Posts by Dave Berenholtz

Date:  04-25-2024

Number of Hours:  6

Manual Reference:  23

Today I was determined to sort out the right side radiator. I thought I had it done but it was very close to the bottom cowl again somehow. Too close.

The mission was to see what was preventing it from sitting correctly and fix it once and for all time. After a bit of work I had it propped up with foam blocks where it needed to go. What followed was remaking the supports.

I had three goes at making this little support yesterday and it still wasn’t right. Today I moved the radiator into a clear position after undoing all but one of the attachments I had made so carefully in the previous attempts. I also remade this upper and lower bracket. Then put in nut plates.

I’m trying to set things up so you only need one tool to undo a support. That means not having a spanner on both sides, hence the nutplates,

On this one I moved the nutplate onto the more accessible side (what was I thinking) and put a hole in the corner in case I want to use a cable tie here.

I also had to shorten the middle support by a half inch and drill another hole. Not exactly the end of the world but it all takes time and patience.

This one was a bit weird. It is REALLY hard to access and only possible if the left radiator is out. I ended up putting a nutplate on the support and making this new one with the bends.

The radiator is now SUPER secure. Its like a rock, so mission accomplished.

The RHS I can now call secured. I’m still working on the LHS install.

 

 

Date:  04-21-2024

Number of Hours:  12

Manual Reference:  23

A few smaller jobs need to be documented. There are so many others that don’t make it to this blog,

Many hours just working things out, rethinking ideas, making orders, picking things up and perhaps redoing the way I had ‘things’. I did have to reroute the throttle cable recently to fit the LHS radiator. I got it done but it was a couple of sleepless nights trying to figure it out without a massive rebuild of the fittings.

The oil separator is quite a complex item to install. It has a number of parts that have to be mounted and plumbed into the crankcase vacuum outlet where a hose that vents overboard is usually placed.

After many days of thinking I worked out an easy way to mount the separator canister.

The backing plate was drilled out and fitted using the constant speed pitch ‘block off plate’ and its nuts. I’m surprised that it all went quite well.   …until I saw it wasn’t perfectly straight. <sigh> Well the engine won’t know and I just don’t want to spend another whole day getting it perfect when functionally there is zero difference. Perfection is still the enemy of good enough. …although I really would like it perfectly straight.

It looks pretty close, and as no one reads this blog, no one else will know its a few degrees out. Hmmm who am I talking to anyway?

On to the vacuum fitting that is a part of the system. I had to remove the screwed section, shorten the pipe it sits on and have it re-welded. Now it looks like it was born this way.

This is where I’ve decided it will sit. There is a hole now in the exhaust pipe at this point.

Another small job was to position the EGT sensors and drill a small hole in the exhaust for each of the four. I went for 3.25″ on each pipe down from the flange. A simple bit of tape with markings was my hi-tech measuring device.

Another little job was to position the air fuel ratio sensor. All this positioning has to be careful or I’ll never get the spark plugs out. Servicing some areas won’t be fun as it is VERY busy under the cowls but I’m trying not to make things worse where I can.

Here’s where it ended up and the ‘boss’ welded on.

 

Date:  04-22-2024

Number of Hours:  16

Manual Reference:  23

Here we go again, finally the LHS radiator arrived.

It came along with the overflow tank also finally done.

This took somewhere between 4 and 6 months to get sorted out. So it gets two pictures.

As you can see the weight came in at 5lbs 9.2ozs. A little more than the other side radiator which is slightly smaller.

I spent some time positioning it with blocks of foam trying to find the optimum spot. Clearance is everything.

On this side I will be able to make a grater gap between the inlet and the radiator face to better expand the air.

Having decided on the position I need clickbonds on the spar face to mount the unit. Of course I had to move a bunch of things like push rods and the roll trim assembly. I keep thinking I’m done with something and then have to move it later.

I now have the clickbonds in, the fire-protection restored and angled brackets made for the stainless steel support rods.

Here’s an overview of where it sits. I had a few issues with support brackets that were tack welded on. One weld failed and I lost a few more days getting more permanent welds done and then repositioning slightly the support location that was again hitting the cowl. I reversed a fitting in the end and got it happening.

The last few days were another clickbond on the wing edge which has made a really solid support. I didn’t really want to use these but it works super well. I need to tidy up the fittings and add nutplates but its on the way. Its quite solid now except for a little lateral movement. I’ll think of something.

