Official FMS 1500mm P-47D Razorback Thread

[Elbee]

Elbee,Do you feel a 3d printed hub would be strong enough to withstand the stress of a spinning propellor. It's a concern to me that it doesn't cause an accident to someone. Hesitant to have a HS class be put in that position.Best Regards, Rex

Rex,

The simple answer is no......but.....

The centrifugal forces are fierce at the prop hub under load.

That on record, nothing beats a failure than a try.

Print wise, I think it can be done as long as the hub is simply eye candy and the mechanical structure (for lack of a better term) is solid.

I thought about trying something similar with the Corsair as the prop is rather large.

The loads even in twist would be great as the prop bites under force.

Your machining skills could come into play here, you could design a four way with center hub to fit the shaft.

The hub shape would be a 'skin' the looked correct but carried no real loads.

That was my approach only I was thinking about printing something in nylon instead of machining an aluminum part.

I do not have a lathe, but wish I did.

Using a combo of nylon print and fine machine screws, I might still give it a go one day.

The other issue would be the total mass of the hub, but it is close to the center of motion, hey I am not an engineer and cannot play one here.

Best, LB

[jetfool]

Elbee,

These cuffs are for the Curtiss Symmetrical prop. It looks a lot like the Hamilton prop so the VS3 FMS Corsair prop represents this the best. Dave sent me a cuff he developed but it didn't have a solid fitting inner filler to conform to the prop. The HS kids are working to make a 2piece cuff that can be glued to the base of the prop. I am making the alum spinner hub, also the HS kids are working on a 3d spinner hub. What we haven't approached yet is a Curtiss propellor hub for the prop blades. It is different than the Hamilton hub. I'm waiting to see how the HS kids get along with these designs and 11 STL printing B-26 parts that they are doing. I don't want to wear my welcome out, but their teacher thought it would be a good project for the class and I should hear something in the next week how they are doing. Plan to show the class later this spring the results they have made and printed for the Corsair, P-47 and B-26.
Do you feel a 3d printed hub would be strong enough to withstand the stress of a spinning propellor. It's a concern to me that it doesn't cause an accident to someone. Hesitant to have a HS class be put in that position.

Best Regards, Rex

[Elbee]

Is this for the Curtis Propeller or the Hamilton Standard Propeller? If I can assist, please let me know.

[jetfool]

Thank you Elbee. A labor of love but I'm thinking the alum. might be a little heavy. I have the HS class re-designing Davegee's 3-d prop hub, he had it done from someone else and the profile is off. If the high school kids do a good job, it will weigh a lot less and we will have a correct STL to print. Enjoying your B-25 up-dates. Ain't this a great Hobby!

Best Regards, Rex

[Elbee]

After an afternoon of filing, turning, filing I have the basic shape.

Truly beautiful work from a master craftsman. Bravo Zulu, Sir. Best, LB

[jetfool]

After an afternoon of filing, turning, filing I have the basic shape. Will scale up my 3-view and make a template to use as a guide for final shaping. Started with a blank weight of 890 oz. Now down to 420 oz. Hope to lighten it more.

Best Regards, Rex

[jetfool]

Started to make an alum. spinner hub today. I have drilled lightening holes and threaded the hub for the VS3 FMS Corsair prop. Threads are m10x1.5mm. As I don't have an attachment for taper turning, I'll turn some metal then a lot of file work. Hopefully this all works out and doesn't weigh a lot.
The High School industrial class are designing a cuff to fit around the prop to resemble the Curtiss prop.

Rex

[jetfool]

For those wanting a Bubbletop. A guy on the other forum has modified his FL P-47. Something to think about

Best Regards, Rex

[jetfool]

Grossman56,
Yeah, those little details bring it to life.
Today was one of those days, sittin, thinkin, not much getting done. I did get the cockpit side panels finished and decided to do a little test with a dirty wash on the underside of the right ele./stab. I wiped on a lite wash of dirty paint and wiped it off till I could barely see it. I figure these planes had some dirt, mud etc. from daily use. Take a close look and let me know if it is too much or not enough. The left elev./stab has not been touched. I can see a used looking plane over a pristine one.

Best Regards, Rex

[Grossman56]

Lookin' mighty fine Rex, the little details really make it don't they?

Grossman56
(Dangerous Dan)

[jetfool]

I finished the brake lines and assembled the landing gear covers. Looking better all the time.

Rex

[jetfool]

Thanks, Dangerous. I worked on my hydraulic brake lines on the P-47 (non-functional) today. It's starting to come back together and look like a plane again.
I will look at your info tonight. I need to get the correct paint for the crankcase on the engine. I should visit the LHS, 30 mi. away, they carry all kinds of paint for the plastic modelers. Need paint for my 1/16 Rc Tiger1 tank too.
Your picture is just what I need to make the spinner, and the cuffs should help the HS kids see what Dave and I are hoping for.

