Re: [CAD_CAM_EDM_DRO] Positioning

     Jon, could explain how you came about the .0318 drum diameter?  I know
the force is low, but how did you arrive at this diameter.

it is .0318 RADIUS, not diameter.  If you had a drum that pulls a
string 0.200" every revolution, then you have Pi * D = .200, so
D = .200/Pi or .063", so the radius is half that or .0318"
The ballscrew with a 5 TPI lead or .200" per rev is a rolled-up
version of this, the motion is equivalent.  This shortcut is a LOT
easier than figuring the tangent angle to the face of the thread.
it doesn't work for Acme screws as the friction of the screw/nut
are quite significant.  But, I am pretty sure this way of calculating
it is pretty close for a ballscrew.  (It doesn't take friction into
account, but that is small of the ballscrew.)

I've been using this shortcut for years, I'm pretty sure it is
OK, but if somebody can find an error there, I'd be glad to
be corrected.

P.S.  Jon how is your sons doing?

My oldest daughter has a cosmetology license and does hair stuff.
#2 daughter just graduated with a teaching degree and is interviewing with
school districts.
#3 daughter has one more year of college.
Oldest son is in college, just helping him buy his first car.
#2 son just got back from a high school trip to the UK.
#3 son in high school.
All doing well, thanks for asking!  Maybe we'll have some more
time to do stuff now that school is out.

So, how are you doing, Bill?  Haven't heard anything about your
big lathe project in a while.  Sad the CNC Workshop has dissolved,
I enjoyed the meetings.

Jon