 

 

Date:  04-07-2024

Number of Hours:  12

Manual Reference:  23

To cool the oil I need two hoses from the engine accessory case to the Oil cooler. In my case this is a heat exchanger using water to cool rather than an air cooled radiator. In any case two hoses need to go to ‘the cooler’.

It is an increasing problem as to where things go. I have an overview but when we get into the weeds its always tricky.

It is easy to forget where things go as you do the setup as there are many options and the differences are slight. With today’s camera phones and all that storage, I just take a lot of shots of everything.

The hoses end up here. At the engine end its a bit of a nightmare to attach and I can’t see what I’m doing, let alone get a camera in there. This end is a bit simpler except it has been challenging to get the right angled hose fittings to weave around the pipes and tight spaces.

I pressure tested the hoses to 1000psi as usual. One had a leak, a very slow leak but of course this unacceptable. It took the better part of a day to sort out after ordering new olives for the fittings which took a few days as well. The olives are the angled piece that bears down onto the hose to hold it tight.

I eventually got them all secured and leak free. Then some fire shield. The third hose in the pic I had a few goes at. This if for the expansion water tank. I still may have the length wrong as things are being moved AGAIN in that area.

At lease I have a couple of good oil hoses installed now.

 

Date:  04-04-2024

Number of Hours:  30

Manual Reference:  23

Having made a beautiful RHS radiator duct, of course its not going to work out now. I spent quite some time moving the radiator to accommodate the heat exchanger. Now I need a new duct to allow for the new position.

I covered the radiator in tape and selected a new piece of blue foam to make the ‘shape’.

I might add here I have been busy for a week making hoses and securing the throttle-body for real and a number of other jobs as well as a lot of planning for the next steps as well as progress on the oil hoses.

After some hours I got a shape that is beginning to fit. (you can see two oil hoses in approximate position)

A lot of refining got me a little closer. As this is my second try at this duct, or version 2.0, as it sounds better, I am working on the maximum size I can and still get the lower cowl on and off.

At this point you can see it is more refined. The old plug for version 1 of this duct is in the background. You can see with the radiator re-positioned where the air comes in is now in a new position, less central. I’ve also tried to get more volume into the duct to distribute the air a little better.

As before, its all about getting the air to enter via the armpit scoop and into the radiator. I still don’t know how I’m going to do the seal that has to still allow the removal and replacement of the cowl. I have a bit of an idea just to use foam seals but it will take quite some refinement.

At this point I’m getting closer. The ‘plug’ is contact glued to the tape and the intersections are refined down to 220 grit paper.

I use modeling clay to transition any gaps in the blue foam.

I just use cheap thin duct tape and cover the foam shape. There is no need for a release medium, its a one off shape.

Next up are just two plies of carbon fiber.

You can see here we have a bit of depth in the duct shape this time.

Getting the shape off and free always a bit of a process. This time I didn’t even try to preserve the plug, I just hacked it out. Very satisfying!

After a bit clean up and trim I have a pretty good fit onto the radiator.

I did the standard nut plate thing to hold the duct in place.

Here we are compared to Version 1. A much better fit and improved shape as well as the holding point for the screws integrated into the first 2 ply layup.

Final weight with the radiator is 5lbs 5 ozs. At least the duct is super light.

Of course I assembled it all on the plane only to find that one of the attachment points hits the cowl. Doh!!! I had to get a new piece of angle welded onto the radiator at unreasonable expense and the added cost of another day. Then the layup with more carbon.

After another two days and an easy clean up we have our new attachment point an inch or so down from the previous one which I have trimmed away. Of course I have done a new nutplate on the new tab.

All is well now. The bottom cowl clearances are good. The radiator fits. I can now start thinking about the LHS unit which I picked up yesterday from the welder. Here we go again.

 

 

 

 

 

 

 

 

 

Date:  03-22-2024

Number of Hours:  8

Manual Reference:  23

With the central bracket made this heat exchanger is still unsecured. It would move in flight and eventually the holding bracket would fail. However if it is held, immobile, with a fore and aft supports all should be well.

I spent a lot of yesterday making these two pieces to fit. While it is not exactly fancy, when tightened up it really holds its end up. Of course I spent the time to nutplate the back of the top bracket with maintenance in mind.

The prop end brackets were very challenging. This is my second attempt and I have gone for some 2024-T3 angle.

The back section was quite a fiddle to get in place.

Here they are roughed out. The fit is critical for this to work.

This was after many hours of work. The screws are countersunk with nutplates on the second fitting so you can still get a bolt into the heat exchanger without interference.

