scale-parkflyer.de depron Beriev BE-200(Beer bomber) 70mmx2 Build

Wingnutz · January 21, 2020, 08:12:12 PM

I still want to build a CL-215 (round engines rule!) but for now, a model of a Russian plane.
The real one is a twin turbofan powered amphibious water bomber.
Since my two passions in RC are EDFs and floatplanes, this was a natural...I am the moth drawn to the flame.
I purchased the kit from Germany and had it shipped home. I've dragged it with me on vacation (two months) and have started the build.
The model is constructed of depron with a few bits of 1/16"(1.5mm) and 1/32" (0.8mm) ply. I initially bought just the plans and subsequently the depron laser cut parts kit from scale-parkflyer. I'm glad I sprung for the parts kit...the number of parts is staggering and the precision of laser cut depron parts is both a treat and a challenge.
Wingspan is approx. 64"(1600mm) fuselage roughly 55" (1400mm) and the plan calls for 2x 70mm edfs on 3S for power. I've already decided to go with 4S and hope I don't regret that change.
Scale-parkflyer provides assembly instructions on-line but they're in German! 😳 Google translation leaves a lot to be desired...thank goodness for the pictures!
I've gotten far enough to realize; I have to cut the wood parts myself, several of the tools I need are 1500 mi away at home, the LHS does not have a good selection of large pieces of thin aircraft ply and the coping saw available at the local ACE hardware store is hopelessly coarse at 20 tpi.
But, I like building on vacation...I have ordered a large sheet of 1/16" ply from Balsa USA, finer coping saw blades from the manufacturer and waterproof 9g servos from HK. I like the whooshy sound of 12 blade edfs and have ordered 70mm units and ESCs from Motion.
I've fitted the depron fuse formers, "stringers" upper and lower spines together and cut the rear fuse/wing-saddle ply former using the finest blade I could find but it took a l o n g time and the cut edges are ragged. Not much more will happen to fuse or wings luntil the ordered bits arrive.
One photo of the partially assembled fuse, one of the full size and one of the hand cut ply fuse former.

Wingnutz · January 21, 2020, 08:19:14 PM

The laser cut depron pieces arrived in a 9" (225mm)x 10" (250mm)x40"(1m) box which weighed less than 3 lb...most of which was the box.
Except for two, the pieces inside were in perfect shape and the three sheets of depron for covering were in almost perfect condition. I can only begin to guess how long it would have taken to cut these by hand.
Picture shows the box after all the fuse parts had been removed. Other photos, the real thing in action...
I'll work on the tail section while I wait for the ordered bits to arrive...ordered the motors and ESCs this morning

Wingnutz · January 21, 2020, 08:23:48 PM

Sorted out all the small parts according to where they're going to end up on the model. I think the parts were sorted to fit them into a small package for shipping when they arrived.
Used foam safe CA to build rudder and frame up vertical stab. I've left one side of v.stab uncovered so I can install wooden or carbon strip supports, stabilator pivot hard points and stabilator drive. The BE-200 is a T-tail, with a stabilator, so stabilator drive is a little trickier than conventional tail. I'm toying with the idea of driving the stabilator with a Sullivan Golden rod, but still not sure how to connect drive cable to stabilator and not sure how much a stabilator needs to move compared to an elevator. Any thoughts appreciated.

Wingnutz · January 21, 2020, 08:29:48 PM

Besides sticking my fingers to the model, CA on my fingers defeats iPad fingerprint recognition! Grrr!

Frank v B · January 21, 2020, 09:09:14 PM

Mr. Nutz,

Great to see you are back at building. I have seen the videos of the Russian water bomber. A weird but effective airplane.
Great to see you are continuing the tradition of beer can/bottles in your build photos.

Enjoy your stay. You stay warm. We will do the freezing for you.

Safe home.

Frank

octagon · January 22, 2020, 12:58:56 PM

Quote from: Wingnutz on January 21, 2020, 08:23:48 PM
Sorted out all the small parts according to where they're going to end up on the model. I think the parts were sorted to fit them into a small package for shipping when they arrived.
Used foam safe CA to build rudder and frame up vertical stab. I've left one side of v.stab uncovered so I can install wooden or carbon strip supports, stabilator pivot hard points and stabilator drive. The BE-200 is a T-tail, with a stabilator, so stabilator drive is a little trickier than conventional tail. I'm toying with the idea of driving the stabilator with a Sullivan Golden rod, but still not sure how to connect drive cable to stabilator and not sure how much a stabilator needs to move compared to an elevator. Any thoughts appreciated.

