ididit Retrofit Steering Column: Tri-Five Chevy - Manual (Page 9)

8
How to make a DD Shaft
The shaft of the gearbox will now need to be cut into a DD shaft. This
is a round shaft with flats centered on two sides. An easy way to do this
is to make a paper template. Create your own template by using the
measurements from the diagram below.
Note: Diagram not to scale
.395
.945
1.525
2.075
2.356
1.000”
Starting from an 1/8 from the bottom, wrap the
paper template around the shaft and match the
horizontal arrows together.
Mark the shaft at the 8 vertical arrow points
and draw a line down the length of the shaft,
connecting the marks. This will create the shaded
“D” sections found on the template.
With a grinder or similar tool, grind flat the
shaded “D” sections to match the DD shaft. As
you work, use the coupler as a guide and test fit to
ensure proper fitting.
Another option would be to remove the gearbox
and take it to your local machine shop to be
modified.
To make 3/4 DD shaft
remove .100” from
opposite sides of the shaft
Original Shaft
New DD Shaft