Hi all -

Well with a few months of winter remaining here in Montana, I needed a new project. So here we go! Just got my Bill Hempel Extra 300L in a custom Red Bull scheme - man is it beautiful - and enormous! I'll be mounting a zdz 420 quad on the front end of this thing with a 36/16 3-blade prop.

The quality of this model is spectacular and Bill is great to work with. The pictures below really don't do it justice. Nor do they really convey the sheer size of this beast.

Anyway, I hope y'all will follow along, help me build this thing (its really not "building", I know) -any suggestions are always appreciated!

Very nice.

wow subscribed!

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Nice project!

What type of electronics will you be running? Interested in the requirements for servos, wiring, batteries, etc. for something this size.

Thanks for the comments all! Some details of the build - 4 servos per aileron, 2 per elevator. Hoing to run Hitec 7950's unless I start getting the "jitter problem". There is another thread on that subject, so I won't go into it but I'm hoping that the powerbox and the signal boosters I plan on using solve any problems. Heck, I have the servos . . . might as well use them. Going to run a Seiko on a 3-cell lipo for the rudder.

Bill H. designed this thing with hatches in the wings where I could install an entirely separate receiver and battery for each wing half. I'm using a Powerbox Royal Spektrum receiver, but I might still do that to avoid voltage issues, but then I'd have to use a matchbox for servo matching and setup of each wing. We'll see when I get to it. I'm going to try a more traditional setup first and see if it works. I usually make my own extensions from 22 guage wire. This time, I think I'll run power on heavier wire as a power buss for each wing so there's less voltage drop.

I'm going with my first HV setup with this airplane. Power will be from 2 7800 mah ThunderPower 7.4 lipos. Ignition batteries will be li-ion. I've been using the Booma RC "iggy" switches for my other planes with great success, so I'll use them here as well. They are both a switch and remote kill as well. Really nice product. I also have the Intelliswitch on another rig and it works great.

I'll post pics of todays progress shortly.

C

Mounted the main gear today. The bolts that came with it looked waaaaay too small, so I beefed them up to 1/4-20. There were wheel cuffs that came with the airframe. Took a little dremeling to make them fit right. In the end, I added the black casing (stripped it off of some wires) to neaten up the install.

Got the engine mounted today as well. I can't find a mounting template for the zdz 420 (hard to believe) so I had to make my own. Turned out great. Checked the cowl and looks like the fit is right on. The airframe is designed around the 420 and came with spacers so that the install is perfect.

Some of the pics give a little perspective on the sheer mass of this thing. Still, the airframe is remarkably light for its size. I have a 46% yak running on a 3w 275 and that airframe seems way heavier. I'll get an all-up weight when its done.

Throttle and choke servos are going to be interesting. Got the throttle servo mounted and I think it should work out fine. I was just about to get to the next step when I was called in by the boss to help her with some honey-do's. Can't complain - she is one patient woman.

Sub'd.......Sweet!

Sub'd!

OK, chores are done and got some more accomplished. Mounted the choke servo using a Secraft servo mount. Love their stuff - also used their Ignition Bed mounts, makes for a nice clean install.

Got the exhaust mounted and discovered that the choke servo was kinda in the way, so I moved that. This plane is so big that there's plenty of space to work with!

Dialed in the throttle curve on my new 11x (thanks Dana at Chief!) so that I have a nice linear response on the carb butterfly. I'll probably need to adjust the curve once I get the engine running. Really easy radio to program.

Next, I need to figure out how I'm going to support the cans.

subed

Awesome!!

That thing makes the Mini Cooper look, well Mini.

Very nice. Think the three blade will keep it "quiet"?. also, the pipes on the bike look like they would fit about right!