Finally I got it all screwed in place with various different fasteners. The black oil outlet fitting had to fit where things were very tight. I checked several times during all the placements.

This unit is now absolutely rock solid like it was welded in place. I need to get the radiators like this and I’m not sure how.

This was a VERY difficult install but like so many things on this build, it is in the past now. I can move on.

Here’s a bit of a look at how I’m planning to do these back hoses. All those fittings are very expensive and weigh more than I like. To me it’s a safety thing to get the best and do the best I can to ensure no leaks in flight. I will certainly be doing a lot of periodic checks on all these lines.

Date:  03-21-2024

Number of Hours:  50

Manual Reference:  23

After more work and endless fitting of the cowl I realised that this heat exchanger does not fit as I had hoped. So I refitted the RHS radiator to move it about an inch or so up towards the wing. This was to give more space for the water hoses that were not going to work out from where this heat exchanger was. That was a week’s work,,,

Then back to remounting that Laminova heat exchanger… again.

So I figured it would go here.

Just miss the throttle-body inlet with some fancy bends to get the angles I thought I wanted.

Lots of fitting with my prototype piece and I went to make the ‘final’ one. HA!

So I make another bracket. That was a fail, or lets call it another ‘prototype’ and back to seeing how to fit it again. By now I’d moved the radiator again and that was a mammoth job…again.

It looks clear in the pic here. The problem is that RHS corner was too near the cowl bottom. The rest of the unit is fine.

So I made another fancy bracket. Note this one has a bit of a bend at the left side attachments? then two bends after that. I seem to have a 2D brain where as a 3D brain is better for this stuff. So it takes a while.

Here’s my prototype again which I kept re-drilling and playing with and putting the bottom cowl on and off for.

So I got all excited and made another one to be the ‘final’ piece. After installing it and thinking I was OK I realised that the cowl wasn’t quite seated in its final position and this was yet another epic fail.

Even worse the local expert sheet metal guy walked pasted and said, “Is that commercial grade aluminium?”. “It will crack.” Well I am going to support it both ends, but he is right. He had a scrap of 6061-T6 although 2024 T3 would have been fine too. Anyway I’m getting better at roughing out this shape.

I got very busy for a couple more days and the one on the right is the final piece. The green thing (G10) is a spacer for the offset bend so I can screw the unit hard onto the bracket.

Its a funny shape but it works.

You get two pics here. Not because its interesting but because it took so long to get right!

Oh OK, three pics.

This is the unit in place. Its hard to see but I went to a LOT of trouble to position this so the oil connections could work. Notice the one at the front where you can just see the block hose fitting in place.

Here’s an overview of where it sits relative to everything else. The fun’s not over yet. This unit needs two more support brackets fore and aft. I want it rock solid to the engine which we all know shakes. I have concerns about all the stainless steel support rods I have on this thing. Cracking is something I will keep my eyes out for. Here I can use short angle brackets to get the job done so it might last.

I’m not going to document refitting the radiator here. The pics look almost the same as the first fitting, but it was many hours of work which I’ve included in this entries log.

 

 

 

 

 

 

 

Date:  03-08-2024

Number of Hours:  22

Manual Reference:  23

This is all about mounting the Laminova oil to water heat exchanger unit. The model is EC54 which is a double core and I spent months sending data and emails with then in the UK ensuring the unit was tweaked exactly for maximum efficiency for my application.

The Laminova weights in at a hefty 3lbs 15.8ozs. The oil cooler (cooled by air) that I was going to use weighs 5lbs 2.3ozs. So they are within 2.5ozs and that would not determine which to use.

It will go somewhere about here.

The idea is that cooled water comes AFTER the radiators have taken out heat and into this unit. The water flows through and exits at the aft end and then back into the engine. Oil from the engine in/out also goes to the unit and gets cooled.

The concept is that I am not introducing more air into the cowl, slowing it down through a radiator and then exiting the plane, slower than it went in so I would then have additional drag. No one likes that.

Of a couple of places ‘possible’ this is the only area that is going to work. I have to get two hoses in and two out so their ‘run’ is also very important. If I can keep the hose directions as straight as possible this also helps with the cooling efficiency.

With the bottom cowl on the unit is ‘almost’ clear. I’m good at the ends, top and sides, its just at the bottom I might have a problem.

After a LOT of thought and different ideas for mounting I think a simple bracket might just work. Using my CAD skills (cardboard aided design) I came up with this first draft shape.

