250 Years Trying to Divide 360° Perfectly

Comments · 24

• OG

  @OGMann · 2 hours ago

  There's a difference between the ability to divide a circle and the precision of physical devices.

  1

• RO

  @ronaldsmith-f9s · 1 day ago

  As a layman I am totally in awe of the accuracy that was available in 1775.

  4

• MB

  @Mbartel500 · 16 minutes ago

  And this boys and girls is why there are “manufacturing tolerances” in virtually every machine operation. “Perfectly precise” is not the same as “precisely perfect”.

• SH

  @shopshop144 · 23 hours ago

  One of the better AI videos.  Interesting to note when American businesses stopped being mentioned, but Swiss and German companies seemed to continue to make advancements.  The space race divided the skilled work force into brains who generally didn't build anything and the skilled trained worker who generally pushed to truly understand what they were doing, just get the job done.

  4

• ME

  @melgross · 1 day ago (edited)

  My record turntable has a direct drive motor which is an implementation of the direct torque motors they’re talking about here. Speed accuracy is 0.0005% or better. Wow and flutter is under 0.05%. Speed can be easily adjusted. The same type of motor, different usage. I use three phase motors on my machine tools, controlled by variable frequency converters. These have direct control, have torque control fo slow speeds, can be speed adjusted over a wide range and can be “locked” at difference angles. Well made ball screws can eliminate backlash and has very accurate thread spacing as it’s a screw that can be ground extremely accurately. Very little friction and it’s rolling motion as any ball or roller bearing. It’s all very interesting.<br><br>This was a pretty good video, though it missed a few points.

  2

• AI

  @aikonlatigid · 15 hours ago

  I usually use motorcycle chain circulating conical wheel, just adjust chain number, works perfectly

• TR

  @trevorallen3212 · 23 hours ago

  As person who wanted to avoid circlar reasoning thank god for principle of self correction.

• JO

  @josephgrillo9717 · 16 hours ago

  WOW! Things have progressed since Jesse Ramsden 1775 to Mr. Kelly&apos;s machine shop class at Brooklyn Technical High School 1964! This video is great to watch but depressing as the end notes the lack of USA involvement in machine shop R &amp; D.

• OL

  @oleyorkie · 1 day ago

  Absolutely fascinating video. Back in the 1960s I worked on worm drive dividing engines producing circles for surveying instruments in England. Accuracies of 1-2 arc seconds were routinely achieved. By the mid 1970s the factory had closed and a great deal of knowledge and skill was lost.

  6

• DP

  @dpasek1 · 22 hours ago

  Did they use sine bars to lay out the master indexing plates?

• TR

  @TriumphT100T · 21 hours ago

  I normally consider AI videos as slop, but this is actually very good.

• 59

  @59jm24 · 5 hours ago

  I am able to locate bolt circle holes with the aid of a digital readout on the mill... accuracy is another question, I have no real way to check other than if the part fits.