Sputnik Man asks:
"I
found your site surfing trying to find a way to straighten a 6" diameter brass sphere with about .030 wall
thickness from an old sputnik light. The sphere has a circular opening about 3" in diameter. I have no
clue how this thing was manufactured, much less how to get it smooth again."
Tin Man responds:
Sputnik light? Are the Russians now selling off the bits from their space program?
Sputnik man: "nothing as exotic as that. sputnik spawned many consumer items in the late 50s and early 60s
that looked suspiciously like the satellite. This is a hanging lamp, a 6" sphere that has 24 arms
radiating outward with bulbs on the end of each arm. Over the years force on the arms bent the sphere
out of shape. I'm trying to restore it. I have it functionally back in shape, but you can see the hammer
marks. I used a PVC pipe cap filled with sand for a dolly, because that's all I could find close to a 6"
radius that would fit inside. It would be nice if I could get it smooth again. Any ideas?"
TM:
Roughed out? Now the planishing work begins, (smoothing by light hammering). Choice of either slapper or
spoon depend on material Temper Alloy and Thickness. Dolly must match contour. Slapper or spoon must be
the right weight; not too heavy, or stretching occurs, but just heavy enough to smooth easily.
The slapper covers several weights, from about 6oz. to about 12oz. the spoon is the finesse tool, and has a
minimum striking weight of from just an ounce up to about 5 oz., so you can see the 2 tools cover quite
a range of striking weights. In use, they may be used to strike directly, spanning two high spots and
bringing up the low in between by inertia (booklet:
Using The Slapper
), or simply to knock down a high, leaving fewest marks of any metal tool.
Otherwise, they may be struck with a hammer, spreading the force over a larger area, and leaving few or no
marks.
The video,
Basic Damage Repair on The Aluminum Body
covers this, and the application is the same on brass.
Also, the video,
Workshop on Alum. Body Restoration
shows planishing and metal finishing with a body file, (smoothing by removing metal)
.
END OF MISCELLANEOUS FAQS
|