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1:9 Scale B-17G - 'Sweet Pea'

PsyBorg

Wake up! Time to fly!
Mentor
Cool you got more exposure from that article. Well deserved with what you guys are going thru to buikd AND document the process for others to learn from.

An idea for cable slack management could be easily done with a 3d printer. Modified mini shocks that use pen springs and have pulleys on the ends. One or two of those per side will ensure you never get a kink or bind when using the tail wheel system.
 

wilmracer

I build things that fly (sometimes)
Mentor
Lots of interesting ideas to mull over. I kindof like the the shadow box idea, although it would probably be one big box to cover both gun positions (they were side-by-side on early B-17s but then got staggered by the time the G model came around so the wait gunners had more room to move). I'll do a bit of experimenting to come up with a lightweight solution. Maybe even just lay up a piece of 1oz glass cloth to make fiberglass sheets and cut the walls/floor out of that. I won't be doing any serious detailing with it now, but it would be a lot easier to go ahead and paint this area the appropriate OD / interior green BEFORE closing up the model.

Nothing got done last night. Feel a bug coming on and went straight to bed after the kid went down. We'll see how tonight goes :)
 

rockyboy

Skill Collector
Mentor
Lots of interesting ideas to mull over. I kindof like the the shadow box idea, although it would probably be one big box to cover both gun positions (they were side-by-side on early B-17s but then got staggered by the time the G model came around so the wait gunners had more room to move). I'll do a bit of experimenting to come up with a lightweight solution. Maybe even just lay up a piece of 1oz glass cloth to make fiberglass sheets and cut the walls/floor out of that. I won't be doing any serious detailing with it now, but it would be a lot easier to go ahead and paint this area the appropriate OD / interior green BEFORE closing up the model.

Nothing got done last night. Feel a bug coming on and went straight to bed after the kid went down. We'll see how tonight goes :)
1oz glass cloth sheet walls sounds like a great idea to me! Lightweight, will take paint well, and doesn't care about NoVA humidity :D

Feel better soon - there are some sucky "take you out of commission for a week" bugs running around here this month.
 

wilmracer

I build things that fly (sometimes)
Mentor
Not much progress on the 17 last night, but I did shoot a video on the method I use with Fusion 360 to create the instrument panels. At our next local AMA club meeting we're going to be discussing using Fusion 360 and 3D printing to make scale parts for our models and I'm going to do a demo during the meeting. I wanted the guys in our club to have a video they could go back to for reference so they can try it out for themselves. As an incentive I'm going to offer to print panels for any club member who designs one for their model. They just have to send me the file and be patient


Its a long video but if anyone hasn't tried Fusion 360 before and wants to have a go at it this is an easy way to start.

 

jaredstrees

Well-known member
Awesome, always looking to learn, and I have this wonderful 3D printer, but so far have only printed files from thingiverse, etc. Sooner or later I'm going to need to make my own specific parts!
 

wilmracer

I build things that fly (sometimes)
Mentor
Glad some folks will get some use from the video! Panels were the first things I tried designing in sketchup and then in Fusion 360 and if you're patient you can get beautiful results with just a few simple techniques.

Had a presentation today to prepare for so no B-17 building got done last night. Tonight is V-day and tomorrow we have a sitter for date night, so I doubt I'll get much shop time before Saturday.
 

wilmracer

I build things that fly (sometimes)
Mentor
So its been a minute without a meaningful update on the Sweet Pea, but progress is being made again. I had to spend 5 or 6 hours cleaning the shop over the weekend, but it is clean and I'm able to move around again which helps a lot. I also have a little side project for a buddy's build that will hopefully be done in a few days but it isn't taking up too much time.

