L-19, 27% from Hostetler Plans, 116" span

[Joker 53150]

The landing light is actually in the port wing on the L-19. I'll need to order a housing for it which is supposed to really brighten it up, and I'll also get the lens covers for the red/green nav lights at the same time. The tentative plan is to program the landing light so it goes on with the flaps, although it could be controlled by a separate channel if I've got one available. I'm still kicking ideas around for how all the lights will be controlled and powered, and since there is a ton of room in this plane I'll probably just add a small battery pack to power them so I'm not drawing juice from the receiver pack or the ignition battery. Dang, three different batteries in one plane...!

 

[willsonman]

I've seen as many as 4. 2 ignition batteries (redundancy), 1 Tx, 1 flight controller. This is on an IMAC airplane for competition. When you run 3 digital servos on one aileron you need the control board to isolate the throw of each servo so that they do not fight each other and kill the servo or send feedback into the Rx. THe controller also regulates the voltage so under heavy load the voltage will not sag. They run about $200 but these airplanes are generally not cheap by any means. in the $2-5K range. Some even more.

 

[Joker 53150]

Crazy stuff. I'll have one for the receiver and servos, one for the ignition, and one for the lights. There should be enough room in the nose for all of the batteries, the gas tank, and the servos for throttle & choke.

On a different note, yesterday I was doing some more work trying to figure out how I was going to route the lines to the tail, and I found my entire head could fit inside the door opening and into the fuselage.

 

[TexMechsRobot]

Crazy stuff. I'll have one for the receiver and servos, one for the ignition, and one for the lights. There should be enough room in the nose for all of the batteries, the gas tank, and the servos for throttle & choke.

On a different note, yesterday I was doing some more work trying to figure out how I was going to route the lines to the tail, and I found my entire head could fit inside the door opening and into the fuselage.

pics or it didn't happen.

 

[Joker 53150]

The new powerplant arrived today, a Turnigy 58cc to replace the Quadra 50cc. The Quadra had the ignition coil and large rotating flywheel, while the Turnigy is a more common style that uses an electronic ignition (not shown). The carb sticks out quite a bit more than the Quadra, to the point where it'll probably stick out the side of the cowl a bit as I'm not sure I can change that. The exhaust also dumps down the side exhaust instead of the rear exhaust setup on the Quadra. I may be able to get a Pitts-style exhaust to change that, but haven't looked yet. Plenty of time to worry about that!




So besides being more compact, the Turnigy is also a bit lighter. Here's the Quadra tipping the scale at 2499 grams (about 5.5 POUNDS). No prop, no gas tank, just the dry engine.




Compared to the Turnigy's weight of 1900 grams (about 4.2 pounds). Again, this is just the dry weight. I added a 2200mAh 3 cell battery into the pile to account for the battery I'll need to run the ignition system, and it is still a pound lighter than the Quadra. At this time I have no idea if I'll need to add that extra weight back in to make the plane balance, so the weight savings may not matter much.




The servos for the elevators were also installed so I can work out the details on the final locations for the pushrods.




Challenge accepted, my big melon inside the fuselage via the door. I guess you could say this fuselage has plenty of headroom? Sorry about that...

 

[jsknockoff]

I wasn't aware that Turnigy had a line of gas engines. Learn something new every day.

 

[Joker 53150]

Testing the navigation lights I got from Electro Dynamics.

 

[willsonman]

Perhaps I'm showing my ignorance (gasp!), but if that is a 2-stroke gas engine, why can't you just turn the head 90 degrees and run pipes off the muffler? That prop extension looks pretty long off the main shaft.

 

[Joker 53150]

I believe some are designed so that you can rotate the cylinder head, but can't confirm that would be possible in this case. Are you thinking of rotating it to put the muffler behind the jug like the Quadra has? That would put the carb in front where it may hit the prop. Rotating it the other way would have the exhaust out the front of the engine which might work if I could run an exhaust pipe back down and out the back, but then the carb would be sticking through the firewall by about 3 inches.

The prop shaft extension is fairly long, but that was a selling point for me as it'll help everything stay clear of the cowl (unlike the Quadra's flywheel). I haven't taken it apart to verify, but it looks like it's got an extension similar to what I was considering having made for the Quadra.

 

[willsonman]

Yeah, I was thinking with the carb through the firewall. I've seen that done before where folks want non-turbulent air in the mix for better reliability. Not sure if it works for that but its what they said.

 

[Joker 53150]

More work on the control surface components. I'm using a combination of pieces from DuBro and Robart to make it all work as wanted. The control horn is Robart and the pull-pull wire and connecting post and wire is from DuBro. Some day I'd love to get a full assortment of various connectors and pieces like this to have on-hand for just such a need.

So the wire is run through the threaded post and is looped around a small piece of tube and crimped. Nice and secure, and the threaded end gives me a little extra room to tighten it up if needed.




A small piece of shrink tube covers it up and this piece is ready to install.




Here is where things got "fun", as this area has been giving me headaches for a while as I try and get everything lined up for smooth operation. I needed to get four individual pushrods to exit the fuselage in a small area and not interfere with each other. Once the fuselage is fiberglassed I'll trim off much of the exposed pushrod sleeves, but for now it all keeps things lined up properly.




