Here’s a guide that details the
steps I used for setup and
1. Place a long 1/4 inch diameter x
7 inch long drill into the 1/4 inch
A. You can substitute a dowel
or rod, but be sure it’s
perfectly true and straight.
2. Apply power to the fixed mount
lasers and observe the lines
projected onto the table.
3. Set the Z axis to the elevation
where you expect to do most of
your center finding. For each laser,
rotate just the focus ring on the
laser until a fine crisp thin line is
traced onto the machine table.
Initial Axis Alignment
4. FRONT LASER: Once focused, rotate the front laser
module in its holder bracket until the line on the table
precisely traces the Y axis of the machine. When the laser
beam is correctly tracing the Y axis, gently tighten the front
module set screw.
5. SIDE LASER: Once focused, rotate the side laser module
in its holder bracket until the line on the table precisely
traces the X axis of the machine. When the laser beam is
correctly tracing the X axis, gently tighten the side module
Laser to Table Perpendicularity
6. As depicted in Figure 7, observe that each laser line is
traced onto the long drill in the machine. For each axis,
move each laser mount left-right and slightly rotate the
bracket as needed until its laser line is exactly centered
down the whole length of the drill. Gently tighten the
bracket mounting screws, repeatedly checking that drill
center tracing is maintained.
7. Once again, verify that the front and side laser lines
traced onto the long drill are both centered and straight
(Figure 7). Repeat Step 6 as needed.
8. Place a machinist square onto the table accurately
aligned to the X axis of the table. Move the X-Y table
location until both laser’s lines just start to trace both the X
and Y edges of the square (see Figure 8). Make small
tweaks to the laser mounts (Steps 4 and 5) as needed to
achieve this result.
9. While tracing the edges of the machinist square, move
just the Z axis of the machine up and down.
A. If everything is well-aligned, the laser lines on the X-Y table WILL REMAIN STATIONARY as the Z axis is
moved up or down.
10. Clamp a piece of scrap metal onto the X-Y table and
load a small drill bit into your machine. Drill the smallest
start of a hole into the surface of the metal to mark the
true center point on your machine spindle. If everything is
properly aligned, the X-Y laser lines will be dead centered
on the hole you just drilled.
11. You should now be able to move the Z axis up and
down and observe that the laser cross hairs do not move
off center of the drilled mark.
Complete design details for a fixed mount laser
alignment method has been presented. The availability of
small low-cost lasers made this project easy and fun to
construct. This alignment scheme works well for me and
can be readily adapted to any drill press, milling machine, or
Next month, we’ll explore how spindle mounted laser
center finders can be easily designed and fabricated. See
you then! SV
Figure 8. Use a machinist square for laser alignment checks.
SERVO 05/06.2018 67