Didier

I made this from 1,5mm brown plate (CARF makes control horns from this stuff. Don’t know the name of it) You can make it from any material like carbon plate or glass fiber plate. I used countersunk screws
The inside of the canopy I glued flat carbon rod (last part of video) to make it stronger but also to make sure the rail systems runs smoother. It’s a little bit of “trial and error” due to fact the canopy thickness was not the same everywhere. Reworking is required here and there. Hope this helps.

darod07

Finally my Zero is ready for maiden.
Last thing I did is scale working canopy locking mechanism:



This is how all electronics is installed. All shifted as much us possible forward. Fuel tank is shifted from the center to the right. The gap on the left I use to put my fingers inside and push throttle pushrod to the side to choke my Saito. It works very well and I don't need choke bar or electric starter.
Maiden flight this Sunday...

mackone

Great work Darod
The install pics are a great help ....those receivers are always out of stock when I need them.
I like your choke idea as well.
cheers
Pete

darod07

My Zero had maiden flight today... All went pretty well but there was an issue with Saito's common problem- overheating. Above 3000 rpm temp. of top cylinder went up to 130 celsius and I had to reduce power to cool it down. Due to that I've made only 2 short flights. During second flight I tested retracts with clamshell doors. I was affraid that Electron retracts are not powerful enough to deal with heavy struts an spring load of clamshell doors but all worked just perfect and very scale like...
Now I have to check what can be done to improve cooling of Saito. Having baffles and fully opened cowl flaps I didn't expect such trouble with overheating. Any ideas what can be done or checked are welcome...
Here are some pictures taken by friend of mine during maiden flight:

BobH

My Feedback: (2)

Difficult to tell how good your baffling is. It should only air to PASS OVER THE CYLINDER and no place else. That means the baffle should be up against the sides of they cylinders.

darod07

There is 2-3mm gap around heat sink and abt 5mm gap around cylinders. Do you think it's to much?Baffles are placed slightly behind centerline of cylinders.

drorso

Congrats!
What is the final Take Off weight?
I saw somewhere an idea of creating a small fan (maybe 3D printed?) between the prop and the spinner back plate. Not sure where I saw it.

BobH

My Feedback: (2)

Yes that's too much room. No clearance between the baffle and the cylinder is best. That forces ALL the needed cooling air directly over the cylinder.

darod07

So I'll reduce clearance. Hopefuly that will help. Thanks for hint.

darod07

Thanks!
Dry weight is 15.5kg. TO with full fuel tank should be abt. 16.2kg. Seems a lot but it flyes great and landings aren't scarry...
Idea with additional fan is an option I consider. But I would affraid to install 3D printed.

BarracudaHockey

My Feedback: (11)

Nice pics!

jimkron

Looks like you have done all the things I've done.
1. Baffles just behind the centerline of cylinder (your gaps about like mine)
2. Open cowl flaps (you did more than me)
You have lots of oil coming out the bottom. It appear to be rich enough. Could you richen a bit more. Are you 15:1 on oil mixture?
What prop? What exhaust?
What are your rpms like on the ground and in to air? 6000 on ground for me, no more than 6700 after unloading in air.
Does the temp come down as you come off throttle? Sometimes I'll hit 240F at full throttle. Average running temp is around 220F
Was it a really hot day? I tend to run above my averages on hot days. 80 degrees and above.
Just some thoughts.

jim

darod07

Hi Jim,
That's what surprises me ...
I use 15:1 oil mixture, carb setting is H: 4 and L: 5.
Temps are dropping right after throttle comes off. During maiden flight ambient temp was abt 80F
Exhaust is self made ring muffler
Maybe prop (Biela 22x12 FW 190 type) is to heavy for Saito??? With this I can do only 5200 on the ground. I'm gonna check tomorrow 2 blade Foxy 24x12 to see how it will affect temp of top cylinder. I also ordered from Biela 22x12 WWII which others in this thread use. Hope this helps.

jimkron

My guru Ray English has tested the Biela FW "paddle" props and says the 22x12 is too big. Your numbers exactly. He suggests a 20x10 3 bladed. I'm getting 6200 rpm on ground...with the FW fan unit on the back of the spinner. I'm guessing it should be fine in the air. Unload to 6700. PROBLEM. Prop looks way to small if you want the cool scale look. Ray says it pulls like crazy. We'll see. I'm months away from maiden. Ground testing seems fine.

jim
EDIT: never mind...wrong forum. Thought I was posting on the FW 190 forum. Forget what I wrote above about paddle props. Jeez. I've got to stop drinking in the morning.
The Saito 84 in my Zero is running a 3 bladed Biela 22x12 with 6200 on the ground and 6700 unloaded in the air. It does have the Ray English modifications that give it a little more horse power...and it runs cooler.

darod07

I just tested my Saito with 2 blade Foxy 24x12...much better in the view of temps. With 3200rpm I get 201F on top cylinder. With 4500 it hits 220F, but this is on the ground. Should be better in the air.

Didier

Congratulations on you’re maiden flight!

I found the Biela 22x12 WW2 3 blade way to small for my 90. 6400 on ground and +7200 in air. Pitch is to small. Lots of revs, but no speed. I have a Ramoser now at 14,5” pitch. Way better speed. I can now fly half throttle with low RPM and good speed. If I go full power, it pulls like a train. My temps are around 135 degrees Celsius on cylinder 1 and 2. Measured on the back side of the cylinders. Just below the sparkplug. It runs really cool. Oil from the exhaust is clear, not even brown.

LtMash1A

Do you know what your carb settings are with this prop?

darod07

Thanks Didier!
I'm getting new prop tomorrow and will check how it performs with my Saito. You say not too much speed...It's ok for me. I'm not a speed freak, I prefer scale flying. With FW 190 Biela prop I was flying 1/3 of full throttle and for me speed of Zero was just right. I expect new prop slightly less performance, so maybe 1/2 of full throttle for scale flying. I'm planning to fly with new prop this weekend. Will let you know how it performs.

Didier

I really did not change my needles that much. Around 4 on high and 5 on low. I use a very good oil with a high flashpoint. I guess it helps in cooling and lubing the engine.

Didier

Where do you measure the temps on the cylinders?
If the prop suits you’re flying, that is great! 👍😃

darod07

I have temp sensor on the back of cylinder just below exhaust valve. I believe there is almost no air flow there. I checked with non contact thermometer and it shows all cylinders much cooler then my sensor. Maybe it's not as bad as sensor shows. I'm gonna check tomorrow with new prop which just arrived.

darod07

Short clip from yesterday.
It was hot day (31 C), my temp sensor hit 150 C with full throttle but there was no influence for engine power.

darod07

Below pictures shows final stage of my Zero assembly: drop tank and release mechanism.

Didier

Nice flight. What prop did you have in the last video? How much Flaps did you use?

Didier

Looks awesome! Is that red fillercap scale?