Mini Me163b Komet build

[Jade_Monkey07]

Time for a build page! Copied the initial text from the scratch building thread
-Started my Mini Me 163 Komet build the other day. This is one I've wanted to build for a while. I saw some other komet builds on here but I am a fan of scale looks so that pudgy round shape feels essential to me. At around 500mm i Started with the wing and profile view, to be fully 3d skinned in 1mm depron after.
Wing consists of 2 layers of dollar store foam. Bottom layer keeps the paper and gets a half of a giant bbq skewer in the center as a strut and the leading edge gets the other half which is used to start the aerofoil profile. The top sheet then gets paper removed and sanded to a very sleek profile. She is going to be built for speed in mind.
So far she sits at 60 grams with the motors(yes 2) 1202.5 11500kv 2s
for now it glides very well and the wing is so strong it could take off someone's head. I am aiming for 110 grams fully loaded 2x 450 mah 2s batteries, one for each esc and a 100mah for reciever(I like redundancy in case the motors quit) and also should be able to fly with just one motor no problem if I want a more tame flight experience. The maiden will likely happen with just the pusher. it should have around 250 grams of thrust in this tractor and pusher config
Ive got the fs2a reciever ready and the Escs just showed up in the mail so I can get all the wiring done soon. I'll be short on 1.7g servos for the build so hopefully I total one of my other builds as a ritual sacrifice to Ze Komet gotts.

 

[Jade_Monkey07]

Of course my flight weight increased to 145 grams because I cant math apparently haha.
Did the maiden flights today and first few didnt go well. The elevons being the entire wing makes it extremely sensitive in the roll axis even on the lowest throws and 50% rates. Expo at 50 also. Smashed the nose in a few times before I got the cg perfect. But now shes trimmed flying acceptably. I will replace the broken nose and start skinning in the next few days. I was really hoping to keep the weight down so i might ditch the rudder servo and see where else she can lose some weight. 50 grams in batteries doesnt help the situation. I could also solder all the wires directly to the rx. That might be over kill though. Doubt I can shave more than a few grams unless I switched it up to only one motor. then I could lose 35 maybe 45g with some other changes.
Might build a second one with just a single motor and lighter construction to see which is faster.
These high kv motors are quite rapid but dont have the torque to pull much weight compared to some others. My bang good 48cm glider conversion seems faster than this with only one motor at 85 grams.

 

[Jade_Monkey07]

If anyone is familiar with calculating speed from sound bytes I'd love to see how fast this and the bang good glider are. I got some proper sound files of the glider a week or so ago. Just havnt sat down to learn how to calculate it.

 

[GrizWiz]

If anyone is familiar with calculating speed from sound bytes I'd love to see how fast this and the bang good glider are. I got some proper sound files of the glider a week or so ago. Just havnt sat down to learn how to calculate it.

Looks fun! I am working a Ho-229 for the EZ Pack

 

[Jade_Monkey07]

Looks fun! I am working a Ho-229 for the EZ Pack

Always loved those. I worked at the aviation museum in Ottawa when I was younger and they have a complete komet that always fascinated me with having no "tail" I made a horton glider when I first got back into building rc stuff. Super simple and lightweight with the powerup module.

 

[GrizWiz]

Always loved those. I worked at the aviation museum in Ottawa when I was younger and they have a complete komet that always fascinated me with having no "tail" I made a horton glider when I first got back into building rc stuff. Super simple and lightweight with the powerup module.

Cool! I was thinking I was going to need a vertical stabilizer but it flies straighter than a dart

 

[Jade_Monkey07]

Not the maiden crashes. But the first flight that went properly.
"Maiden" video

 

[JustPlaneChris]

If anyone is familiar with calculating speed from sound bytes I'd love to see how fast this and the bang good glider are. I got some proper sound files of the glider a week or so ago. Just havnt sat down to learn how to calculate it.

This video has a link to software that lets you measure sound from a WAV file using doppler analysis. It's pretty darn accurate too! I found some videos where they were using radar or GPS to measure speed and captured the audio to run through that software. It was usually within a couple of kph of matching.

Oh, and cool project too!

