Dumas L-19 Bird Dog

[roversgonemad]

This one isn't nearly as big as Joker's. It will also only weight about 10 oz. It's far enough along now to post pictures. If I have learned one thing, posting pictures of a balsa build will stall it forever, at least for me.







I still need to get the speed control soldered up, and then get the elevator and rudder controls sorted. Aside from some shaping on the right wing leading edge, and some sanding, the wood work is essentially complete.

I am going for this color scheme:



I already have the vinyl from Callie, and the ultracote lite.

It should be a nice gentle slow flier. It's certainly a lite build! I have broken a few stringers along the way! It's essentially a rubber band plane with a motor and RET controls. Mr. Tritle designs some spectacularly lightweight airframes!

 

[Userofmuchtape&glue]

Wow some great craftsman ship there!

 

[Joker 53150]

Looks great!

 

[jsknockoff]

What motor are you planning to use in it?

 

[roversgonemad]

The motor is the equivalent of the old blue wonder. I think it's a 2213, 1300 kV. On two cell with an 8x3.8 SF prop, it should fly nicely. I may even use a 9x4.7, but that seems like overkill for a sub 10 oz. plane. I am going to use a 2S 500 mAh battery.

Thanks for the compliments. A laser cut kit makes it pretty easy. Pat Tritle's designs are pretty well thought out, so they are a relatively easy build. If you can build a Guillows plane, you can build a Tritle design. It just requires a little patience sanding all the miter cuts for the various diagonals.

I am on business travel this week, so hopefully covering this coming weekend. Maybe even a maiden by Turkey Day.

Edit: the motor is a Turnigy 2730, 1300 kV. I can never remember all the numbers!

 

[roversgonemad]

Well..... The turkey day maiden isn't likely. I need to give the Ultracote Parklite some time to think about its behavior. Clearly, it's not seeing things my way. All the stuff I have heard about the lightweight iron coverings appears to be true with the Ultracote..... That or I just suck, and need to suck less to be successful with Parklite. Monokote, Econokote, UltraKote, Tower Kote, all easy.... Parklite, not my friend.

 

[roversgonemad]

At long last, all but the shark mouth and landing gear spats done! She weighs in at 8.3 oz, ready to fly. I just missed the two sticks of butter.... I guess I'll have to put my FAA number on her. It's spring break for the kids, and I am off the rest of the week. Weather cooperating, I'll maiden her in the next few days. We'll see how Mother Nature treats me; this time of year, in eastern Idaho, she can be pretty fickle!

 

[jsknockoff]

Really nice covering job! I hope it flies well for you.

 

[ranger351]

Great looking plane!

 

[DarkFire]

That is a really nice looking plane, hope it flies well!

 

[Turbojoe]

I can only dream about an L-19 like Jokers but this Dumas kit could be within my grasp. It could be a nice companion to my Mountain Models/Dave Blum Cessna 180. Yours is looking good!

Joe

 

[Turbojoe]

And as luck would have it I just grabbed a Dumas L-19 kit on RC Groups for $50.00 shipped. Not an astounding price but one I'm happy with. I'm actually a little bored working on my Telemaster 40 so I think it's going back into the dark nether regions of the back room again so I can build something new.

Joe

 

[roversgonemad]

Be picky about your stringers. If I build another one, I'd probably replace most of the Dumas stringers. I used all the wood from the kit, and some of the stringers were really soft.

 

[DarkFire]

what thickness are the stringers?

 

[Turbojoe]

Be picky about your stringers. If I build another one, I'd probably replace most of the Dumas stringers. I used all the wood from the kit, and some of the stringers were really soft.

I have an order of 48 1/8"x1/8"x24" basswood stringers on the way from Tower Hobbies. They have been on back order forever but just released and should be here Monday. I've learned my lesson with 1/8" balsa stringers. Was planning to build a second MM Cessna 180 but will do the L-19 instead. AFTER I build a much updated MM Urban Flyer.

Joe

 

[roversgonemad]

The stringers are mostly 1/16". I have one of the master airscrew strip cutters. I have found that it's hard to get good stringer consistency, so I buy sheets and cut my own.

 

[Joker 53150]

The stringers are mostly 1/16". I have one of the master airscrew strip cutters. I have found that it's hard to get good stringer consistency, so I buy sheets and cut my own.

When I set mine up like they show in the instructions I had problems with the blade wandering a bit. Online I found a couple tips which really helped make it work much better. First, I took an old #11 blade and broke off about 1/8" from the tip. This blade was then mounted along with the good blade (shorter blade to the outside, if I remember correctly), and having it there stiffens up the main cutting blade. Second, I raised the cutting blade up a bit for most thicknesses. I'll cut from one side, then flip the sheet over and finish the cut. It's more work, but gets me good results. On the very thin stuff I just do it in one cut.

It's not perfect, but the results are good enough that I don't buy many balsa sticks anymore.

 

[roversgonemad]

I get good consistency from my cut stringers. I also cut from both sides. It's the stringers in the bin at the hobby shop that aren't consistent, that's what I meant, poor wording on my part. I've really liked having the stripper. It does have its quirks, but it's a super economical solution

 

[Turbojoe]

My stripper is reinforced too. But 1/16"? With my fingers I don't know. This and the Taylorcraft may be resold. I have enough trouble not breaking 1/8" stringers.

Joe

 

[roversgonemad]

Tritle planes are basically free flight rubber planes with electric motors. They are fragile little planes, but they fly soooo sloooowwww!