Tundra RC from scratch

[speedbirdted]

This is flippin cool. The landing gear with the functional springs I especially like. You never see stuff like that on foam planes. I saw a guy who modded his to have Fowler flaps running off of two servos each, mixed on a switch so the bottom position was no flaps, middle extended only and top extended and dropped the flaps. The thing practically had to be flying backwards to stall. Perhaps you could do that and it would be easier given that you are making the wing design!

Speaking of that, how will you do the wing? Folded over design like FT does, or with ribs covered in 2mm depron I'd assume for the extra malleability? I would also think about maybe investigating nylon bolts to hold the wing on instead of rubber bands because skewers have a tendency to quickly destroy the foam around them over time, resulting in them moving around and sometimes finding their way out of the plane altogether (resulting in the wing leaving the airplane which is not preferred.) However I would then also think about using some sort of hard material like plywood or carbon fiber sheet to hold the claw nuts and associated mounting hardware that bolted mounting requires...

 

[Seahunter]

Nice work Carlos. I'm loving this design and your excellent workmanship. I will be following this build closely. Haven't started the build on my STOL simple scout yet, but have decided to build it with balsa. Plans are almost finished. Fred

 

[ssmith7113]

This is flippin cool. The landing gear with the functional springs I especially like. You never see stuff like that on foam planes. I saw a guy who modded his to have Fowler flaps running off of two servos each, mixed on a switch so the bottom position was no flaps, middle extended only and top extended and dropped the flaps. The thing practically had to be flying backwards to stall. Perhaps you could do that and it would be easier given that you are making the wing design!

Speaking of that, how will you do the wing? Folded over design like FT does, or with ribs covered in 2mm depron I'd assume for the extra malleability? I would also think about maybe investigating nylon bolts to hold the wing on instead of rubber bands because skewers have a tendency to quickly destroy the foam around them over time, resulting in them moving around and sometimes finding their way out of the plane altogether (resulting in the wing leaving the airplane which is not preferred.) However I would then also think about using some sort of hard material like plywood or carbon fiber sheet to hold the claw nuts and associated mounting hardware that bolted mounting requires...

The original Tundra uses an aluminum spar tube running all the way through the fuselage. This requires plastic holders that are glue to the wing and fuse and screwed (small machine screws) to each other. If I think about it, I may take some pics of mine disassembled. It might give some inspiration.

 

[cdfigueredo]

This is flippin cool. The landing gear with the functional springs I especially like. You never see stuff like that on foam planes.

Hey, thanks for your comment.

I saw a guy who modded his to have Fowler flaps running off of two servos each, mixed on a switch so the bottom position was no flaps, middle extended only and top extended and dropped the flaps. The thing practically had to be flying backwards to stall. Perhaps you could do that and it would be easier given that you are making the wing design!

That sound really interesting and also not to much hard to do. My problem is that my Tx does not allow mixes, al also my chanel 5 is only two positions.... So... no way. I will put some photos soon of the flaps mechanism i am working on. Pretty close to the original Tundra.

Speaking of that, how will you do the wing? Folded over design like FT does, or with ribs covered in 2mm depron I'd assume for the extra malleability? I would also think about maybe investigating nylon bolts to hold the wing on instead of rubber bands because skewers have a tendency to quickly destroy the foam around them over time, resulting in them moving around and sometimes finding their way out of the plane altogether (resulting in the wing leaving the airplane which is not preferred.) However I would then also think about using some sort of hard material like plywood or carbon fiber sheet to hold the claw nuts and associated mounting hardware that bolted mounting requires...

You are pretty right, i am going for a folded over design using ribs and 2mm depron. This way will be asy to place all the mechanisms, because i would like to use only two servos, one for flaps and other for aileons. And also i want to add ligths to the wings. This technique was the same i used on my biloute and was pretty strong and lightweigh.
And yes, i am planing to make the wing removable, but using regular bolts and screws, because icant find that kind of plastic hardware here where i live.

 

[cdfigueredo]

Nice work Carlos. I'm loving this design and your excellent workmanship. I will be following this build closely. Haven't started the build on my STOL simple scout yet, but have decided to build it with balsa. Plans are almost finished. Fred

Thanks Fred!!!! I will be trying to post updates daily. By the way, i love balsa planes!!!!!

 

[cdfigueredo]

The original Tundra uses an aluminum spar tube running all the way through the fuselage. This requires plastic holders that are glue to the wing and fuse and screwed (small machine screws) to each other. If I think about it, I may take some pics of mine disassembled. It might give some inspiration.

Thanks fot the data. I am thinking to build the wing in a single piece, so it won;t be able to deattach it form the center part. I think i will use wood sparst to reinforce it.
I will really apreciate some photos of your. Thanks in advance

 

[cdfigueredo]

I've been working on the flap mechanism and this is what it looks like.


The hinges are simple plastic pieces form an old CD's box and a servo screw. For action it i use a servo arm section and a guitar string as pushrod, it is flexible but strong enough.


