L-19 Bird Dog, Balsa Scratch Build

[Joker 53150]

After a half-dozen flights I can finally say that the wing warp issue has been cured and the plane flies very nicely. Shimming the trailing edge of the wing up on the "low" side did the trick. Now that I know it's good I can finish a few details to make the shim permanent. Today I ran a couple batteries through it and the performance is what I'd consider scale for this type of plane. Limited vertical pull, but it cruises nicely at 1/2 throttle thanks to the wing design and the copious amount of lift it has. Even with the extra nose weight I had to add it floats in nicely at landing speed.

The plane wasn't difficult to build and I think it's pretty much exactly as advertised. It's a simple park-flier that forces you to relax. It isn't fast, it isn't aerobatic, it isn't flashy. It's fun on a calm day when you want to just burn some batteries and enjoy some sedate flight time.

 

[Foam Addict]

:applause:
Very nice! Great build, I'm glad it flies so well.

 

[Joker 53150]

A quick follow-up on the L-19... When I got the plans for mine I purchased the short-kit for my dad, as he always liked this bird. It's taken the back seat a few times, but is finally getting close to completion! He sent me pictures of the bare balsa, being prepped for paint. The cabin is all sealed up and the first coat or two of sealer is on. As he's more patient than me, the quality of his work is much better than mine.

His short-kit had the same exact problems my plan-built kit had, with inaccurately cut parts. The quality of the cutting was fine, but whoever did the cutting evidently never tried assembling a plane from the parts. It's too bad, as otherwise it'd be a great value for a short kit. Hopefully their other kits/plans aren't screwy like this as I've got plans for other planes of theirs.

 

[SnowRocker88]

Looking great!

 

[Joker 53150]

Here's my dad's latest progress pictures. Next update I see will probably be with it sitting next to mine, finished and ready for a maiden.

 

[Joker 53150]

Today has been a good maintenance day in the shop. The L-19 gets some work, my Navion contest plane's landing gear gets adjusted, the Ki-61's gear is fixed, the Super Cub's float wires are repaired, construction continues on the 1/4 scale Pietenpol, and if time permits I'll also tweak the wing saddle on one of my Red Swan gliders.

The L-19 has been collecting dust for a while and I wanted not only to get it out to fly again, but also clean up the half-assed "fix" for the warped wing. The wing itself has some warp to it that I haven't been able to remove by steaming, cutting ribs & re-gluing, etc but I noticed a while back that by lifting the right trailing edge at the fuselage it forced the wing into a more "level" attitude with respect to the fuselage. A couple scrap pieces of balsa were wedged in and the plane flown like that. But it's time to fix it.

This is what I'm shooting for, an even wing. 3/16" of lift at the right side T.E. does the trick.




In all it's less-than-glory. It's ugly, but it works.




Balsa sticks were cut as needed to give me a flat wing saddle. Once glue is dry I'll do a little filling, sealing, and painting. For the most part, this fix shouldn't be very noticeable unless you know what you're looking for. If we can ever get a nice calm day without wind around here the L-19 can come back out to the field with me (it really hates wind....).

 

[SnowRocker88]

Haha, clever fix!!

 

[DarkFire]

Don't know if anyone will see this considering the last post was 6 months ago, but hey.
Awesome work on a cool plane!

A whole bunch of questions:
What power setup was used?
Do you think a power system from a UMX plane will work?
Do you think this would be a good first balsa build for a pretty confident guy with plenty of foamboard skills?
From looking at pics i can pretty confidently guess this is three channel. Is that right?
And finally, how does it handle wind?

Thanks,
Dark

 

[Joker 53150]

I keep an eye on most threads in the balsa area, so no problem finding your questions!

For answers:
- I don't remember exactly which motor I used, but it's a little smaller than the Park 450 size, running a 3S 1,000mAh pack.
- The UMX power system would NOT be a good choice, it's way underpowered for this plane.
- It's not a difficult balsa plane to build, except for the mistakes on the plans. Although I'm not sure if you can get just the plans for this plane without buying the kit from Rich Uravitch.
- Correct, it's 3 channel.
- It's not a big fan of wind, being somewhat light and only 3 channel. It's fun to fly on a very calm day, and as expected it is not aerobatic, it's simply a relaxing flyer.

