FTFC´18 WWII Lippisch P13a designed by Dr. Looping Looie

foamtest

Toothpick glider kid
It all depends on what battery you can fit inside of there and how heavy you want to make it. If you are looking to make it as light as possible go with the cheap hobbyking one so you can use a smaller battery and still get decent flight times. If you want speed and can fit a larger battery then go for the FMS one. Also take into account if the model would be too under powered with the Hobbyking set up when fully loaded up, if this doesn't apply then just ignore this. Take this all with a grain of salt though because I've never messed around with EDF's before so I'm just using my general knowledge of prop planes to make this assumption.
 

Dr. Looping Looie

Elite member
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Thats the progress. Actually recocnizeble. Just found out how I can upload pictures from my phone, which meens you will see more. Prozess of making the control surfaces will include some nice tecniques, so be prepaired for this. 3s 2200 fits perfecly in there, and the extra weight of the heavier setup is less then the extra thrust, but I worry with the short wings, on the other hand, the wings are really thick, so I think I will pick up this one that is less expensive.
 

Dr. Looping Looie

Elite member
Ok, now we are going to build the control surfaces.
It will include very advanced techniques that are made to reduce drag and keep the shape as scale as possible. Its not FT-style, but yesterday I found the nerdnic speedwing and this has the same Idea. You can go with more FT-style rudder and elevons, but this would leave a thick trailing edge and could cause problems with the shape. Sadly, this build does not feature so many FT build tecniqes, because round shapes are so important in this model.
But now lets begin:
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First we need the control surface parts. They have reference lines which should not be cutted, so watch out with laser cutters!(If I am able to create laser cutter compatible plans)
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We peel of the paper a little further than the refference line. Make sure you can see the reference line on the foam core!
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Cut it along the reference line!
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Open it up!
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Remove the foam core! Also, pull the paper a little more back.
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Cut a kind of double bevel so that the tip is at the reference line and at half the thickness of the foam core. Check the picture for reference!
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Now glue it just as shown in the picture! Make sure to pu as less glue as possible in the area f the tip, because this is the area the rudder is moving. Also make sure you spred the glue over the whole surface, because otherwise you might have thick glue mountains in your hinge.
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Now remove the paper ftom the control surface side!
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Bevel and sand it down on both sides like this to create a nice aerodynamic shape. Then glue the paper back to the foam and finish the trailing edge!

I hope you could follow. If you have questions, ask me!
Next thing will be joyning the control surfaces to the wings!
Dont forget to repeat the same process with all three control surfces! Use little glue to make the surfaces move! Also contiue with the sharp trailing edge over the wingtips on the elevons!
 
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Dr. Looping Looie

Elite member
Ok, now I want to show you how to install your control surfaces to the rest of the plane!

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First we pull off the paper on one side. I m using the top fin piece and the rudder. This piece looks like a F-117 nighthawk, right?
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We bend it to create a nice shape
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Now comes the special part: bevel and sand the trailing edge down so that there is half of the foam removed where the control surface are attached to it, so the control surface and wing are nice and flush. We also remove foam from the top or wingtip to allow it to become a sharp edge. And sand the foam down to zero at the back of the trailing edge, so that everything is smooth. You may have to work a little, but make sure it looks the same on both sides.
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On the wings, remove extra foam for the nozzle. But we will talk about that later.
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Now we glue the control surface to the wing on one side. Tip:
Sand the brown paper before you glue it, because it will stick way better.
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Apply glue to the trailing edge and other side of control surface hatch and close it to get the nice shape. Always check for good movement of the control surfaces.
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Now take the rocket nozzle and cut a hole in the back of the fin. I want the nozzle to stick out a little, so i made my hole not that big.
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Now glue the nozzle to the back and it looks amazing! You could probobly add a little rocket to the back to arcive insane speeds!

So, thats it. I hope the new way of installing control surfaces works nice. Next will be about making the construction stronger and putting the wing halves together.
 

foamtest

Toothpick glider kid
Wow, this thing is amazing! I can't believe the amount of detail you can get out of foam board. Well done!
 

Dr. Looping Looie

Elite member
The following funktion is optional and needs LEGO technic suspension and 1.5mm plywood
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I cut out a few parts like ft mini firewall, mini control horns and pieces with a hole as big as the hole in the springs and connected them using a LEGO part
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Here they are in detail
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I also made a landing skid and formed a curve using water and sandpaper
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Then I removed a section as big as the landing skid from the bigger part
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The wooden piece fits perfectly in there
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Now I applyed the springs to the skid using hot glue. Make sure you apply the hot glue on the outer edge od the smaller piece, si that the springs can move
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This is where it should go later
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The skid should be operatrd by a servo that is connected to the spring. Thats difficult to explane, i will show you a picture soon . The skid shoul extend forword so that the shocks absorbe both the energy from moving forword and going down.
 

rockyboy

Skill Collector
Mentor
Love the sprung skid idea! Any idea what the sweet spot will be for weight with those lego parts? I could see them being useful for other scratch build designs too.
 

