vuoladodo

Hello everybody.
I do a lot of depron building and for quite a while I have been eyeing the Polikarpov i 16 (Rata).

Finally I decided I will go ahead and start the process. Anyone is welcome to join and document their build as a build-off. The link to the plane is this:


I took the file from a Polish guy who puts them online and enlarged it to get a 1.05m wingspan. These are the PDF's with for paper:

[ATTACH]1941720[/IMG]
[ATTACH]1941721[/IMG]
[ATTACH]1941722[/IMG]
[ATTACH]1941723[/IMG]
[ATTACH]1941724[/IMG]

The first step will be to cut the firewall (4mm plywood) and the formers of the fuselage (2mm Balsa).


I took a cheap compass plased the sharp tip at the center and the lead on the permitrical line of former A (PDF 1) and marked the circle on the plywood. Next I will cut with a hand copping saw. Not today though.
Here are the pictures:

vuoladodo

Chapter 2: Cutting the Formers.

So, I finally managed to get back to the Polikarpov. I took the plywood with the firewall marked on it and using a coping saw, I cut it and did some light sanding.


I took two pieces of 100 cm x 2mm x 10cm balsa wood and glued them together along the long edge with crazy glue getting a 100cm x 2mm x 20cm board.


This can accomodate now all the formers. So I cut formers B, C, D, E and F from the paper plan.



Then I taped it to the balsa and marked each with a sharp B pencil. Then I cut each piece of balsa ending with 5 balsa formers (+ the plywood firewall).



The paper plan calls for two formers per letter. I think I will add to each former a depron doubler. though I am not yet sure. Much depends on how i decide to resolve the skin in this project. As you can see in the plan, the skin is sectioned and attaches to each former. I am not sure how I will modify this, if anyone has any suggestions, I would love to hear them.

OK that's all for now.
VD

vuoladodo

And one more. I taped together the print-out with the skin sections and cut them out.

Then marked the center of the former's circle. Some of them are themselves circles like B and F and some others D and E, especially, have circles marked on them to show the point of alignment with other formers.

I then used the center point to mark a 2cm x 1cm rectangle and cut through it. Marked the end of each skin on a 2cmx1cm balsa and put the formers through. This is the placement of the fuse core.



VD

vuoladodo

ANyone out there?

fredo

Nice project I don't know how accurate are those paper templates but it all depends how far you want to go. First of all, by now you should have a pretty good idea how heavy it's going to be and what motor you want to use. Keep doing it and don't get discouraged. The end result can be very rewarding.
I build my rata about 10 years ago. There were absolutely no plans, so I found a 3 view drawing on some russian web site. Ended up making my own plans. It was a great flyier. Powered by OS120 four stroke. and 70 inch wingspan.
Made my own retracts as well. Yes, it was a lot of headache at times but the plane itself used to turn heads on every occassion. Here are couple of pics. One in flight and landing. I hope it will go as well for you as it did for me. Btw, the plane is made by Mr. Polikarpov. [ATTACH]1944092[/IMG]

vuoladodo

Hi, given the rather meagre response I am moving the thread to Watt Flyers, if you are interested you can follow the rest here:
http://www.wattflyer.com/forums/showthread.php?t=72695