Chris

 

[Jade_Monkey07]

This video has a link to software that lets you measure sound from a WAV file using doppler analysis. It's pretty darn accurate too! I found some videos where they were using radar or GPS to measure speed and captured the audio to run through that software. It was usually within a couple of kph of matching.

Oh, and cool project too!

Chris

Awesome thank you!

 

[GrizWiz]

Pretty darn fast!

 

[Jade_Monkey07]

wow that software was pretty easy to use!
my 2s 1202.5 powered 48cm bang good glider came up with 91kph(56mph) and 103 kph(64mph) on 2 runs with and against the wind. super happy with that! ill see if the komets video is good enough. I dont think i was close enough to the camera to get an accurate reading

 

[Jade_Monkey07]

the sound files from the komet video are hard to read. im getting anywhere from 120 to 140 kph. but im not going to count that. ill do a proper setup in a few days and fly directly over the camera and see what i get

 

[Jade_Monkey07]

Tore off the top and bottom and restarted with 3x foam keel since it's the landing gear. Removed the paper for weight.ill be cutting a slot in this to house the batteries once the turtle decks are mostly made.

Next I printed out the formers and I'll be using these hefty brand styro plates to make the turtle deck. The plates are about 1.5mm thick and coated with cellophane on both sides. The cellophane peels off nicely just like the paper on the regular foam board. With the cellophane the weight is similar to foam with no paper. It has a grain so it strong in one direction and rolls nicely in the other. I'd say it's similar strength to the foam board without paper. When the cellophane is remove it's a bit less than half the original weight. So it's perfect to skin with except that its pink. I'll be leaving the outer layer on to add a bit of strength but also red is the color I'm going for. This stuff is also slippery, so maybe it will help reduce surface drag? One can hope anyway.

Formers done.

For the skin I will strategically be cutting the rounded edges of the plate to suit the curves I need. It's pretty versatile stuff.

 

[Jade_Monkey07]

I Managed to get some work done on the Komet.

Remounted the front motor. And started the skinning. Lots of trial and error at this point but I think the shape is coming together pretty well.

I'll be making a hatch out of the whole spine piece so its not glued down yet. Top should be finished this evening hopefully.

I will also be re-using the peeled off cellophane to cover the white foam.

Some big changes to the wing tips are coming. I was dealing with some tip stalling in the maiden and Since it was so twitchy in the roll axis I'm going to make new tips, shortening the elevons and adding some washout to help with the tip stalls.
"Alright, Back to work!"

 

[Jade_Monkey07]

Got a bit more done. Battery slots for the 5 batteries made up.

100mah rx battery

Motor/ esc batteries in series 2x 450mah on both sides.

Panels glued up. Just need to make a hatch for rx battery.

 

[GrizWiz]

Nice!

Got a bit more done. Battery slots for the 5 batteries made up. View attachment 203531
100mah rx battery View attachment 203532
Motor/ esc batteries in series 2x 450mah on both sides.
View attachment 203533
Panels glued up. Just need to make a hatch for rx battery.
View attachment 203534

 

[Jade_Monkey07]

Canopy magnets mounted. Tail covered, elevons shortened and wingtips replaced adding 5 or so deg of washout.

Far from good. But looks good from far. Wont be able to tell how rough the skin looks as it flies past at 120 kph

 

[JetCrafts]

wow

 

[Jade_Monkey07]

Almost there! Just lower battery hatches and wing covering and shes ready for the air again

 

[Jade_Monkey07]

The body is finally done, so Remaiden day! I havnt decided exactly what to do with the wings yet color wise. Might do tops red and bottoms mostly white.

First flight youll see right at the end the escs both got so hot they desoldered themselves. After fixing them for flight 2 I opened up some vents over the esc. I got a few more flights in, with a silly crash that was my fault. I then went to do some speed runs to doppler the speed and managed to overheat the boards again and they desoldered a second time. I've now widened the scoop and the exhaust. I only managed to get around 95 kph before they konked out that time. I was hoping to break 100. I'll try again next time I get to fly.
But for now here's the remaiden video with a crash!

Might still be uploading if you're too quick!