Cessna 170

[markm]

Hi all,

Been working on the Cessna I got after finishing the Wright Flyer. Been really enjoying the process. It is such a different model from the Wright. I've been going a bit slower this go around and trying to really understand each step and figure out how best to complete each step. The build threads here and on Virtualdome have been very helpful.

Here are progression picture from the last few days worth of work.













Thanks,

Mark

[Billy Mc]

Looks great.

[markm]

Thank you both for the kind words. I am really enjoying this build. Like I mentioned, it is much different from the Wright build so it is neat seeing how different they are but also seeing how alike they are as well.

I have finished the second wing and have decided to inlay pieces of balsa into the skeleton. It is a tedious process but one that I feel will lend to the overall look when complete. I also may send this to my uncle in Florida as he flew one back in the day so it should hold up a bit better should it travel from Oregon to Florida.

So far I have inlaid one wing. MUCH more to do!

Mark

[john8750]

Very nice work. Have fun.....

[solumn_eagle]

Awesome job! Keep the pictures coming...

[markm]

You want a few pics, here you go.

[davidchoate]

Instead of infilling wings,if I want to strengthen the wings, I will sheet the lead and trailing edges with 1/32" balsa, and then capstrip the ribs with 1/32" spruce. I did it on my Edge if you pull up my build you can see.

[David Lewis]

As a display model, balsa infill gives you a more scale-like appearance. For a flying model I don't think it would increase durability. I noticed that the wings never break in a crash. It's common, however, for the wings to pull off the side of the cabin, or the lift struts or landing gear legs to pull out.

The trick to designing a (flying) airframe is to make sure nothing is stronger than it needs to be (because excess strength imposes a weight penalty in exchange for no benefit), and to beef up the areas that always break in a crash. There are usually ways to make structural members and connections more crash resistant without adding weight.

The weak areas will reveal themselves as you gain flying experience. The overly strong areas are tougher to identify.

[markm]

Truth be told, this is for display. I don't have the knowledge, confidence, skill set to fly anything. I'm infilling more because I want it to look solid verses tissue covered. I've looked at some of David Duckett ' models and I like the way they look when painted.

Davidchoate- I'll take a look at your build.

I did just pick up the Focke Wulf 150, 500 series. Maybe I'll try to make her a flier. Thoughts?

[davidchoate]

True what David says about strength. I noticed my leading edges were always getting baged up, and on my Edge, I added ailerons, and therefore wanted less wing flex with the servos mounted. I wasnt sure what effect this would have, so I went ahead and stiffened the wing.. and the spruce capstrips were to even up the ribs between my sheeted lead & trailing edge. But anyway, also on my Edge build, I infilled alot of the fuselage for the purpose of duplicating David Ducketts techniques, and he helped, and added some comments in that thread U should find helpful.

[markm]

Can you link me to your build thread. I found one but no comments you are speaking of.

More work last night, just about finished with both wings. When you all infill, do you add some filler before you sand to get things a bit evened out or just sand until everything is smooth?

[davidchoate]

Yes. You use a lightweight spackle. I prefer Dap brand whereas Mr Duckett likes Sherwin Williams. Then you sand it all down, apply more lightweight spackle, sand, and usually # coats does it. I did a p-40 solely for display, infilled it using your exact method your doing now.Except your infilling is a bit nicer than mine. I'm not a computer genius. It took me like 6 mo. to figure out how to post a pic. but if you just keep going back, im sure you"ll find the threads. Also David Duckett (whom we all admire his work) has a thread "painting with acrylics" that is a must read. He is a very nice fellow and will usually help you all he can, but he must be busy on another project or something, cause he,s always on here. you can get lightweight spackle in small contaiers that are not that much. just be patient, and let it cure atleast 24 hrs before sanding. mine came out so smooth there was no need to cover with tissue or anything. the nice thing about display models is you dont have to worry about weight. just fill in all your gussets, and sand to a perfect shape, and finish it just as in Painting with acrylics thread, and you will be amazed. dont cut any corners as one bad area will make the whole thing look bad. I, for example, never use guillows wheels. I think they look fake.if you look arund on Hobby Zonr, or whatever you can find any size any style, and the shipping is usually more than the wheels. Oh, and dont use that wooden peg for a tailwheel please. just bend up some metal and buy a tailwheel. The super micro stuff is where you want to look. They sell me the tailwheels by a dozen in a little bag they're so cheap.Your work looks great. I can tell its gonna be a beautiful plane,just use patience. My p-40 took me a couple months, amd I feel I could've done better. Just copy Mr. Duckett. He adds extra stringers and alot of other tricks. Go through all his threads. You cant go wrong.

[davidchoate]

just go back to pages 4 and 5 youll find all those threads. Mr. Duckett relly helped me out yhere and you should read all his comments and suggestions. He is a very skilled model builder, and an all around good man.

[markm]

I've actually emailed with him a few times. Super cool guy and forthcoming with info which was awesome. I'll check out your thread as well. Just wrapping up my modeling for the night. Got the wings done as well as the tail. I doubled the balsa on the tail as I'm using 1/16 balsa. The tail parts are thicker around the border so it looked odd to just use one layer.

Anyway, here ya go.







Mark

[davidchoate]

I agree. I have used the single piece of usually thicker3/32" for tail on models, both flying and display, bit it can come out looking unnatural. especially if not covering with tissue, and if you ever look at a full scale Cessna, they are not perfectly smooth. Except for these new Raptors, and coated planes, I have been to many an airshow, and cant remember many perfectly smooth planes. Not like your car. It has to fly first, Looks are secondary, and a result of form follows function, which ,to me,and people mechanically minded, has a beauty others dont see.