I need to refine it, but i think it will work well, and also looks like Tundra flaps. What do u think?

 

[cdfigueredo]

Lets go with the lights!!!! Check this Ultra Bright impermeable LED Bike Light Set from amazon. I got two as a gift from a friend and they're amazing. It has 3 modes, solid light, slow blinking and fast blinking and alternating between the two LEDs. My original plan was to use the alternating blink mode and use one white LED on each wing as the strobe lights. Good, right? But I burned it out with a very powerful soldering iron... so I screw it . But still, it's an excellent plan to try.

So, right now I just have solid lights. Since I only had white LEDs, I painted them with red and green markers. They don't lose any brightness and the color is really realistic. Plus, they're permanent markers.


And this is how they look inside of the fuselaje. The 2mm depron works as an excellent light diffuser.


As my Tx only have 5 chanels i will conect flaps and lights using a Y-harness. The diagram bellow shows the connection of the LEDs direclty to chanel 5.

 

[Seahunter]

I've been working on the flap mechanism and this is what it looks like.
View attachment 157702 View attachment 157703

The hinges are simple plastic pieces form an old CD's box and a servo screw. For action it i use a servo arm section and a guitar string as pushrod, it is flexible but strong enough.
View attachment 157704 View attachment 157705 View attachment 157706 View attachment 157707 View attachment 157708

I need to refine it, but i think it will work well, and also looks like Tundra flaps. What do u think?

Looks good but before you settle on this check out the FT article May 6th, 2016 by Andres/Josh " How to make fowler flaps, P38 Lightning"
Complicated but worked well. I am amazed by the performance of that P-38 indoors

,

 

[cdfigueredo]

Looks good but before you settle on this check out the FT article May 6th, 2016 by Andres/Josh " How to make fowler flaps, P38 Lightning"
Complicated but worked well. I am amazed by the performance of that P-38 indoors

,

Wow Fred that is really interesting. Those flaps make this plane really slow.
But i think it is a very complicated mechanism for my right now. I think i will go for the simple way.

 

[cdfigueredo]

It is a fact now. Tail is finished, just left to attach the rudder, but must wait till joint the tail to the fuselaje.


Some details of the rudder and fin

 

[cdfigueredo]

I covered the center fuselaje section, but i forget to add the wing struts suport . Let's see how i will solve it without remove this part. I am very happy with the result... looks good and also really strong and lightweigh.


Everithing is 226g... no bad

 

[cdfigueredo]

Was working a bit yesterday on the nose, i made it detachable. It's held with two barbecue sticks and maybe some magnets.

 

[cdfigueredo]

Hello everybody!
I made some progress this weekend, not as much as i wanted but it is a lot of new things. Tundra now is maybe 70% done.


I started with the wings too. I am adding some LEDs... it is not too much but i think it will work, not super bright but will work.


The center piece will hold the two servos, one for ailerons and the other for flaps.


The whole wing

 

[CrazyFastFlying]

Hello everybody!
I made some progress this weekend, not as much as i wanted but it is a lot of new things. Tundra now is maybe 70% done.
View attachment 158239 View attachment 158240 View attachment 158241

I started with the wings too. I am adding some LEDs... it is not too much but i think it will work, not super bright but will work.
View attachment 158242 View attachment 158243 View attachment 158244 View attachment 158245 View attachment 158246 View attachment 158247 View attachment 158248

The center piece will hold the two servos, one for ailerons and the other for flaps.
View attachment 158249 View attachment 158250 View attachment 158251

The whole wing
View attachment 158252

View attachment 158253 View attachment 158254 View attachment 158255

And the whole thing is made from foam board???!!! WOW!

 

[cdfigueredo]

And the whole thing is made from foam board???!!! WOW!

Well, it is not foamboard, it is depron, but i am pretty sure that foamboard would work as well.

 

[CrazyFastFlying]

Well, it is not foamboard, it is depron, but i am pretty sure that foamboard would work as well.

Ok.

How thick is the depron?

 

[cdfigueredo]

Ok.

How thick is the depron?

It is 5mm when you take the skin off.

 

[CrazyFastFlying]

It is 5mm when you take the skin off.

Ok, that's the same as foam board!

What's the the difference between depron and foam board?

 

[cdfigueredo]

Ok, that's the same as foam board!

What's the the difference between depron and foam board?

Yes, it is the same..
The main difference is that depron is rigid, so if you try to bend a 5mm thick piece of depron you will break it. So you have to bend it using techniques like those in the master series, and it's also convenient to apply some heat. Whenever I need to fold it, I use 2mm thick sheets that are easier to fold using the edge of the table as an auxiliary.
One advantage is that you can sand it for an excellent finish, but I guess you can do the same with foamboard. I personally use depron because I can't get foamboard where I live.

Take a look to this https://forum.flitetest.com/index.php?threads/building-with-depron.5900/