One solution is installing Cowl Louvers and I ordered them with the kit, just in case (this case!). I drilled big holes at both ends of the slits.

I use the Dremel to open up the slits by cutting between the holes. I don’t wear a respirator that much and I’m not a Covid-nut, but trimming Carbon is probably a great time to wear one.

Maybe I also should wear one during filing Carbon, but I really don’t think they are very comfortable, so … there’s that.
Anyway, filing the slits as close as straight as possible.

The final step is using sandpaper an a stick of wood to finish of the edges of the slits. As you can see I already picked up some Carbon dust on my cheeks.

The Cowl Louvers are riveted to the carbon cowl with flush rivets. So besides drilling the rivet holes, they also need to be counter sunk.

Apart from the Cowl Louvers, I was also measuring the optional mufflers. However, the sound of the engine is great and the mufflers too big, so I dropped that option.

My face starts to look like a miner, but instead of soot it is carbon dust (probably just as bad). Finishing of the oil cooler air duct, the trick is too keep some distance between the air duct and the oil cooler. The last half inch is filled with a silicone strip that is also used for the baffles. This provides a flexible fitting.

I’m checking the distance between the air cooler and the air duct, to see if the clearance is big enough.

Time to continue with the Cowl Louvers. We attach them to the cowl with Cleco’s to prepare them for the riveting.

Because of the ‘flaps’ on the inside you can only use the cleco’s on the outside.

Since the edge distance is too big, we can’t use the squeezer. So we use the rivet gun and bucking bar. Careful around the bend ‘flaps’. Maybe it was better to bend them after riveting.

Yip it looks great.

I installed the silicone strips with small Aluminum strips that hold plate nuts. You can’t directly rivet silicone, it will tear easily. Also you don’t want to use nuts here close to the propeller. So plate nuts is the best solution. It also provides some maintainability advantages.

Time: 6 Hours, Rivets:  0/0  (2021-05-19)

Time: 6 Hours, Rivets:  0/0  (2021-05-22)

Video

The UL Power engine has two separate Air-Boxes. Now you could seal them to the top cowl, but I didn’t like that idea. So I decided to create my own Baffle containment. It adds a little weight, but it enables more control over the airflow.

While I was designing these two plates, I was wondering how I could shape them to ‘follow’ the top Cowl. The Flute pliers are the answer, it’s magic how they can bend and shape Aluminum plates.

Trimming the standard UL Power Air-Boxes needs to be done in small increments. Placing and removing the top cowl dozens of times and marking the Aluminum to trim.
Also take into account that an engine will shake in its rubbers when it started or stopped.

I decided to use Screws and Plate Nuts to attach the ‘Plenum’s to my Air Boxes. So after drilling the holes for the Screws and the rivets to fasten the Plate Nuts, I can start riveting them together.

It’s a nice fit and it enable me to remove them easily when I need to do maintenance. They are not entirely finished yet, I still need to make the connection to the air intake of the top and bottom cowl. There I do need Silicone strips to seal them to the Cowl eventually.

While working on the Baffles, the resin of the bottom cowl, the intersection fairings andthe wheel pants fairings was curing. It turns out you can buy pre-build intesection fairings. Of course they won’t fit, but at least they are close. Although my Cowl is different I still think they could be useful. However I found this out AFTER I created my own.

It took me two tries to get it right and it still needs a lot of work. I really like working with fiber glass and resin, but finishing them smoothly is an art I still haven’t mastered. Also working with fluids (resin) up side down is fighting against gravity. Oh well, probably airplanes ar just that: fighting gravity. In the end you always lose.

This is also the second time I created the Wheel Pants Fairings. The first time I made them too small. Also I decided to make them differently then stated on the Van’s drawings. That construction looks too hard and not easy for maintenance.

Last part is the final attachment (after several tries) of the air duct (nozzle) to the bottom cowl. It should be dry by now, so I can start finishing it up to make it smooth.

Removing the bottom cowl by yourself is do-able, but you have to be careful not to drop it.

Now I can remove the duct-tape that held the parts together during the drying process. In my first attempt I didn’t want to ‘fight gravity’, so I put the cowl up side down on the workbench while drying. Well that didn’t work out, apparently the ‘deformation’ when laying up side down is too much and it didn’t fit anymore. So you have to let it dry while attached to the Fuselage.

