The next day all the clamps were removed giving me seven
blanks for the leveling wheels. They
were momentarily set aside while the rest of the cut pieces were glued and
clamped up just like the first set. In
the end I had fourteen blanks, the two extras are for backups if there is a
problem. I also made a design
change. The left drawing below is the
original design and it shows a T-nut used to provide the ¼”-20 threads in the wheel
to enable it to run up and down the adjusting bolt. The revised plan on the right is to use a
regular ¼”-20 nut set into the wheel and locked in place using epoxy.
Taking the blanks and turning them into finished parts
requires a series of seven steps. The
first one is to find the center of the blank.
That’s done using the dial caliper set at half the total width and
striking a line from adjacent sides.
With that done a compass is used to draw a circle just a bit larger than
the finished size. Both of those are
done in the left blank. The center blank
has a flat bottom hole ¼” deep for the nut to set into. The far-right blank has had a 9/64” through
clearance hole for the bolt to pass through added.
Below the top photo goes through the last four steps starting
on the left where the blank has been rough cut to a circle on the bandsaw. That’s followed by epoxying the nut into
place being careful to make sure it’s square with the blank and the spaces
between nut’s flats and the wood are filled.
Once the epoxy has cured the surface can be sanded to remove any excess,
third from left. At the far right is the
finished wheel. The bottom photo is of
the blank mounted on a fixture in the lathe so the wheel can be turned
round. After all 14 are done they are
set aside until needed when I will pick the best 12.
Now it’s time to go back and do more work on the sliding
blocks. Between the time I started on
this project and now I decided to change these parts a little. The top drawing shows the original sliding
blocks in the leveling assembly. Front
and back views of the originals are also shown at the top of the lower
drawing. The revised sliding blocks are
shown at the bottom of the lower drawing.
Originally there was a T-nut on the outside face of the sliding block
that a thumb screw ran into and when tightened put pressure on the base locking
the leveling assembly in place. With the
T-nut in that location when the thumb screw is tightened the applied force
would try and push the T-nut out of the sliding block. I didn’t like that so decided to move it to
the inside face so the pressure would push the T-nut tighter into the sliding
block. There was just one problem, a
T-nut will not fit in the space available at that location. The solution is to use a ¼”-20 nut epoxied in
place just like what was done for the wheels.
The only other change was to lower the hole so the nut could be centered
in the available space.
The work starts by drilling the hole so the nut can be
recessed flush into the sliding block.
There is not a lot of space on either side where it goes so once the
center had been accurately located the center finder is used to center the part in the drill press at the correct position. A
stop block and fence are used so all the parts can be made the same. The left photo shows the drill press setup
with the stop block clamped in place.
The right photo is a closer view.
With everything set the center finder is removed, a
Fostner bit chucked up, a depth stop set and the partial depth hole
drilled. That’s all been done in the
left photo. From here it’s a simple
matter of clamping the next piece in place, drilling and repeating until all of
the six blocks needing the holes are done.
The right photo has the Fostner bit replaced with the one needed to
drill the through hole for the thumb screw.
Since neither the fence or the stop block were changed the hole gets
drilled perfectly centered in the first one. 
With both holes drilled the nuts could be glued in
place. I used a slow curing (18-24 hour)
2-part epoxy. That way there is plenty
of time to make sure they are in the right place and the space between the nut
and the countersunk hole’s edge gets completely filled. While the gap did get filled the process is a
little messy. The next day it’s time to
do some cleanup. Using three different
sanding blocks each loaded with a different grit of sandpaper it didn’t take
long to clean the mess up. The two
photos on the right show before cleanup and after. As the nuts are going to be buried out of
sight, they didn’t need to be perfectly clean nor was it required for the epoxy
to be kept out of the oak’s pores. If it
had been critical to keep the mess to a minimum, I would have masked off the
wood outside the application area and cleaned up the nuts themselves.
Next is to put together the slider blocks and the base
plates shown in the drawing below. It is
important to make sure the base plate and slider block is aligned
correctly. If they are out of alignment
then they won’t slide easily on the base plate.
To make sure of good alignment they will be put together
with screws first. I can take my time
with the positioning before gluing and not have to worry about the parts
sliding out of alignment when clamping.
After marking out the screws locations their pilot holes get made on the
drill press. Only one setup is needed as
all the holes are at the same place in each corner. The left photo is the setup with the first
hole drilled. The right photo has the
piece flipped so the face is now down and it’s ready for the second hole to be
drilled. The holes on the other end just
require the piece be flipped end-for-end.
Next Up – Assembling Base Plate & Sliding Block – Thumb Screw Problem
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