Cessna 182 Balsa Build

[Joker 53150]

Until I get mine airborn to know for sure, I think adding flaps and floats would add way too much weight to an already heavy plane. I'm not saying it can't be done, but if I were going to try it I'd probably put the basic airframe on a major diet first.

 

[dja2424]

What would you suggest eliminating for this diet? I'm not sure all the sheeting is necessary . . . I saw the stick built tail parts which could help. Other ideas? Thanks.

 

[Joker 53150]

The tail is especially heavy. Not only the horizontal/vertical surfaces, but the structure inside the tail as well could be lighter. The balsa sent with my kit was very heavy and could be swapped with lighter stuff. The wing is over-built in my view, and could have been designed lighter.

But keep in mind that mine hasn't flown yet so I can't do more than compare against other kits I've built which have had lighter wing loading. Maybe this will fly very nicely, although I expect it will require me to keep the speed up.

 

[dja2424]

Yeah I was thinking the flaps would be a good idea to slow the landing speeds down, knowing that floats would make it heavier right off the bat. I don't really have a frame of reference for what is heavy wood vs. light. Most of the balsa in my kit seems very lightweight/fragile, while the plywood seems pretty dense/sturdy.

I haven't got to the wing yet, but that will probably determine how to proceed. Not sure I can even get servos in the space provided by the wing depth, so that may be the determining factor for that.

Has anyone out there actually finished and flown this plane? It would be great to hear some flight reports! Anyway, gonna plug along and see how it goes. Thanks for the feedback. Any other is welcome.

dja2424

 

[Joker 53150]

I haven't heard of anybody actually flying one yet, but really hope to get confirmation on the CoG before mine is ready. Either way, mine WILL fly, purely out of spite for the crappy instructions. Either it'll fly through the air or fly into the ground at a high rate of speed.

 

[dja2424]

That's one way to make "balsa dust." Hopefully it flies well!

dja2424

 

[artw]

Joker, did you use the stock motor mount?
I did and I find the turnigy D2826-10 1400kv sticks out a bit too far for my liking.
I was planning on creating a "shim" on the cowl/fuselage interface from leftover 3/16" balsa I had from the tail sticks
the cowl is already far too forward and this would push it out this much further BUT at least the prop won't be 1/2" away from the face of the nose.
Art

 

[Joker 53150]

The motor mount isn't installed yet, and I'm pretty sure the stock version won't work for me. Once I finalize my choice in motor I'll build the mount to get the prop and spinner in the ideal spot.

 

[artw]

This is what I ended up doing. I will be able to sand the shim as required to get the nosecone to be "centered" on the axis of the motor. I can cut about 1/8" off the shaft so the collet sits closer.
anyone else who hasn't got this far yet - dryfit the cowl parts on the fuselage before gluing it. I did it by eye and it doesn't quite line up.
there is a photo of it without the shim added in my taildragger thread.

 

[Joker 53150]

My build is getting close enough to completion that I can get a reasonably good idea as to the final weight. Depending on what motor/prop/spinner combination I use I'll end up around 525-550 grams not including the battery (assuming I don't have to add lead to get the CoG correct). Something about that weight was bugging me, so I looked back at one of my old posts:

Interesting... I just noticed the last line of text on the "instructions" says the take-off weight is 220 grams, and empty weight is 200 grams. Anybody got a 20 gram 1300-2200mAh battery? And I'll be surprised if I can fit more than a 1500 in the battery box, much less a 2200.

Realistically, their claim of 220 grams is probably just a mistake. Or a complete lie. Possibly just a random number pulled from somebody's ass.

Then I went to Hobby King's website to look at motors and checked the stats on the 182, and noticed they list the bare airframe weight at 500-550g without covering and the AUW at 750-800g. Were those wights there previously? I don't remember seeing them before. If their bare airframe doesn't include covering, I would assume it also doesn't include electronics, so at that point 500-550g would be correct if you used the heaviest balsa on the planet! My build should end up close to the 750-800g range they list depending on my battery weight. I'm still thinking about using a 1500, but we'll see how it balances first.

I compared the current weight of the plane against another balsa build I did, the Navion I built for the Model Airplane News "Build to Win" contest. The Navion was a pig at around 675g without battery, thanks to the retractable gear and heavy construction methods I used, but it flies nicely and cuts through the air well. The weight forces me to keep the speed up, which is fine until it's time to land. For the size of the plane it's still on the heavier side compared to others I've built. The wing isn't very large so this should translate to higher wing loading. Eventually I may do some math to figure out the actual numbers.

Also, the covering is almost done, as shown in the pictures below. A few little spots to tidy up, windows need to go in, steering linkage and pushrods need to be attached, etc. The "little" stuff that takes forever!

But at the end of the day, I'm honestly just not thrilled with the design/look of this model so I haven't spent a lot of time getting creative with the fuselage covering design. I'm still going to cut some vinyl numbers for the sides, but other than that it's going to be somewhat plain. The biggest thing I dislike about the plane now is the cowl. It's just a big blocky blob of lazy garbage design that ruins the rest of the plane. Like putting Mike Tyson's face tattoo on a super model's face with a Sharpie marker. After the plane flies (fingers are crossed) I might consider building a better cowl from scratch. We'll see what happens in Spring.

 

[dja2424]

Nice job!

Looking good! I hope mine looks 1/2 as good when it's done. Good luck getting it in the air!

dja2424

 

[artw]

I decided to cut the motor mount instead of using the shim.

 

[Joker 53150]

I like it, a simple solution!

 

[artw]

Did anyone else notice that in the wing assembly photos the spars appear to be laser cut ply, and in our kits they are balsa?
do you think it would be prudent to install some shear web blocks at least along the main spar?
joker have you given your wing any sort of load testing yet? like pick it up by the wing tips and bounce it around?

 

[Joker 53150]

I didn't see anything of real concern on mine. Since it's got two spars, plus the leading and trailing edge and the LE sheeting I think it has enough structure to be safe.

Or I might be completely wrong...!

 

[artw]

sounds good it probably doesn't need any extra weight anyway.
I am about to give the wings a go.

 

[artw]

I have laminated wing rib W1 and W2 together and am at the point where you glue it to the ends of the spars.
I assume at this point is also when you set the dihedral. There is a fair amount of slop here so the dihedral can be anything you want really. looking at the full scale pictures it looks to be about a degree or 2 it is not very much.
My plan was to cut a piece of wood with the required angle and use that as a "square" so at least both wings will end up with the same amount.
what did you guys do here?

 

[Joker 53150]

I didn't pay much attention to the dihedral, and just assembled the wing. It's got a tiny amount of dihedral, but minimal at best. Hopefully the ailerons do their job well!

 

[colorex]

I learned a lot from reading this thread. "Don't buy chinese kits"?

seriously though lots of good info.

 

[Joker 53150]

"...unless you like a challenge"

They can be a great value, but are not for everybody.