Time: 5 Hours, Rivets:  0/0  (2021-04-23)

Time: 5 Hours, Rivets:  0/0  (2021-04-24)

Time: 7 Hours, Rivets:  0/0  (2021-04-25)

Time: 5 Hours, Rivets:  0/0  (2021-04-27)

Time: 6 Hours, Rivets:  0/0  (2021-04-28)

Time: 6 Hours, Rivets:  0/0  (2021-04-29)

Time: 8 Hours, Rivets:  0/0  (2021-04-30)

Time: 5 Hours, Rivets: 20/1  (2021-05-01)

Video

There is an extra Cowl part delivered for the Air intake of the Oil Cooler. However it took some time before I figured out how to cut the Air Intake and the Bottom Cowl to make it fit. And of course I made a noob mistake working with carbon.

The ULPower engine is delivered with the Oil filter screwed into the engine. The installation kit also holds an Oil thermostat, that opens the flow to the Oil Cooler (if necessary). So first task is to remove the Oil Filter and install the thermostat.

The thermostat has two hose connectors, just as the Oil Cooler and the goal is to connect those with the hoses included. Since setups may vary, you have cut the hose and clamp the connectors to the hose yourself.

The Oil hoses have a steel braided sleeve and I tried the hand saw, but my results were not suitable for getting the connectors installed after sawing. Here I use the Dremel and I have the hose taped with Duct-tape on both sides to prevent the sleeve from ‘unwinding’.

The connector consists of two parts, the outside nut and the inside connector. You have to push the hose in the Nut and then screw in the connector. After several tries I found that the best way is to:

• tape the hose end before cutting
• gently insert the hose end in the nut (with all the steel threads in the nut)
• push the nut with the hose against the workbench
• remove the tape
• twist the nut with a wrench to make the hose slide into the nut

For inserting the connector in the nut, apply some oil or grease, this makes it way easier to screw the connector in the nut.

According to the installation guide of ULPower, the hoses should be routed ‘around’ the propeller flange. I don’t see why I can’t directly connect them, but it’s probably a space issue. We have to be careful though, the hoses are routed very near to the arm with the electronic connections of the propeller.

I’m checking the (interactive) installation manual of ULPower, which is exceptionally well structured. I’m wandering what is worse, greasy fingers on a paper manual or an a tablet.

Making the last connection to the Oil Cooler and adding some protective rubber to prevent ‘chafing’ the hose.

Here’s the result. You can see the thermostat between the engine and the oil filter.

Next is the Air Intake for the Oil Cooler. As you can see the mold it came of, allows for many variations. At this point in time I’m still clueless on how to cut these parts.
At least it should not stick ‘over’ the nose of the Cowl. Also the forward top side fits pretty good on the bottom cowl.
A lot of trimming to do, so many opportunities to screw things up.

Here is the first ‘rough’ cut in the Bottom Cowl, which looks horrible and considering the costs of the Cowl made me shiver.

But I finally figured out that I need to cut a wedge type of hole into the Cowl to slide the Air Intake in. Note the wooden beam in the back, clamped to the cowl to keep the shape steady.

Now we have to center the parts and drill holes for cleco’s.

The fit is getting better and better and now I can use sand paper for the last edges. However this is also the point where I make a mistake. I did all the fitting while the Cowl rests on the workbench. Turns out it slightly deforms due to gravity. After gluing the parts together with resin, it didn’t fit the fuselage anymore. So I had to cut again and do it all over.

While the resin and carbon are drying, I work on the Air Boxes that guide the cooling air around the engine. Making these two fit the Cowl is a whole other story.

Time: 7 Hours, Rivets:  0/0  (2021-03-31)

Time: 8 Hours, Rivets:  0/0  (2021-04-04)

Time: 4 Hours, Rivets:  0/0  (2021-04-07)

Time: 6 Hours, Rivets:  0/0  (2021-04-14)

Time: 5 Hours, Rivets: 25/0  (2021-04-17)

Time: 5 Hours, Rivets:  0/0  (2021-04-18)

Time: 6 Hours, Rivets:  0/0  (2021-04-20)

Video

I want to have a close fit between the spinner and the cowl. However I found out later, that I was missing a part in the Engine package, which is the Reducer Flange.

This screwed up my tight fit as the thickness of the Reducer Flange is 3 mm, so the gap between the Cowl and Spinner is now 3 mm larger than I planned. Not a big problem, but still something I don’t like.

To prevent the spinner from being scratched, I only use it to measure and create a MDF template that I can use to attache the Cowl for trimming. Fortunately the spinner was transported to me from New Zealand on a ‘plate’ that can be transformed to a template.

