. I completely forgot about where the canopy tubes go but I may have gotten away with it. We will see.

Pic three shows that I also completely forgot to put mouse holes in for the ferry tank straps so had to spend an extra couple of hours doing a cut out, glassing the area with flox corners and then a post cure clean up. Hey its all done now so it is in the past.

Fuel system cover

Side wall

Opps… forgot the mouse hole!

Ahh now do you see my plan for the GIB heat outlet? Do you also see how the side duct becomes a part of the wall? Can you see how the trap door is in the way and I’ve cut out a bit to allow for this. A better designer would have seen that one a mile off.

I have my fixes and you can see in pic two how I’ve graduated the trap door and pipe area to make minimal impact on the overall thickness of the side wall. This determines how much room the GIB has so every little bit counts.

Pic 3 is quite a nice layup on the inside of the wall. No one is going to see it and it’s one of my better ones!

Fitting the outlet and trap door

Inside carving

Glassing the inside

Here we go. I used my foam template to get a pieces of foam oversized and glassed. Of course it was a bit of a job thinning out the piece first as all my remaining foam is thicker now. No pics needed of all that fun.

Pic 2 is more fitting and working out what to do around the trap door in the corner.

Pic 3 shows that I have just one side glassed so I can play with positioning internally. The idea is to get the side wall cavity as wide as it must be and not a millimeter more.

First foam piece glassed

A trial fit

Making a minimum gap

That crazy Andair valve! The extension only goes in one way and so does the value knob. It took me quite a while to get my head around this.

I made all sorts of marks on bits of tape in the end. I kept grabbing the valve and blowing through it to be 200% sure I had thing right.

I had bought only one linkage for the valve but on fitting found I needed two. I needed another 20 degrees of turn, so a new one had to come from England. Don’t ask how much this all cost!

Finally I realised that the only way to get what I wanted was to cut the extension rod, rotate it 90 degrees and rejoin it. I found some aluminium tube the right OD to fit the extension ID after some time. Getting roll pins was ‘crazy hard’. Most people in shops don’t even know what they are.

Pic 3 shows I have them in place and you might see that the extender rod is ‘rotated’. Trust me when I say it all works as I want it now. I bet my life on it.

Extender in place

A break and a reset

Correct orientation

Pic 1 might have been before the last log entry. Its just even more duct entry tweaking. There was a lot of little pieces to make it all work and still have the volume of flow area I wanted to maintain.

Pic 2 is more trap door tweaking. I had to move the securing screw and this shot also shows a bit of the glass work I did on the body of the unit.

Pic 3 is the first planning of the side wall. I just used a piece of foam. Finally you can see why I moved that duct. It was right where my left foot goes! Not great.

I now have a little bit more of a plan for this side section. To be honest I’ve had no idea how I was going to do a lot of this. It just become more obvious the further I get. This approach would not work well for an architect! However I am building an experimental plane and sometimes that means taking a leap into the unknown.

A retro look at duct tweaking

A fit

Now for that side wall

So here we go for re-positioning the new duct. I have it well to the left hand side just inboard of the Andair valve extension.

Well that was a minor issue. To go as far to the left as possible this meant a curve was needed in my new duct as you see in pic 1. That was a couple of cure cycles. If you have a close look at pic 2 you can see where the universal join exits the front seat hole. This just needed a little more room.

Pic 3 has my new duct in place. It goes right over where the valve selector plate screws has to go so thats why I went for nut plates. I am right next to the top outlet piece so thats as far as I could go. It worked out really well in the end as you will see. The duct later becomes part of the ‘side wall’.

This is all a reminder that I’m getting to the pointy end of making all these modifications fit into the back area. Its all new ground and I haven’t opened the plans for a couple of months now.

Of course it needed a dip

In place

Tidy eh?

Here we have the new hot air path for the duct. We are now exiting under the seat on the outside (or in the pics, at the bottom) rather that the more middle path. That hole had to be filled in.

This new path has to climb or cross over the expanding duct to rejoin its path forwards. Pic 3 gives a pretty good idea.

I had to make duct paths for the join and tape them in separate operations to make all this happen. That’s why I went the straight route the first time. Which blindsided me to the PAX or GIB space situation.

Nothing easy about this one. BUT its in the past now so I don’t care.

Pieces of duct

Joining in stages

A diverted path

Even more trap door work has been done but more to the point way down in that corner I have more ramps going on. You see this clearly in Pic 2.

Ah, now notice anything about Pic 3? YES! That middle section is where a whole duct used to be and that circle near the top where an inlet hole was. I have removed the complete duct ramp and filled in the hole. Boy that was a difficult and somewhat painful job, mostly done hanging over the side and half upside down.

Yes my beautiful functional duct system had not allowed for the GIB. It was in the way of the passenger and just had to get moved.

All that ramp work at the trap door is to now make the hot air move via a more convoluted path down to the rear of the seat, over that trap door, then to the other side of the expanding duct and soon actually hopping over that duct to finally rejoin it’s path to the front.

More transition work

Even more again

Notice anything?