Best Regards, Rex

[Grossman56]

While starting on the engine detailing I noyiced I sprayed the chin scoop white. In looking at pictures they don't show this being painted. I haven't been able to find a straight on picture showing what color. If not painted, was it just aluminum color?
I am using engine grey for the engine crankcase, but it looks darker than my pictures. It is a blue-ish color but dark. Any ideas?
Rex

I just looked through my book, "The Mighty Eighth", and there isn't really a good head on pic there. On the cover on my copy of "Thunderbolt, It looks as if its black, but that's an artist's depiction.

Here's a page worth checking out!

https://www.google.com/search?q=boeing+museum+of+flight+P+47&sca_esv=e5a9fbe4d01470dc&rlz=1C1PRFI_enUS779US779&udm=2&biw=1360&bih=607&sxsrf=AHTn8zpgcpbB-wTDeGXstrKhdJD5unmacw%3A1738102874316&ei=WliZZ7eCE6TN0PEPha_VgQU&ved=0ahUKEwi3l6DjuZmLAxWkJjQIHYVXNVAQ4dUDCBI&uact=5&oq=boeing+museum+of+flight+P+47&gs_lp=EgNpbWciHGJvZWluZyBtdXNldW0gb2YgZmxpZ2h0I***NDdI7MgBUPULWPS-AXAEeACQAQCYAY0BoAGkMKoBBDAuNTS4AQPIAQD4AQGYAh6gAqIZqAIKwgIKEAAYgAQYQxiKBcICCxAAGIAEGLEDGIMBwgIIEAAYgAQYsQPCAgcQIxgnGOoCwgIEECMYJ8ICEBAAGIAEGLEDGEMYgwEYigXCAg0QABiABBixAxhDGIoFwgIFEAAYgATCAgQQABgDmAMJiAYBkgcEMy4yN6AHrekB&sclient=img#vhid=nlo9_n4PyG8UxM&vssid=mosaic

Has pics like this:



Grossman56
(Dangerous Dan)

[jetfool]

Well, the last few days I have started doing some Honey-Do's again, Never Ending! Today after getting supplies to make a Curtiss Electric spinner and taking some 3d STL's to the local High School 3d class I decided to make the retraction strut on the landing gear. Some 3/32 alum. tubing, a broken control link, 1/16" music wire, 20 ga stranded wire and a hole drilled in the landing gear mount I came up with a reasonable retracting strut. As the gear retract the music wire slides in the alum. tube. The stranded wire is glued in the bottom of the alum tube and allows the retracting strut to fold with the gear. The landing gear cover closes as per the original. A few hours of work but a lot of thinking in my sleep to do this.





Next up, landing light bulb, lens and get ready to apply Callie's Graphics which arrive Friday and on to detailing.

Best Regards, Rex

[jetfool]

While starting on the engine detailing I noyiced I sprayed the chin scoop white. In looking at pictures they don't show this being painted. I haven't been able to find a straight on picture showing what color. If not painted, was it just aluminum color?
I am using engine grey for the engine crankcase, but it looks darker than my pictures. It is a blue-ish color but dark. Any ideas?
Rex

[Grossman56]

It works well Rex, I took this picture:

And used, I think, the 8x12 setting on the printer and it came out great. Cut what looked like a donut of cylinders and canted the picture slightly so the cylinders would show between the open areas and viola!:

Thanks Dave!

Grossman56
(Dangerous Dan)

[davegee]

Sounds good, Rex. I have that book, I think. I recommend using taking photos of a cylinder on your plastic nose cowl, shrink it down on a printer, cut them out and glue them in between the other "real" cylinders. If done right, it looks pretty realistic and you can even run spark plug wires to those paper cylinders too, for added realsim. The crankcase on the plastic cowl should be that darker blue-grey gloss as you see in the pics. Follow them, and you'll have a very realistic, engaging "false" R2800 engine in front of your electric motor. I have done this for 15-20 years and never had any cooling issues where the paper goes in between some of those gaps. There is still room for the ram air to get into the engine bay and the rest of the fuse with available hole/openings in the false motor holes.

Have fun!

Davegee

[jetfool]

Well i think all the spray painting is finished. While waiting for Callie Graphics to arrive I keep pushing forward with other parts that need finishing. I have some pretty good pictures of the engine so tomorrow I will start detailing.
Rex

[davegee]

Davegee,
Your pictures are just what the DR. ordered. These will add realism to the plane. I need to add the gun cartridge exit holes to underside of the wing. Did you deepen them?

Best Regards, Rex

Hi Rex: no, for these foamies I just cut scale black rectangles and glued them in place.

Davegee

[jetfool]

Davegee,
Your pictures are just what the DR. ordered. These will add realism to the plane. I need to add the gun cartridge exit holes to underside of the wing. Did you deepen them?

Best Regards, Rex