Here you can see the template up close. On the Van’s RV models, the cowl are not screwed together and to the fuselage, but they are attached with piano-hinges, to create an ‘invisible’ connection. The piano-hinges are riveted together with the firewall to the fuselage.

Now I can shift the Top Cowl all the way forward against the template. And you can see the cowl sticks a few inches over the firewall. Also there is no hole in the front of the cowl, hence the forward part is still too high.

I’m cutting the forward part of the cowl to make a ‘hole’ where the crank-shaft flange ca stick to. Turns out the hole must be much bigger, but with cutting, I’m always conservative. Especially with an expensive part as the Cowl, you can’t afford a mistake.

Now the front part of the Cowl can ‘sink’ over the axle to the correct position. We fasten the cowl to the template and fix it with clamps.

We trim the cowl in two stages. First we trim it to approximately one inch from the firewall. This is still ‘save’, but gives us the opportunity to mark it for final trimming.

We mark the forward fuselage skin exactly 2 inches from the front. This way we can attach the cowl and still see the markings.

Now we mark the same 2 inch on the cowl and ‘in theory’ that would make it flush with the fuselage. Again I keep a millimetre margin on the save side.

Turns out that carbon is hard on the Dremel disks and they wear really fast. But using sandpaper for the last inch works great. You have to be careful, because the sandpaper cuts into the carbon.

With the cowl fixed to the piano-hinges, I installed the spinner and the distance between the spinner and cowl is a tight fit.

I’m really proud on the result. Too bad I was missing a part, so this tight fit is not here to stay.

We use the same strategy with the bottom cowl. However we can’t fit it, because the sump is in the way. I have to cut a hole in the bottom of the cowl so we can fit it.

Also the gear legs ‘stick’ out forward of the firewall. I have to cut holes in the bottom edges to fit around the gear legs.

These don’t have to be very precise, there are Intersection Fairings that cover the area between the gear leg fairing and the bottom cowl.

Here you can see we made a cutout for the sump in the bottom. This hole needs to be enlarged and covered with the air-duct for the oil cooler.

Here is the result with both the Cowl and the Spinner (including the extra Flange). Also the Sump and oil cooler are sticking out and I’ve marked the oil door with tape.

Time: 7 Hours, Rivets:  0/0  (2021-03-06)

Time: 6 Hours, Rivets:  0/0  (2021-03-10)

Time: 7 Hours, Rivets: 40/0  (2021-03-14)

Time: 6 Hours, Rivets: 30/0  (2021-03-17)

Time: 7 Hours, Rivets: 12/0  (2021-03-21)

Time: 5 Hours, Rivets: 41/6  (2021-03-24)

Time: 7 Hours, Rivets:  0/0  (2021-03-28)

Video

I’m going for a mat black and orange theme on the inside that matches the colors I choose for the interior. This combo is similar to the metallic paint I choose for the outside.

Next job is the Engine Mount. I use the ‘standard’ Lycoming Engine Mount with dynafocal attachment. This will later hold the extension mount I need for my UL Power 520iSA.
I have also installed the Firewall bulkheads for the Fuel and Return lines.

I don’t use the ‘standard’ Facet full pump, but two Bosch Fuel Pumps. However I already installed the Firewall doubler for the Facet pump including the nutplates. The bottom left nutplate will be sealed with Tank Sealant and a bolt. The top right nutplate is reused as the bulkhead for the Throttle cable.

I picked up the extended Cowl, created by Ray Lawrence of Kaolin Aviation, at the UL Power factory in Belgium. Of course it’ll take another few months before it is fitted to the fuselage, however I felt the urge to see how it would look.
EPIC!
Patrick Denorme Managing Director of UL Power, proudly showed me the new endurance test facility for the new 520iST. It provides 10% more horse power, but more important it can do that at a lower rpm (2800).

The 520 runs sweet for almost 180 hours testing. The engine sounds great and I can’t wait for my 520 to make first engine start. Unfortunately I have the normal aspirated version and not the Turbo. You can clearly see the Turbo Charger in the middle of the photo.

Attaching the Gear Legs was really hard. It turns out the powder coating is too thick and makes inserting the Gear Legs into the Engine Mount really hard.
In the end I succeeded, but in hind-sight I should have used some sand paper to remove the powder coat.

Time: 8 Hours, Rivets:  0/0  (2020-09-09)

Time: 4 Hours, Rivets:  0/0  (2020-09-11)

Time: 8 Hours, Rivets: 2212  (2020-09-12)

Time: 6 Hours, Rivets:  0/0  (2020-09-14)

Time: 5 Hours, Rivets:  0/0  (2020-09-15)