Hobby King 1875mm B-17G Flying Fortress V2

[davegee]

Grossman56

Good-lookin' design as well.

The 1/2 sphere is clunky, i.e., it can't be sharpened up easily.

You can bring in several of the the 1/2 spheres and rotate each on top of the other to add more sections and then combine all those into one.

This adds a lot of complexity to the design and high pixel count, however.

Or you can use the Hi-Res Sphere and slice it in half if you need a smoother 1/2 sphere.

Best, LB

While Danger Dan with the sage advice of LB work on a V2 more scale 3D printed version of the Cheyenne turret, I have been busy on the B-17 fuselage itself. Yesterday, I glued on a sheet of .005" white styrene with a hole cut in it pretty much scale to what was on the real B-17s. I had to extend it ever so slightly to be sure the retract would work properly, but otherwise it is pretty scale. The white covering will be painted silver like the rest of the fuselage. This way, none of the non-scale mechanics of the retract system show, yet the covering can easily be removed to service or repair the tailwheel gear if necessary.

Also, I added some aluminum tubing to represent the muzzle flow deflectors that were installed on the ends of the guns on the tail and chin positions. These guns were positioned very close to each other, much closer than the ball and top turret guns that didnt need them installed. The powerful expanding gases coming out of the closer positioned guns caused some interference or instability with the gun next to it, thus the reason for adding them. These aren't painted yet, they'll be matte black.

[Grossman56]

Looks pretty good Dave. At which point did you cut the Steeple Chase tail off? Can you get me the dimensions whee the old met the new?

Grossman56
(Dangerous Dan)

[davegee]

Looks pretty good Dave. At which point did you cut the Steeple Chase tail off? Can you get me the dimensions whee the old met the new?

Grossman56
(Dangerous Dan)

Hi Dan: I measured back from the aft end of the fillet for the horizontal stabilizer to the tip or end of the "pumpkin" turret. On the model it is exactly 5.0 inches (exactly what you stated on a previous email guess!)

I'll attach a photo, it is not exactly at a 90 degree angle, but hopefully you'll see the line where they cut off the steeplechase original tail and where the spliced in the Cheyenne turret assembly.

If it looks like we can pull this off, I might order a second just fuselage only B-17 to use as a spare or part of a new airplane.

If this idea doesn't work out, I can use what I have already completed. But hopefully this idea will work out to add this part of the model. I'll hold off to actually cut off the steeplechase tail until we are a lot closer to a working protoype that looks like we can make this work.

Cheers

Davegee

[Grossman56]

Yes, you can see in post# 99 just exactly where the guy is cutting the original tail off, it looks as if it lines up with the line running under the main window. Now, the pics in post#99 are the prototype installation and in production, it looks like it starts just oft of the H.S. interesting. Very similar to the restored tail section in the video.



Grossman56
(Dangerous Dan)

[Grossman56]

More progress tonight, calling it a night and heading to bed. 3:20am comes awful early.

Grossman56
(Dangerous Dan)

[davegee]

Making great progress on this, Dan. Maybe on Sunday or Monday we can get together with the fuselage to discuss strategy. Let me know if you have any time free on your next set of days off.

cheers

davegee

[Grossman56]

Dang Dave, it looks pretty good!



Grossman56
(Dangerous Dan)

[davegee]

Dang Dave, it looks pretty good!



Grossman56
(Dangerous Dan)

It's really coming along! There are a few minor changes that need to be made on it for scale, but those should be fairly easy to do. But the overall concept is really good. Before I can commit to actually removing the foam tail on the model, we'll need to get a good print and have the correct dimensions for fitting the new Cheyenne (or now, maybe "Cody") turret onto the fuse.

Email me when you have some time so I can come over with the fuse to discuss going forward on this.

Thanks for all your work, this is probably a good exercise to do for both of us!

Cheers

davegee

[quitcherbitchen]

I had made a vacuum formed version for mine. It turned out pretty convincing. all mine burned up when my house burned down. You guys look like your on the right track with the 3D printing. Will watch with interest and hope it turns out.

[davegee]

Oh, NO!!! Were you caught up in the Pallisades fire last year?? In any case, very sorry to hear about the loss of your home. I can't think of many things worse in life than losing that.

At any rate, that was an excellent way to go with the Cheyenne turret mod that you did. I did a trial run at scratchbuilding a turret on the fly with mine, but I learned that the downward curve of the early aircraft sloped down more than the Cheyenne mod did, making my turret too tall.

I think Dan has a good start on designing this for the printer, we'll tweak it a little here and there, and hopefully we'll have a finsihed product that looks acceptable.

Thanks for posting the pics on your model. Wish it was still around to fly!

Cheers

Davegee

[davegee]

Dan sent me the first stl file for this Cheyenne turret today. I have printed one out at 100% size that he started with, and am now printing a larger one at 250% the original size. These will be used as testbeds to nail down the precise size and fitment to make a pretty seamless joining of this 3D part and the rc foame model.

I'm attaching a pic of my first attempt at a scrachbuilt Cheyenn turret, just to see how it generally looks. One of the problems just adding on parts on the fuselage for early pre-Cheyenne turret mods is that it makes the turret glass look too tall. That's why if we are to do this successfully, we need to come out with a very close fit to the original foam model when we chop this tail off. I could live with this first attempt on mine if I had to; it doesn't look too bad from a distance but it is definitely not quite right or scale to what I'd like it to be.

We'll press on...

Cheers

Davegee

[Elbee]

davegee

Welcome to the wonderful world of scale compromise and 3DP designs.

I am sure you'll work it all out for the best outcome possible.

Your scratch built part looks quite good actually and certainly defines your intent.

I like it.

Best, LB

[davegee]

Thanks, Elbee. I think it will be a fun and educational project for both Dan and me. Worst case, I can keep the mod I did for the V2 B-17, but I’d prefer to get a good and scale printed Cheyenne turret, if possible. This will probably be a wintertime project, so no rush getting obstacles resolved in a quick manner if it’s just going to take time to do so.

Cheers

davegee

[quitcherbitchen]

looks pretty good. I have a bunch of Cheyenne production factory pictures somewhere in a hard drive. If I find it I will post them.