Using the sump attachment point looks pretty secure.

It works as a start. I’m thinking I might be able to tie into the nearby throttle body for a second securing bracket.

Maybe something like this for the exits too. (Later I gave this a fail and thought of something else)

OK, it nearly worked. I’m just touching the bottom cowl. 75% marks when I need 100% for this exam.

There is plenty of room forward under the unit. After more head scratching I made a joggle using the big metal brake bender. I can slant the unit and just add spacers for the forward screws. Something like this will work.

It was still a bit tight on the bottom.

I found that if I slanted the bracket inboard I got much better clearance. I’ll have to reposition the sump boss holes, but thats easy and the first bracket is a prototype anyway. The good news is that this position is going to be doable and I have some fresh ideas for the hoses.

 

 

 

 

Date:  03-08-2024

Number of Hours:  35

Manual Reference:  23

The right side radiator has returned from the welder. It comes in at 5lbs 2.3ozs. The left side radiator is still MIA, with the core not yet delivered from the Queensland factory.

The welding is top notch.

Unfortunately many of the tabs are in the wrong place and that will have to be addressed.

Here’s the first shroud or duct that I made. This one just isn’t going to work out. I expected to have to make a second or heavily modify this one, even with just the final welding making a small shape change. I do have poof of concept.

After spending a week and thinking I had this radiator position sorted out, I was wrong. The exit AN-16 pipe from the second water pump is just too close to the radiator lower end. I am going to have to put nearly a weeks work aside and go again.

Where that upper arm is used to be back near the engine mount.

So I need a new tab about here… I had that tack welded on at the airfield and kept working on the new position. Now it was getting a lot harder.

All the arms I’d made no longer work and will need to be redone. On the plus side it looks like I will have the radiator an inch or so further back. This is good news for my feeder expansion duct as the more space between the opening and the rad face the better for spreading out the incoming air.

Yes I got a little excited and put nutplates on all the tabs. Harder to do up in the temporary sense but a better option long term given dropping those tiny nuts is just what you do.

Why didn’t I get the memo on this? I spent a couple of hours trying to get the bolt done up through this P-clamp. Yes lockwire makes it possible. Apparently its a standard thing to do, I just didn’t know it.

I had to add a second clickbond to secure a new bracket for the end radiator tab. That was a LOT of work. Retrofitting is never ideal, time wise.

It has been a real juggling match to get this radiator into the new position. It must not touch, the top cowl, the lower engine mount, the engine mount cross brace and particularly the bottom cowl. The bottom and top cowls came on and off 20 or more times, it was not fun. I got 3 out of 4 right. This exam requires a 100% mark for a pass. The radiator touches the cowl at the front, so I’m not there yet.

I ‘think’ I can lower the mid cross-brace P-Clamp by one 1/4 hole height and put in a new nutplate. This will raise the rad just a bit to hopefully clear the lower cowl. Then I’d need to make some new SS braces to secure it. Wish me luck.

 

 

Date:  02-22-2024

Number of Hours:  30

Manual Reference:  23

Time to connect the throttle in the cockpit to the throttle body at the engine. Another not so EZ (easy) little project.

I went through quite a process to get the length of the push pull cable I needed and then find someone who would make them. The process took some weeks but I thought I had the right one. The next issue was drilling a hole in the firewall and doing the cable run. Not so bad.

Meanwhile I found that because of the way the throttle was set up I needed a rod end rather than a simple clevis for attachment. I drove for nearly an hour to a place that has them for racing. I like the ones with the nylon insets so you never have to lube them. I paid the bucks, drove back to the hangar but for the life of me I couldn’t get it to fit. I was sure I had the specs correct!

Then I got a call. It was the rod end people to say they gave me a left hand thread by mistake and it wasn’t even a sealed one. The correct end as pictured above was a ten day wait and more money. I got to keep the old one if you ever need something with a left had thread. haha

Having positioned the cable roughly, I made an 2024 T3 aluminum bracket out of simple angle. I’m using click bonds for fasteners. My usual process is to make the fitting with holes then use that to position the little threaded bases with epoxy thickened with flox after I make notches in the bases to help key them in.

After they are fixed as above, I add two plies of BID glass to secure them. This is a super strong arrangement. A bit of grey paint follows so I can pretend I’m a tidy person.

All done and we have a working cable at one end with about a 60mm throw.

The next step is a bracket at the engine with the cable end pointing to where it needs to go. The attempt above is about the third try. This is roughly where it goes, or so I thought at the time.

