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C00002 00002		NOTES FOR ASSEMBLY OF STANFORD ARM KIT COMPONENTS
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	NOTES FOR ASSEMBLY OF STANFORD ARM KIT COMPONENTS
		by VICTOR SCHEINMAN- VICARM
			MARCH 20, 1975

	The Stanford arm kit of components consists  of all the parts
mentioned   in  the  purchased   parts  list  plus   all  the  custom
manufactured parts denoted  with an "S"  in the  set of arm  drawings
supplied  with  the kit.    In  addition,  all modifications  to  the
purchased parts, if necessary, are completed by Vicarm.  

	The kit  is shipped in three or four separate shipments.  The
first  shipment is  the  bearing  shipment.   Not  all  bearings  are
shipped, as some  are used in the subassemblies  supplied later.  The
bearing shipment should allow the user to assemble most of the  basic
arm  components.   Joints  1,2,3,4,5,  and  6 can  all  be  connected
together for fitting purposes.  

	Notes on the installation of bearings.  

Joint 1: First slip the clamp ring (9-9a) onto the drive tube(9-5)
.    (The drive  tube  should  have the  screw  access  holes already
drilled, as noted in the latest drawing set.  Then the  upper bearing
- KA-040-XP0 is  slipped on the drive tube.   Then the retaining ring
(9-  ) is slipped on.   Using machinists  clamps, clamp the retaining
ring-bearing -drive tube  flange together tightly  and dowel pin  the
retaining ring in place. Mark  the ring and tube so it can be removed
and replaced in the  same spot in  the future.   The lower bearing  (
KB-040-XP0 )is tipped  sideways and dropped  into the main tube.   It
should  be a light  slip fit  on both the  main column and  the drive
tube.  Seat the bearing at the bottom of its seating diameter.   Then
drop the main tube  into the column.  The clamp  ring is screwed down
with socket  head screws inserted thru the access holes in the top of
the drive  tube.   If  the arm  is going  to be  used  in an  upright
position, it is probably  not necessary to retain bottom bearing, but
this can easily be done by slipping on another retaining fore putting
on the  bottom bearing  and dowel  pinning it  in place.   The  exact
position can  be determined by squashing the ring  a bit so it sticks
the the drive tube. Then when  the tube is inserted, the earing  will
push the  retaining ring up to  the right point.   carefully removing
the  tube will keep  the ring  at the t  point until it  can be dowel
pinned in place.   Some bearing  preload can be  added by putting  an
O-ring  between the retaining  ring and  the bearing with  about .015
O-riing squash to act as a spring.  Don't put anyy more preload than
.015 with this method.  If in doubt- just forget the O-ring and leave
at .005 clearance between retainer and bearing.   The bearings are of
the type which quires little or no preload anyhow. 

	The second  joint is assembled in a  similar manner.  In this
case, the rear  (motor end)  bearing acts  as a pilot  for the  motor
mount plate.  

	Joint #3-
	The  square tube  boom rides  on 16  rollers.   Only about  6
rollers  are actually needed to guide the  tube, so dont worry if all
dont contact at the same time. The rollers are made up from the 34KDD
bearings  supplied  and  phenolic rings.    Epoxy  the  rings to  the
bearings with two bands of cement -  one one each side.  The  rollers
are sttached to the shafts with Locktite  adhesive.  Use Locktite #35
or #40  adhesive (available from bearing  supply firms),and place one
of the  roller clamps  in the  center.   The spacing  of the  rollers
should be about 2.30 outside to outside.  This will insure that there
is  no interference with  other rollers.   The boom  should fit tight
enough so that  it springs the rollers  out a bit.   If it fits  very
loosly, shimm the roller blocks with shim stock.  

Joint 4,  5 and 6.   The installation  of the main  shaft bearings is
self explainatory.   It is  advisable to  make some  simple plugs  to
install and remove  these bearings, as acrewdriver blades  and knives
are not  good for the bearings or the parts.   DO NOT hammer bearings
into place- press them in, on a drill press if an arbor press  is not
available.  Also, plan on having tooling for removal before ining the
bearing. 

Installation of the small shaft bearings on the R6 joint and Hand wil
be discussed later int he section on main assembly.  For the present,
its good enough to check that all the main drive shafts fit together,
and the arm shructure assembles properly.  



Shipment #2. 

	This  consists  of  most  of  the  purchased  components  and
critical assemblies.    The only  mechanical parts  not included  are
those with an electrical function.  (Such as the drive gear on the #6
joint, and the #3 encoder or pot.]

	You will probably want to assemble joint #1 first.   Test fit
the motor  assembly in the  column.  It should  drop into place.   It
should also  slip into the drive tube.  You will note that because of
the coaxial nature  of the assembly, it  is not possible to  just fit
everything together  and bolt  it into place  later.  You  must screw
things together while assembling arm.  
	The addition of an access hole in the side of the main column
allows for easier assembly  because with it, you can  assemble the #1
joint  by dropping  the motor  assembly in place  and putting  in the
screws.  Then put  in the bottom bearing.   Now slide the drive  tube
assembly with  the upper bearing  and clamp ring already  installed .
The  access hole allows you  to screw in its bolt  circle.  There are
access holes in the top plate of the drive tube to allow you to screw
down the clamp ring.  
	Joint #2 is assembled in  a manner similar to joint #1.  Note
that the rear (motor end) bearing serves to center the motor mounting
plate also.  The #2 motor assembly is not complete as the motor mount
plate is not part of the kit.  You must first mount this plate to the
motor, and then bolt on the harmonic drive.  It may be  easier to get
the harmonic  drive screws  in place  if you  remove the  three small
phillips head  screws shich hold on the diaphram assembly.  The motor
drive system has a slip  clutch on the hollow drive shaft.   The slip
torque has  been preset, so dont  adjust the two locking  nuts on the
drive shaft.  The shaft thru the  center of the motor comes from  the
encoder.   it is connected  to the output  thru the thin  diaphram to
allow  for som axial play  during assembly and due  to motor heating.
When  assembling the  unit,  make  sure  that  the  diaphram  is  not
bottomed, but  has free  travel in both  directions when  the encoder
shaft  set screw  is  tightened.   Also remember  that to  remove the
encoder or get access to  the motor brake( under the black  motor end
bell at the encoder end), you must first loosen the encoder shaft set
screw.  Only after doing  this is it safe  to remove the brake  cover
screws and slip off the encoder and brake assembly. 

	Joint #3 motor  is first mounted  on the square  tube (9-20).
The front  motor bearing acts as the centering  device too.  Now wire
up the  motor, brake  and  tach and  slide the  motor into  the  head
assembly.  If it doesnt go all the way in, the encoder shaft on joint
#2  sticks out too  far, so cut  it off flush with  the diaphram hub.
The mounting scre are socket  head and the use of a stubby  wrench is
recommended for  easily working in the confined  inside of the square
tube.