Blake,
This is turning into a nightmare.
Don't drill the 10 mm holes. I am not sure where they are.

:~0

OK I know that it is a Pain in the Ass!

I used the "point" command in ACAD R12 to place a point according to Tracy's
angle and radii. I then drew a line from the center using the "center" snap
and the "nearest" snap to the point. The line did indeed go through
the point when you zoomed way in on it. I then used the "angle" dimension
to measure the angle of the line and it came out at least one minute off every
time. That is not much at this radius but it is 3 thou (.003) off
in the Y direction.

I also noticed that the 180 degree line was off one minute if you drew
the line from the origin using the ortho function. This perhaps
is the root of the problem in ACAD R12 but I think not.

Yah that is the little error that I picked up when I verified the angles to a set of
vertical/horizontal lines.

Wierd....Are you an old ACAD user (personally it drives me up a wall) because I can
send you a copy of CadKey 7.5 - its a few years old but is capable of some decent
work.

Butch, do you know about this ACAD R12 bug?

I tried converting Tracy's angles, minutes and seconds to decimal
degrees and plotting the points again using the "point" command.
Same results. Apparently there is a serious bug in ACAD R12 or
the floating point calculations in the processor I am using.

I will try this in ACAD R 11 and see what happens.

I would not use those 10 MM hole positions on the drawing as the gospel
truth. Perhaps you can tweek the NC tool G code to Tracy's angles.
In any event I can use Tracy's plate to match drill the 10 MM holes.

I can fiddle with it, let me finish the pockets and then all the drilling will be
done later.

I havnt opened the attached files yet, but is the bolt pattern dimensioned from the
front? (or the back.... ;(

I corrected my mistakes in the angle table for hole number four  and changed
the hole numbering system back to Tracy's hole numbering system.
The dwg, iges and dxf are in the attached zip file.
Paul Lamar

Don't eat too much turkey!
Blake

I calculated the x and y coordinates on one of the holes and it was .006 
off where ACAD "point" command said it should be using Tracy's polar coordinate 
numbers as input. I still think there is bug in both ACAD R11 and R12.

I will convert all of Tracy's polar coordinates to rectangular
coordinates using a calculator and redraw it for the umpteenth time.

I sure hope who ever made Tracy's plates used the polar coordinates
and not the position of the holes on Tracy's drawing. At this point
in time I have no idea exactly where those 10 mm holes are. Oh well I have
Tracy's plate that does indeed fit so I will just match drill it
using a transfer bunch.

BTW Tracy how did you measure the position of the holes on the bell housing
when you made the drawing in the first place.

Paul Lamar
 
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