This is the before picture with the spindle pulley removed.
Using the 45 tooth gear a mark is made in the approximate new location.
It does not matter what size gear is used here.
The tumbler gear is just a "filler" gear
and will not affect the threading ratios in the
reverse position. I choose the 45 tooth
gear for it's size and the fact it is used for
only one metric thread.
And yes I have cut LH threads without any problems
Here I chose to cut out the bracket shown above. This will allow 3/8"
thick steel plate to be used for
the gear carrier plate.
The plate is held on with 2 allen head screws.
The plate was removed and cut with a jigsaw / metal cutting blade. The
plate cuts pretty easily and
could be done by hand with a hacksaw.
Here I am centering the 45 tooth gear and placing a mark to get an
idea of where
the gear will be placed. I would suggest rather than centering the
45 tooth gear
between the spindle gear and lower gear, to move the 45 tooth gear
a little
below center and marking. This will make sure that there is plenty
of room
for a neutral when building a forward / neutral / reverse latching
mech.