With all that said, if you haven't built from balsa before I would really recommend starting with a GOOD kit. Not a cheap one from Hobby King, or a "builder's kit" from companies like Sig. I've made the recommendation a lot before, but starting with a fairly simple GOOD kit like the Lucky ACE from Mountain Models (if you're a confident pilot) or the Mountain Models Switchback (if you want an easier flying plane) will help ensure that you actually finish the plane. Scratch building from a plan page isn't necessarily hard, but it does increase the difficulty, slows down the build, and relies on the builder to make straight & clean cuts to get a nicely finished plane. The kit will certainly cost more, probably 2 or 3 times what you'll pay for just the balsa alone, but it allows you to learn how to really work with balsa. While this L-19 from Uravitch isn't a hard kit to build, there are tricks you learn as you build more and more that really come in handy when you're scratch building. Plus, a good kit like those mentioned above generally require fewer tools to start with - a good knife, a building board, straight edge, some thin pins, etc. When I started scratch building I found myself getting more and more tools - angle finders, spring clamps, weights, etc.

Again this is just my opinion, but my recommendation is to start with a GOOD kit or two, then either try a reasonably easy scratch-build like this L-19 or try building a cheap Hobby King kit (if you want to also learn to swear like a pirate). As bad as the HK kits are, they do really help you become a better builder since you're forced to think three steps ahead, and you're forced to try and figure out what each piece is for, and what order to glue them in. The instructions and cut quality on those cheap kits are horrible, especially compared to kits like Mountain Models sells.

My final thought on the subject, your goal with a first balsa build should be to make a plane that flies, regardless of how pretty it is. An ugly plane with wrinkles and warps that flies OK is far better than a pretty plane that never gets finished.

Fire away with any questions, and when you start a build please consider doing a build thread for it!

 

[DarkFire]

Wow! that was a snappy response time for a 6 month old thread! thank you for that!

I looked at the models you suggested and saw that they both use covering film. Could you point me to a good source for learning about this type of procedure? I, like seemingly all major people in the forums, have about a million projects going on along with school, so the build thread will take awhile to come into existence, but most of my projects are being bumped down the list to accommodate balsa builds now. I also like to say i have a little experience with balsa but all i did was make possibly the world's simplest DLG and then took it apart to improve it and it is just sitting there looking sad. So basically, thanks for the advice to a newbie to balsa!

Thanks again,
Dark

 

[Joker 53150]

No problem, hopefully the info helps you find success with balsa - there is certainly a learning curve, and the trick is to take your time and learn from each build.

Try this link for a massive thread on covering. The first couple posts are the basic how-to's:

https://www.rcgroups.com/forums/showthread.php?t=711624

The first attempts at covering are often somewhat "ugly", but once you gain experience with it you find it gets easier and your results get better. On the L-19s from this thread (both the one I built and my dad's), both are painted and no covering was used. Painting balsa requires a lot of other prep work, sealer for the wood, etc. For many planes this size I think covering gives you a much better finish with a lot less work.

 

[Cobra1365]

Talk about dredging up old posts! I was scrolling thru for a build, randomly putting airplanes that 1) interest me and 2) we don’t see much of. I put in O-1 Bird Dog Plans and your build popped up.My FiL flew these out of Bien Hoa in ‘65. Here’s his pic.... He’s back row, just left of the prop as you’re looking at it.

He flew with the 19TASS from Jan to May 31 (His Bday) when he was hit while calling in a strike. He was evac’d out and finished his career in larger act (C-47, C-141 and finally C-5).

So, the Bird Dog has a personal connection for me. Plus, it’s just a cool lil airplane!

Great job on the build!

 

[Joker 53150]

Talk about dredging up old posts! I was scrolling thru for a build, randomly putting airplanes that 1) interest me and 2) we don’t see much of. I put in O-1 Bird Dog Plans and your build popped up.My FiL flew these out of Bien Hoa in ‘65. Here’s his pic.... View attachment 169690 He’s back row, just left of the prop as you’re looking at it.

He flew with the 19TASS from Jan to May 31 (His Bday) when he was hit while calling in a strike. He was evac’d out and finished his career in larger act (C-47, C-141 and finally C-5).

So, the Bird Dog has a personal connection for me. Plus, it’s just a cool lil airplane!

Great job on the build!

Thanks for sharing!