Hey Bill, looks good. Re: the golden rod. How about running the rod up the space in the forward edge of the stab and simply fashion some attachment to the bar at the forward rod connecting stabilator halfs? Perhaps that rod could be a piece of copper with an eye of some sort soldered to it, to which the cable of the golden rod would in turn attach. Obviously it has to be permanent and secure, as getting to it after the stab is finished would require surgery of the depron.

sihinch · January 22, 2020, 01:48:12 PM

This looks amazing Bill. Fabulous build.

Wingnutz · January 22, 2020, 06:06:52 PM

Quote from: octagon on January 22, 2020, 12:58:56 PM
Quote from: Wingnutz on January 21, 2020, 08:23:48 PM
Sorted out all the small parts according to where they're going to end up on the model. I think the parts were sorted to fit them into a small package for shipping when they arrived.
Used foam safe CA to build rudder and frame up vertical stab. I've left one side of v.stab uncovered so I can install wooden or carbon strip supports, stabilator pivot hard points and stabilator drive. The BE-200 is a T-tail, with a stabilator, so stabilator drive is a little trickier than conventional tail. I'm toying with the idea of driving the stabilator with a Sullivan Golden rod, but still not sure how to connect drive cable to stabilator and not sure how much a stabilator needs to move compared to an elevator. Any thoughts appreciated.
Hey Bill, looks good. Re: the golden rod. How about running the rod up the space in the forward edge of the stab and simply fashion some attachment to the bar at the forward rod connecting stabilator halfs? Perhaps that rod could be a piece of copper with an eye of some sort soldered to it, to which the cable of the golden rod would in turn attach. Obviously it has to be permanent and secure, as getting to it after the stab is finished would require surgery of the depron.

Rob,
Thanks for taking the time to offer a suggestion.
While I was supposed to be sleeping last night, my mind was wrestling with how to attach the Gold-n-Rod to the stabilator and I came up with a plan that's a variation on your idea...it'll involve drilling a small hole in a piece of carbon strip which will be a cross bar between the two stabilator halves. I've done several T-tails with an h. stab/elevator configuration, but the stabilator/T-tail is a new problem and I wanted to try something different from the supplier's servo in the rudder/wooden pushrod configuration. I've opted for slightly bigger EDFs than recommended and since they sit slightly behind the cg, any weight I can remove from the tail will make balancing easier. As soon as my ordered stuff shows up, and I make another visit to the LHS, I'll start building it.
Simon,
Thanks for the kind words...hope I finish this one! I have two other builds started on this forum and they're both back in Bobcaygeon!

Wingnutz · January 22, 2020, 08:42:43 PM

Sorted out the float parts and glued together the two left and two right halves...some serious sanding in the offing. Coping saw blades to arrive next Monday, so slow progress until then...

davidk · January 22, 2020, 09:14:18 PM

And all while doing the crossword... very cool!

octagon · January 22, 2020, 10:12:52 PM

Quote from: Wingnutz on January 22, 2020, 06:06:52 PM
Quote from: octagon on January 22, 2020, 12:58:56 PM
Quote from: Wingnutz on January 21, 2020, 08:23:48 PM
Sorted out all the small parts according to where they're going to end up on the model. I think the parts were sorted to fit them into a small package for shipping when they arrived.
Used foam safe CA to build rudder and frame up vertical stab. I've left one side of v.stab uncovered so I can install wooden or carbon strip supports, stabilator pivot hard points and stabilator drive. The BE-200 is a T-tail, with a stabilator, so stabilator drive is a little trickier than conventional tail. I'm toying with the idea of driving the stabilator with a Sullivan Golden rod, but still not sure how to connect drive cable to stabilator and not sure how much a stabilator needs to move compared to an elevator. Any thoughts appreciated.
Hey Bill, looks good. Re: the golden rod. How about running the rod up the space in the forward edge of the stab and simply fashion some attachment to the bar at the forward rod connecting stabilator halfs? Perhaps that rod could be a piece of copper with an eye of some sort soldered to it, to which the cable of the golden rod would in turn attach. Obviously it has to be permanent and secure, as getting to it after the stab is finished would require surgery of the depron.
Rob,

Thanks for taking the time to offer a suggestion.
While I was supposed to be sleeping last night, my mind was wrestling with how to attach the Gold-n-Rod to the stabilator and I came up with a plan that's a variation on your idea...it'll involve drilling a small hole in a piece of carbon strip which will be a cross bar between the two stabilator halves. I've done several T-tails with an h. stab/elevator configuration, but the stabilator/T-tail is a new problem and I wanted to try something different from the supplier's servo in the rudder/wooden pushrod configuration. I've opted for slightly bigger EDFs than recommended and since they sit slightly behind the cg, any weight I can remove from the tail will make balancing easier. As soon as my ordered stuff shows up, and I make another visit to the LHS, I'll start building it.
Simon,
Thanks for the kind words...hope I finish this one! I have two other builds started on this forum and they're both back in Bobcaygeon!

