Tracker Bar Construction
Here is another alternative way of constructing the tracker bar, similar
to Walt Lysack's method:
Instead of the fiddly cardboard construction, a piece of close-grained 5/8"
hardwood 5 5/8" long, by 1" wide is used. This is drilled using a pillar
drill with a tiltable table to create the airways from the tracker bar top
to the tracker bar base plate (my pillar drill is the cheapest Clarke DIY
from Machine Mart). It may be possible with a battery drill by hand
if you have a good eye for angles!
1. Make the tracker bar top and drill the holes according to the plans.
2. Trace to hole positions onto the hardwood block.
3. Set the pillar drill table to 15 degrees from horizontal and drill 10
ALTERNATE holes through the block using a 7mm twist bit for the 3 bass pipes
& 4.5mm TWIST bits for the 17 other pipes ( I clamped a piece of wood
along the drill table to act as a guide so the holes are all in line).
4. Turn the block around length-ways and drill the remaining 10 holes of
the correct size.
5. Place a 5 5/8" by 1" piece of thin cardboard (cereal packet) over the
bottom of the block and press your finger hard over the two lines of holes,
you will get an impression of the hole location on the other side, this is
then placed centrally on the top of the 1/4 ply tracker base plate and using
a sharp implement (I used the point of a pair of compasses) transfer the
centre of the hole positions through the card board onto the ply.
6. Drill the fifteen 1/4" & five 5/16" holes through the base for the
7. Carefully glue the three parts together checking all the holes line up
Here is a photo of the parts, including a diagram of the tracker block.