Dr. Looping Looie

Elite member
LEGO parts are very useful, especially technic part, when you want to build crazy functions, but have no 3D printer. One piece alone does not weight much, just a few gramms plus. with the mighty mini setup, I think my plane weights 300-400 gramms, with the EDF a little heavier, but not much. The LEGO pieces will be very heavy in big structures, I have the lego technic Porsche 911 GT3 RS which weights around 2.5 kilo gramms, but with 2704 pieces, its super massive. The biggest problem with LEGO is the power, because they are using their own connectors, so if you want to operate pneumatics, which work with compressed air, to recreate hydraulics for super nice and realistic retracts, you have to modify the parts heavily or use the extremely heavy LEGO electronics, which are heavy, slow, weakand inefficient.

Springs are one of the parts you are most likely using in a light plane, but for a nice heavy bomber, the extra weight for pneumatics is the coolnes worth.
 

Dr. Looping Looie

Elite member
Ok one week left but its possibly doable

First of all I want to wish you a merry cristmas and happy flying in 2018!
Now I have holidays which means tons of time, and there is not much to do, just electronics and details.
The main next step is the hatch, which is probably the most difficult thing on the whole model.
I got the FT F-pack to cristmas and also the FMS EDF, I just did a thrust tes at half throttle and it sounds amasing! Theres nothing to hear from the motor, but the air produces a very loud noise, which sounds cool, but I dont know if superloud air is a good thing.
Alright, here are coming more pics:
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I joined the two lower winghalfs, attached ailerons just like the rudder and glued in the nozzle. For those who dont know, the nozzle is flat like a fishtail exhaust in this plane. I also did the trick with peeling paper off, removing foam and glueing paper back on to get the hole bigger.
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I made servo holes in the upper surface.
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I made spars to straight the wings up and to hold the servos. The ends are heavily beveled because the wingtips are very thin.
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I glued them in at differebt areas to leave more room in the tail so that the airflow is better.
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Heres a picture of the EDF
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It looks very finished, but its not glued yet because I have to fit the EDF in there and make a hatch, so I placed weights on the wings to hold them down.

Overall I think I can make it in time, but I dont know how to create plans. Do you know a good article or forum threat that shows me how to do it?

Have a great cristmas!
 

Dr. Looping Looie

Elite member
I just build retracts out of lego. Iwant to include similar working ones in a Heinkel He 111 if I build one. They have a airtank to store compressed air, so that I can use them a few times. These are cool details you can add to your plane if you dont have a 3d printer.
 

Dr. Looping Looie

Elite member
The cockpit
The whole cockpit is build entirely using foam board, hot glue, skewers and paint!
This is optional, but I think I build one of the best cockpits in a foamboard airplane.
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First I put the instrument panel and back piece in the coockpit. These parts also help with stability.
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Next is a part with rudder padels and a single bevel
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Next part is the seat. It just looks great, but its foamboard and the nice shape ws created using soldering iron to melt the foam. Then I painzed it black and drew lines with a pencil to recreate the lines on a seat. I also made a bottom plate. I painted everything in black using a marker. It drys fast and sticks nicely to the foam.
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Here is everything together. I added instruments, a joke made out of a skewer with foam boards paper around the top and a drop of glue as a firebutton. I made bevel cuts into the skewer to bend it and get the nice angles. I also windet a piece of paper around the bottom for the base. I added a panel with thrust lever, a switch and a button next to the seat. The switches are made out of toothpics painted with a pencil. On the instrument panel are also two drops of glue painted red using a marker. This makes nice buttons or lights. There is also a target cross (Fadenkreutz) in the front made out of wire.
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I also made a canopy out of windowcolor foil. This is foil that is thick enouth to stay in place nicely. The cool thing is that the canopy is removeble because I added a rim of glue around the edge and it does a nice friction fit.
 
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Dr. Looping Looie

Elite member
Almost done!
The only thing I have to do is installing the electronics.
Electronics weight is around 300 gramms, dry weight without electronics is under 200 gramms. That means under 500 gramms, at 650 gramms of thrust, we have over 150 extra gramms to go vertical!
I hope on the evening are all systems running so that i can take flight in the morning when the wind is not that bad.
 

foamtest

Toothpick glider kid
Hey I believe this could help you a lot, its called a hot knife.
hotknife.PNG
I got mine from a local craft store but you can find them online, like this on here
https://www.wirecare.com/interest/i...mpT4T4psVGfa-UO4VyCFnWY7R-IDP7AoaAm1aEALw_wcB
I don't know if it'll ship to Germany but I'm sure you could find one. It's awesome for cutting foam board and cutting curves, intricate details, melting foam away to add nose weight to chuck gliders, etc... It's great and I think everyone who makes anything out of foam should have one.
 

rockyboy

Skill Collector
Mentor
This is awesome! I'm really excited to see it fly - just looks so weirdly proportioned it should be a great attention getter at the field! :)