Another idea occured to me Bill. (Frankly I love the challenge of designing something that does not exist yet). Instead of drilling a hole in the carbon, how about using a carbon rod the same diameter as a ball link. You could slip the ball link over the carbon rod, thereby not risking weakening it with a hole. Then solder a brass threaded adapter to the end of the golden rod cable and screw it into the ball link. I built a Sagita sailplane 2 winters ago. It has a full flying tail similar to your water bomber, although the stabilator is only 1/2 way up the vertical stab. That kit came with the hardware to do what I have suggested with the ball link.
Anyway Bill, as with any free advice, take it for what it is worth. Good luck with the build. I will very much look forward to seeing it fly when you are finished.
Cheers, Rob

Wingnutz · January 23, 2020, 08:42:45 AM

Quote from: octagon on January 22, 2020, 10:12:52 PM
Quote from: Wingnutz on January 22, 2020, 06:06:52 PM
Quote from: octagon on January 22, 2020, 12:58:56 PM
Quote from: Wingnutz on January 21, 2020, 08:23:48 PM
Sorted out all the small parts according to where they're going to end up on the model. I think the parts were sorted to fit them into a small package for shipping when they arrived.
Used foam safe CA to build rudder and frame up vertical stab. I've left one side of v.stab uncovered so I can install wooden or carbon strip supports, stabilator pivot hard points and stabilator drive. The BE-200 is a T-tail, with a stabilator, so stabilator drive is a little trickier than conventional tail. I'm toying with the idea of driving the stabilator with a Sullivan Golden rod, but still not sure how to connect drive cable to stabilator and not sure how much a stabilator needs to move compared to an elevator. Any thoughts appreciated.
Hey Bill, looks good. Re: the golden rod. How about running the rod up the space in the forward edge of the stab and simply fashion some attachment to the bar at the forward rod connecting stabilator halfs? Perhaps that rod could be a piece of copper with an eye of some sort soldered to it, to which the cable of the golden rod would in turn attach. Obviously it has to be permanent and secure, as getting to it after the stab is finished would require surgery of the depron.
Rob,

Thanks for taking the time to offer a suggestion.
While I was supposed to be sleeping last night, my mind was wrestling with how to attach the Gold-n-Rod to the stabilator and I came up with a plan that's a variation on your idea...it'll involve drilling a small hole in a piece of carbon strip which will be a cross bar between the two stabilator halves. I've done several T-tails with an h. stab/elevator configuration, but the stabilator/T-tail is a new problem and I wanted to try something different from the supplier's servo in the rudder/wooden pushrod configuration. I've opted for slightly bigger EDFs than recommended and since they sit slightly behind the cg, any weight I can remove from the tail will make balancing easier. As soon as my ordered stuff shows up, and I make another visit to the LHS, I'll start building it.
Simon,
Thanks for the kind words...hope I finish this one! I have two other builds started on this forum and they're both back in Bobcaygeon!

Another idea occured to me Bill. (Frankly I love the challenge of designing something that does not exist yet). Instead of drilling a hole in the carbon, how about using a carbon rod the same diameter as a ball link. You could slip the ball link over the carbon rod, thereby not risking weakening it with a hole. Then solder a brass threaded adapter to the end of the golden rod cable and screw it into the ball link. I built a Sagita sailplane 2 winters ago. It has a full flying tail similar to your water bomber, although the stabilator is only 1/2 way up the vertical stab. That kit came with the hardware to do what I have suggested with the ball link.
Anyway Bill, as with any free advice, take it for what it is worth. Good luck with the build. I will very much look forward to seeing it fly when you are finished.
Cheers, Rob

Rob, if we keep quoting each other, one post will soon take up a whole page!
I really like your latest idea. The threaded shaft in the Gold-n-Rod is 2-56 and Du-bro makes a ball joint with 2-56 threaded shaft...cost, $1.98.
I'll only have to spend $98.02 to get free shipping!

piker · January 23, 2020, 11:24:59 AM

Hey Bill! This project is Awesome! So cool. I'll be watching with huge interest!

Wingnutz · January 23, 2020, 02:07:34 PM

Thanks Rob,
It'll be slow, and I'll have to wait until we're home to finish...in one piece, it's too big to go in the car with all the stuff from our stay!
Rough "carved" the float halves using an Olfa utility knife. I'm convinced the black blades are sharper than #11 hobby knife blades.
Sorry davidk, the crossword's not done...yet!

Wingnutz · January 24, 2020, 06:01:24 PM

Using Rob D.'s idea, I put the stabilator drive together. Sullivan Gold-n-Rod, Du-bro ball link, aluminum tube and carbon rod. Picture shows one half of the stabilator and the v.stab with one skin removed.
There're no hard points for pivots yet, but it still seems to work.
https://youtu.be/5qY0Jnm5OQw