DEC H960 stabiliser feet. Have some questions.
    Noel Chiappa 
    jnc at mercury.lcs.mit.edu
       
    Mon Jan  8 07:25:12 CST 2018
    
    
  
    > From: Steven Malikoff
    > That's the first actual photo I've seen of the foot, and I see what you
    > mean.
Oh, I can take more, then; let me know what you need.
    > Let's regard the inner vertical surface where it mates to the rack as
    > the normal surface.
Right; that's our reference plane.
    > If you have a length of something straight .. clamp it with a .. clamp
    > to that inner surface
Umm, not possible. There are two diagonal (in the horizontal plane) ribs
coming off that surface, so there's no way to clamp anything vertical to
it. The _front_ (outer) surface, parallel to the reference plane, I could get
to (and the clamp is a good idea). Here's what I wound up with:
  http://ana-3.lcs.mit.edu/~jnc/tech/jpg/StabilizerMeasurement.jpg
(Yes, yes, I know, tha assumes the back face of the square is parallel to the
front; it is, pretty much - I checked with a vernier calipers.)
So the vertical distance from the horizontal plane at the bottom of the
stabilizer, at its tip, to the bottom of the 'outer surface' (as above), is
17/32". The distance from the plane of the 'outer surface' to the end of the
stabilizer is 7-9/16". The distance between the reference plane and the 'outer
surface' is 7.14mm (one thing I _could_ get a vernier calipers on :-).
				
Also, it turns out the right-hand vertical face of the stabilizer is _not_
perpendicular to the reference plane! The foot angles in slightly. The outer
vertical surface is a plane along its entire length, so it's hard to notice
unless you put a square on it directly:
  http://ana-3.lcs.mit.edu/~jnc/tech/jpg/StabilizerAngled.jpg
(Sorry about the lens distortion; wanted to show that the square was along
the reference plane.)
I couldn't get anything clamped on to make the measurement, but the tip of
the stabilizer is about 1/2" (to a /32nd, or so) in from a vertical plane
perpendicular to the reference plane, and situated at the right-most location
on the foot (i.e. along the edge of the square, in that photo).
    > A pencil rubbing on paper, or paper creasing slong eges then drawn over
    > with a ruler can also help to get angled surfaces.
Sorry, couldn't figure that out?
    > Another thing, CAD can make good use of non-perpendicular measurements.
    > So if you're able to measure something across a diagonal or at some odd
    > angle, then please do so. It can be used to triangulate and improve
    > other taken measurements, like a point cloud.
What other measurements should I take?
One easy/obvious one is from the right-hand outer bottom corner of the
stabilizer to the left-hand bottom corner of the reference plane: that's
8-9/32". (A lot of these corners are rounded, so exact measurements are a
matter of choice....) The top inner corner of the right-hand face is 9-11/32"
from the bottom outer corner of that face (same corner as above).
	Noel
    
    
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