Here I’ve drilled it out and things are solid so I can see where we are up to.

I just don’t think this will work. I can’t get enough bend in the very expensive so called flexible cable to get the clevis fitting anywhere near the throttle-body lever. I’m not happy with the angles.

Notice anything here? The attachment bracket is located on different screws now and the cable is a different colour. Yes during this process I ordered, and had made after several delays, another cable. So I got to pay twice for one item. This one is MUCH more flexible. I put it in, didn’t like the feel and went back to the first one. After a while I couldn’t get that working right. So again went for the brown one.

The newer brown cable in place at the cockpit end.. I spent some days putting this in and out. While the new cable is much better at tight bends, I realised that I might have issues with clearances in the engine bay when the left side radiator finally gets installed. I may have to put even more bend in the cable run. It is going to be tight.

I eventually made the bracket pretty and got rid of the screws in favour of some rivets.

That bit is in place with a relatively tight curve on the cable and it seems to work well. No jamming or loss of smoothness. I MIGHT have to bend the cable in a little to clear the radiator when it comes but I feel this is manageable.

The final piece of the puzzle is to dial in the geometry so the throttle position fully open and fully closed in the cockpit exactly matches the same thing in the throttle body.

Here I thought I had it right still using my Masonite templates. I was wrong. I didn’t know it and went on to make some aluminium versions as you see me doing above. They were still wrong. In the end, I went home and slept on it.

This is many hours later the next day and many iterations of a top plate. In the end I found I could alter the existing plate with a lot of grinding and it actually worked. I love it when you end up with an elegant solution after many tries at other configurations. You know when you have it right. …in the end.  I have painted the fitting above as it is steel and hence a little corrosion prevention is required.

You might say ..”Is that something the cat dragged in?” You would be wrong. My next problem was to make my clevis fitting work with new modified throttle bracket. I got very luckly. Our resident sheet meet worker, craftsman and LAME had a look and said, “You need a rod end here, not a clevis”. He was right as usual. I started wondering how many weeks and a couple of hours driving were in my future to get a simple rod end.

Instead he said, “I’ve got what you need.” This was the perfect fitting from an old under carriage door in some GA airplane in his spares collection. I’d never even seen one of these although it is a standard part used in certified airplanes. It is also exactly the same length and thread as the clevis I had. Unscrew one, screw in the new part. Perfect fit.

I cleaned it up and added some primer and paint without getting too excited. (yes I will add a locking fitting on the bottom later)

All dialed in I have a fantastic result. It is beautifully smooth and the geometry is correct. I do have adjustments if I need to fine tune this but I’m calling this one DONE.

Here’s the setup working.

Date:  02-12-2024

Number of Hours:  6

Manual Reference:  23

This is one of those jobs I rarely mention. I don’t generally count it in my accumulating hours either. It is one of those things that keep happening on every build ( I assume). Yes it took SIX HOURS! Yes it was 36C in the hangar today, it was hotter than outside which suggests that building a plane in a big tin shed is not that smart during summer. Then again I am very grateful to be in this hangar to finish my build.

That fuel line going down to the firewall is the new one I replaced today. The old one was beautiful. I had spent a long time on it getting it secured with hose clamps and routeing it to the firewall, supported every 6 inches or less, but it had to go.

Here’s where it ends up. I had to change the 45 degree fitting to this 90 degree. The problem I had to solve was the old hose interfering with the new radiator duct. I had a allowed for it but the run of the hose was just too close.

What I had to do was route the hose on the inside of the engine mount, not the outside as I had it. In the end, after swapping out the fittings on the same hose… well I was about an inch short.

So I made a new hose. Then I pressure tested it and the fitting proved to be no good. I went and had it replaced. Then there was a problem with the test gear, it just needed a hydraulic fluid top up as the reservoir was empty. This explains all the pumping I did. Opps. However I was getting a few bubbles in the old fitting which meant that was no good.

All replaced and check and checked again. I had a lot of trouble getting the old olive on the new hose. That’s OK, it went on eventually. I tested to 1000psi and it was good,

The hose was fitted OK. You see the two P-clamps in the picture. It took over one hour to put that AN3 bolt in and do it up. Those who have done the two P-clamp dance in an inaccessible place know the story. No one else would believe it.

I got this thing done. Two steps forward and one step back is progress in my world.

Tomorrow I refit the radiator and try to figure out how to seal it to the cowl. Tonight I have no idea how. Tomorrow is another day.