After mulling over the floor/walls I decided to KISS for now. What I want to avoid is having the white and pink/purple-ish foam visible when you look in the waist gunner windows (or through the other small windows/ports) I'll leave the ultra-detailed aft interiors to the plastic model guys. When I cut the waist gunner windows in I'll add enough detail to catch your eye but what I opted to do now was just make the interior of this section black. I used 2mm foam to make a floor and a forward and aft wall. I tested a few paint options but what I ended up doing was attacking this interior area with giant Sharpie markers. It took 3 passes over the white foam areas to get them really dark, but I think it will work out really well and there was no measurable weight gain from the sharpie. The only light getting in will be from the windows so as long as it stays dark I can hopefully hide the fact that the interior isn't right.

In related news, after conversations with @willsonman and @rockyboy I decided I wanted to pick up a Horus 10S and start playing with it and setting up the programming and mixes. I've been a Specktrum guy since I got back into the hobby and I'm always nervous to make a change when something is working, but this bird will need a LOT of channels. I've heard nothing but good things about the reliability and functionality of the Horus so I'm going to give it a shot. As luck would have it @rockyboy was at the AMA expo over the weekend and found a GREAT deal on one, so he picked it up for me. THANKS SO MUCH! Can't wait to get my hands on it and start playing.

Off the top of my head I think I'll need the following channels for the pilot radio.

1 Elevator 1
2 Elevator 2
3 Rudder
4 Tail retract
5 Tail steering
6 R main retract
7 L main retract
8 R flap
9 L flap
10 R aileron
11 L aileron
12 Engine 1
13 Engine 2
14 Engine 3
15 Engine 4
16 Bomb door
17 Bomb release
18 Sound System (link to throttle but want to be able to shut down in flight or run w/o motors)
19 Lighting on/off

I'd like to be able to do bomb drops with or without a co-pilot on a separate radio. The bomb bay doors and drop may end up on another radio along with turrets, but that is TBD. I'll probably play with running redundant receivers and run inboard motors + 1 elevator & 1 Aileron on one and Outboard motors + 1 elevator & 1 Aileron on the other. That way loss of a single receiver leaves me with flight controls and 2 engines. Electronic setup and config will be a rabbit hole for another day though...
 

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willsonman

Builder Extraordinare
Mentor
The first thing you are going to want to do it ditch the stock OS and go to OpenTX. Don't worry, It's pretty easy and I can walk you through it one weekend. I do have a module that can expand you to the the max 32 channels but once we get to that point we can more seriously consider it. In the meantime... I would recommend you head on over to Aloft Hobby and order a hard case. After carrying mine around in the soft case I did miss that hard one. Also, that soft case does not protect the switches.
https://alofthobbies.com/frsky-horus-x10-travel-case.html
 

rockyboy

Skill Collector
Mentor
The sharpie worked nicely on the interior!

I can go ahead and flash the latest OpenTx firmware to the Horus before I deliver it.

Also suggest you might want to pickup this book from Aloft as a physical reference while you're getting up to speed on OpenTx https://alofthobbies.com/horus-x10x10s-opentx-user-manual.html

If you want to grab a receiver while you're filling the cart, the one you'll need is the X8R
https://alofthobbies.com/frsky-x8r-8-16-channel-receiver.html

and at least of these too
https://alofthobbies.com/frsky-sbus-decoder.html

And a servo channel changer to program the sbus decoder
https://alofthobbies.com/frsky-servo-channel-changer-sbus-cppm.html

Good overview of using sbus decoders over here: http://boltrc.com/blog/tag/how-to/
 
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Very good choice going to the X10S!