A while back I posted a picture of a large cut-out made for the pushrods, and now I'm filling that area back in. It's all very rough at this time, but balsa filler and sand paper will take care of that soon enough. The pushrods were left alone and I filled in around them in an attempt to let them run as straight as possible. Note I'm doing something a little different with the pull-pull cable, I'm running it through a pair of small pushrod sleeves. This will allow the pushrod to more easily slide through the fuselage as it won't get hung up on anything




Once the fiberglass is done I'm planning to trim these pieces to fit over the hole in the fuselage, to give it a more authentic look.

 

[willsonman]

Those fairings are a great idea! Looking very clean.

 

[wilmracer]

Looking really good. The fact you can get your whole head in there really shows how big this thing is

 

[Joker 53150]

'Tis surely a melon of gargantuan proportion!

When I'm not carting my head around in a giant sling to take pressure off my neck I continue to push forward with the fuselage work. Word just came via e-mail that the wing has been laser cut and should be here in a few days, so I gotta keep moving!

Since the pushrods are routed I can finally finish planking the fuselage. The top has been open allowing me access, so time to close it up. As usual, the planks look a bit rough but will clean up nicely with some filler and sanding. As mentioned a while back, I love these pins! Very sharp, and the yellow "barrel" make them easy to grab.




With the glue dry the pins come out and I can do some shaping around the rear window opening. The right side will be next, and then attention will be turned to the guts, getting the fuel tank mounted, servos for throttle & choke, battery location, etc. Once that's done I can start on the wing.

 

[jsknockoff]

It's really looking great! I'm jealous, I really want to go big on a build soon. That top sheeting section reminds me of a strip canoe.

 

[Joker 53150]

Careful, building big can be addictive!

 

[jsknockoff]

Yeah I know, when I took a break from RC giant scale was the only stuff I had. They really chew up some cash though.

 

[Joker 53150]

True, although electric planes can still be reasonable until you get into the really big or the faster stuff. The Astro-Hog and 1/4 scale Pietenpol I built recently aren't bad, but a big gasser can certainly increase the expected expenses! When I eventually get to build the Sig Kadet Senior I'll probably build it around the same battery used on the Hog and Piet so I can avoid having to buy all new batteries for one plane.

 

[Joker 53150]

Distractions, distraction, and more distractions!

I went to a swap meet with my dad in Green Bay over the weekend, and I saw something I couldn't pass up, a 1/6 scale Stinson Reliant with an 84" wingspan for $75. The seller didn't know much about it, as he didn't build it and it's never flown. There were no electronics inside, but it did have a nitro motor. All the important stuff was there, although there were a few tears in the covering and the builder didn't bother sanding the balsa blocks by the vertical stab, so it looks like it's hunched-backed. Nothing major, and the seller accepted $70. It's a big bird, qualifying as Giant Scale (mono-wing planes over 80" span). It's about a foot shorter than my 1/4 scale Cub and quite a bit smaller than the L-19. It'll have a nice presence at the flying field.

After getting it home and really looking it over, I'm convinced this was built for display and not for flying. None of the control surfaces moved as all the hinges were glued across the pins or the pushrods were coated with epoxy inside the fuselage so they couldn't move. No servos were ever installed as there are no screw holes. Also, there was a fuel tank for the nitro motor inside the fuselage, but there was absolutely no access to the inside of the fuselage to install servos, receiver, or even to fill the tank! The wings also had no servos and the servo pockets were completely covered over and invisible. Covering on the wings was pretty nice, and I like the color combination of red/silver with white pinstripe.

After some searching online I found this is an old Robin kit, a pretty well regarded company that has since changed hands. Hopefully I can find plans for it, although they shouldn't be required for what I'm planning.

So basically there was no visible way to get the electronics installed without surgery and there were flaws that needed to be corrected, so I took an hour to strip most of the covering off to see what kind of condition the structure is in. Surprisingly, it's very nice. Somebody who knew what they were doing built this plane (the hunched back portion not included). It's extra-ugly right now stripped down, but that'll be easy to fix with new covering after I create an access hatch and stuff some guts into it. I'm still debating if I want to go electric or gas with it, but that's not a big deal right now as the L-19 wing short kit should be here soon and I want to get started on that!










Going back to the nitro engine that was in it, it was a Super Tigre 90, which means nothing to me. It looked like it was new & never used, but the carb was gummed up. I posted on FaceBook for advice - do I clean it or leave it as-is when I sell it, as I know squat about nitro. I got some good advice and plenty of "internet advice", plus a couple guys messaged me about buying it. I looked up what new versions of this motor sell for, but this is an older one made in Italy and not in China, so evidently it's more valuable. I pleaded ignorance and said "Make me an offer", expecting $25 or so. Well, I got stupid-lucky as the motor more than paid for the plane and my gas bill driving 4 hours round trip. I'm really looking forward to finishing up the Stinson and getting it airborne!

 

[Turbojoe]

Dayam! Why don't I ever get that lucky? I've gotten a few decent deals but nothing like THAT!

Joe