Micro annular cutter. By Stefan Gotteswinter. 42:15 video:
https://www.youtube.com/watch?v=x6LUpi6W3YA
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Micro annular cutter. By Stefan Gotteswinter. 42:15 video:
https://www.youtube.com/watch?v=x6LUpi6W3YA
Made a set of tuning pegs that very same way, in brass, a bit larger peg. 400 fit in a disappointing small box of 3+ days work.
Best way to observe heat color transitions is lowering the level of light intensity. Tempering reveals better when the surface is polished, and not intense lighting.
Quote:
Originally Posted by Toolmaker51
this is not something I have experience with, just yet, but I've read that cutting plastics and softer metals, like brass, you want a less acute angle on your cutter. "Dubbing" is what they call it when you do it to a drill, IIRC. Can you confirm or deny?
On the subject of tempering, early 1903 Springfield rifle actions were tempered by eye, and there was a potential problem with them shattering due to inconsistent tempering due to changes in the lighting in the armory from day to day and with varying weather. The very first Springfield I ever owned was one of those. Not that there were many that did shatter, but it's, shall we say disconcerting?, to have that happen when the thing is held near your face... Mine wound up as a wall-hanger on my dad's wall, and I eventually got another that wasn't in the early serial number range. The armory folks got pyrometers for their tempering ovens so they could avoid the problem. This is mentioned in Hatcher's Notebook, if anyone else is interested.
Bill
All of it, interested in all of it. I channeled up the Maj. Gen'l just days ago in a discussion (one side ranting) regarding flat earth phenomena. Orrery's, ballistics, space flight, navigation, plain old physics, astronomy, sunrise & set, the works.Quote:
Originally Posted by WmRMeyers
Typically, the only evidence they produce are photo's; minus working knowledge regarding optics.
Good times.
I participated in Pacific Fleet Matches at Camp Pendleton. Garands, M1-A, AR patterns abound. A few 1903 A3, but not in 1000 yard matches vs other service rifles, too advantageous. There's never been a superior bolt action service rifle. It's thought of, in comparison to the Mauser (ideal hunting rifle), Enfield (ideal battle rifle) the ideal target rifle. Tough combination when majority of troops were trained as riflemen/ marksmen, not hunters or just infantry. Much of it hangs on the original sighting, evolved from the tangent style of the Krag.
A 1/2'' (minute) small aperture on a Garand isn't so bad either. My Garand remains as issued, MI-A wears NM, installed by none other than armorers from NSWC-Crane. They travel in a mobile armorers lab. Now, that would be a job!
Yeah.
All of it, interested in all of it.
Oh BTW, not aware of a term applied to removing a bit of drill helix, instead one or another description of the process, something parallel to "just stone the lips". That business with brass occurred lots. I'd usually get a pilot through, and step the final bit with the depth stop or knee. The real problem lies in lash of rack and pinion quills, far less when screw or gear train fed.
I've heard several old timers refer to "dubbing" drills. This reference...
https://www.ctemag.com/sites/www.cte...8-Geometry.pdf
at the bottom of the second page has this quote...
Another feature that can be ground
on a drill is a dub. Dubbing is the act of
placing a flat grind across the flute faces
from the outermost diameter to the
chisel edge. This alters the rake angle of
the tool to 0° or just slightly positive.
Dubbing strengthens the cutting edge
but increases the plowing effect. A dub
can be useful in materials that tend to
“grab” the drill or when additional
strength is needed to prevent chipping.
I've also heard the process of touching the shoulders of a kneeling person with a sword in order to confer a knighthood referred to as "dubbing".