If you're going to be using the SBUS setup and want to also use a redundant receiver, I would suggest either the RX8R, or RX6R (Aloft only has the RX6R in their stock). These allow you to use satellite receivers for redundant signal paths.

https://alofthobbies.com/frsky-rx6r.html

I second the SBUS decoder recommendation also.
 

willsonman

Builder Extraordinare
Mentor
John, I've been using the RMILEC converter with excellent success. Breaks out into all 16 channels in one pop. THe other thing is you can use the X6R OR the XSR-M... Not that the weight of a full X8R will be much of a concern but as long at there is an S.Bus with the full 16-ch duplexing... you are golden. I used a X6R in the Corsair and I'm running a X8R in my P-47 just because I was trying to NOT use more than 8 channels but ended up needing more... I get carried away sometimes :p

https://www.ebay.com/itm/RMILEC-Mul...al-Converter-Signal-Analyzer-V3-/292539484941
 

rockyboy

Skill Collector
Mentor
John, I've been using the RMILEC converter with excellent success. Breaks out into all 16 channels in one pop. THe other thing is you can use the X6R OR the XSR-M... Not that the weight of a full X8R will be much of a concern but as long at there is an S.Bus with the full 16-ch duplexing... you are golden. I used a X6R in the Corsair and I'm running a X8R in my P-47 just because I was trying to NOT use more than 8 channels but ended up needing more... I get carried away sometimes :p

https://www.ebay.com/itm/RMILEC-Mul...al-Converter-Signal-Analyzer-V3-/292539484941
Wow - that RMILEC unit looks great! Think I need to order one of those for the "box of spare parts" :D

Depending on layouts, the FrSky sBus units might be handy to have a single wire connection to a wing for instance or back to the tail to simplify wiring, but the RMILEC unit is a good bit cheaper than 4 FrSky ones to get the same number of channels broken out.
 

wilmracer

I build things that fly (sometimes)
Mentor
Thanks guys! Various goodies above have been ordered. As for the case I might look for something that could accommodate my DX9 and chargers as well. I'm not going to swap everything over to the 10S so I'll be hauling both around for the foreseeable future.

So... this morning I saw a sale on a 1875mm B-17 model that has a pretty good following on one of the other forums. I picked one up and will be using it as a test bed for the Horus and for various programming options. I also want to get some 4 engine stick time under my belt. I have a fair amount of time on twins but no time on big bombers so I'll get as much stick time on this and hopefully get really comfortable with a 17 before the Sweet Pea is airworthy. Tonight I'm in the shop sheeting up more of the fuse. :)
 

rockyboy

Skill Collector
Mentor
Thanks guys! Various goodies above have been ordered. As for the case I might look for something that could accommodate my DX9 and chargers as well. I'm not going to swap everything over to the 10S so I'll be hauling both around for the foreseeable future.

So... this morning I saw a sale on a 1875mm B-17 model that has a pretty good following on one of the other forums. I picked one up and will be using it as a test bed for the Horus and for various programming options. I also want to get some 4 engine stick time under my belt. I have a fair amount of time on twins but no time on big bombers so I'll get as much stick time on this and hopefully get really comfortable with a 17 before the Sweet Pea is airworthy. Tonight I'm in the shop sheeting up more of the fuse. :)
Sweet deal! :p

I flashed the latest stable OpenTx 2.2.3 to the Horus last night and put the default SD card contents in place for you. If you want to get started on the programming side before the radio arrives, install OpenTx Companion software from http://www.open-tx.org/2019/01/06/opentx-2.2.3 and setup a radio profile to start playing with the simulator. Also, any models you create in Companion can be loaded to the Horus so no work is wasted - my usual workflow setting up models is to create them first on the computer with Companion, then load them into the transmitter and do final tweaking bound to the receiver on the plane (servo reversing, setting end points, adjusting mixes, etc).

I'll let @willsonman share default models to begin with as his will be coming from a Horus with the same switch layouts. I'm happy to provide a second wave of sample models, but since they will be coming with a Taranis switch layout perspective I might be doing things a little differently that work best on the Horus. Might as well start with the best foot forward. :D
 

willsonman

Builder Extraordinare
Mentor
Hey now... my foot is still healing. It may not be the best foot but it's still a good one. :p

Yeah, I tend to just setup something default for my bigger builds. Then as I build things out I test fit them and setup the programming. When the model is ready to my satisfaction, I then go to the computer and backup the entire radio.