anyone built the new Spirit of St. Louis

Wanted to know how the decals used for the burnished cowling worked out.
Thanks
Hub
Reply to
Hub & Diane Plott III
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There is a nice article here:
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Reply to
Greg Heilers
ISTR an article a LONG time ago about someone building an NYP model, don't remember scale or media or anything, but their solution to the swirls was a pencil eraser in a drill after the cowl was painted.
Reply to
frank
Funny.....that has always been my first suggestion (actually, a sharpened eraser in a rotary draftsman's electrical eraser)....but I figured the idea was too "gonzo" to mention.
:o)
Reply to
Greg Heilers
...and I'd sheet the area with foil.
Reply to
Rufus
That's close. I used a portion of a mechanical pencil eraser (Pentel I think) that I CA'd onto the end of a piece of sprue about 1/8" dia. I chucked the piece of sprue into a Dremel tool and turned the eraser down to the sprue diameter by passing it over a coarse sanding stick. The resulting tool is an eraser about 1/8" diameter. If you are careful you can spot-face a decent pattern on a foil covered NYP cowling. I kept the working surface of the eraser flat. No abrasive is required. The pattern that results in the foil is delicate so care must be taken when brushing off the resulting Al oxide (?) residue.
MB
Reply to
Milton Bell
Not too "gonzo" at all. Many years ago (more than I care to admit to) I saw that Revell 1/28 scale Sopwith Camel at an IPMS regional and the gent who built it had done the cowling and side panels as machine turned aluminum. That was the method he used, a draftsmen's electrical eraser with a pointed insert. Looked terrific.
Bill Shuey
Reply to
William H. Shuey
My thanks to all of you.
Reply to
Hub & Diane Plott III
This depends a LOT on scale. If one is doing the big Guillow kit, a pencil eraser may make sense. But that is too large for a 1/72 or 1/48 model. It would be a bear to come up with something appropriate in that scale
Reply to
Don Stauffer
Not really. The basic eraser is 1/4" in diameter, but you can use an exacto to sharpen it to a point and get very small swirls. As an aside, I earned my living as a draftsmen and designer for many years and made the acquaintance of the electric eraser professionally. When I first saw one being used my reaction was "How lazy can you get"? But once you tried on it was a revelation what control it gave you. I went out and bought one for use at home. Then they invented computer drafting--- :-)
Bill Shuey
Reply to
William H. Shuey
Not really. The basic eraser is 1/4" in diameter, but you can use an exacto to sharpen it to a point and get very small swirls. As an aside, I earned my living as a draftsmen and designer for many years and made the acquaintance of the electric eraser professionally. When I first saw one being used my reaction was "How lazy can you get"? But once you tried on it was a revelation what control it gave you. I went out and bought one for use at home. Then they invented computer drafting--- :-)
Bill Shuey
Reply to
William H. Shuey
"William H. Shuey" wrote in news: snipped-for-privacy@starpower.net:
Any body know why they "whirled" the original sheet metal on the NYP? Did/does it have any mechanical reasons, or just looked good?
Cheers,
Dennis
Reply to
me-me
This used to be a sign of craftsmanship. Originally it was "hand turned". Then they started doing it with machines, and the description was "engine turned".
Originally it was done with a chisel, rotated on a flat machined surface. I can only guess at this, but it would have removed milling machine marks and replaced them with a more attractive pattern.
It was a way for an apprentice to show that he had progressed to a journeyman (not an official test, but to show off and say, hey, I am one of you guys now).
It used to be (actually, probably still is for a really talented master machinist) that one could hand scrape a surface flatter than one could machine it. Hand scraping was a key skill. The hand turning helped demonstrate you had acquired such skills.
So hand turning became a decorative art that was far more easily duplicated with the machine process when that became possible.
Reply to
Don Stauffer
ISTR reading that its purpose was to smooth & hide hammer marks. During a time before presses & dies, concave or convex surfaces were shaped with ball-pien hammers & such.
Reply to
frank
"frank" wrote in news:1140449754.264413.240090 @g44g2000cwa.googlegroups.com:
I asked because I have made a copy of an engine cowling for our museum. It was for a WWI fokker and had it had the swirled finish. I used My English wheel to smoothen the thing and used a steel wire brush in an electric drill to get the swirls on. I was rather proud of my self with the finish, but now I know it was originally done with a chisel, I see my method was just cosmetically correct.
Dennis
Reply to
me-me
I was thinking that in the movie "The Spirit of St. Louis", they used a wire brush in a drill press to do the swirls. But, it WAS just a movie.
me-me wrote:
Reply to
frank
This does not apply to machined surfaces where the physical purpose it lubricant retention, it later became decorative.
Reply to
Ron Smith
That makes more sense than any other "theory" I have heard. I had read (somewhere...) that such a surface was an aid, in the "anti-icing arena" (gee...that sounds like a place where Politically-Correct hockey games would be played), but if so....somebody please explain the physics...
Reply to
Greg Heilers
I don't think it had anything to do with lubrication retention on the Spirit either. :)
Reply to
frank
Just chiming in here but.. The swirl may have been used to break up the lamina flow of the air over the skin of the plane. A fluid moving along the surface would tend to "stick": to the skin if the skin is slick/smooth. To increase speed or duration, they may have provided a slightly non-smooth surface which would break up the lamina flow. They did the same thing a few years ago with the Americas cup racers. The bonded a mylar surface to the bottom that had micro ripples in it to "loosen" the hull from the water. R. Wink
Reply to
R. Wink

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