THORLABS Vytran LDC401, User Manual

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LDC401 & LDC401A Automated Cleavers Chapter 8: Maintenance
Rev B, July 19, 2017 Page 23
8.3. Re-Positioning the Cleave Blade
Only a small portion of the Cleave Blade edge is used to scribe the fiber. If this local portion of the edge gets
damaged, the blade can be re-positioned to a new “un-used” section. While the lifetime of a given section of the
blade can be very long (greater than 5,000 cleaves), it is also very easy to damage the blade due to excessive
lateral stresses (stresses perpendicular to the edge of the blade). This can occur if the blade is in contact with the
fiber and the fiber then moves sideways across the edge of the blade. The most common occurrence of this is a
result of the Cleave Tension being set so low that the fiber is unable to be cleaved. In this scenario, the fiber will
slide along the edge of the blade and take a small semi-circular “bite” out of the current section. For small localized
damage such as this, the blade can be re-positioned approximately 9 times.
To re-position the Cleave Blade:
1. Locate the 3/32 ″ hex key provided with the tool kit.
2. Loosen the two (2) clamping screws located at the front of the Cleave Blade Housing; turning them counter-
clockwise by ¼ to ½ turn is sufficient.
3. Turn the height-adjustment screw exactly ¼ turn clockwise. This will raise the Cleave Blade Housing and
re-position the blade to a new section of the diamond edge.
4. Re-tighten the clamping screws. These should not be over-tightened.
Figure 23 Screws Used in Height Adjustment
After adjusting the height of the Cleave Blade, perform a cleave to ensure proper operation. Check to make sure
that the Cleave Blade has not been raised so many times that the contact point is right at the bottom edge of the
diamond blade, or that the diamond blade “misses” the fiber completely. If so, it is time to replace the Blade.
When cleaving, the blade performs an initial moves from its starting position to one that is close to, but not touching,
the fiber. The distance of this initial move consists of the
Blade Pre-Cleave Advance . Ensure that the
Cleave Blade does not strike the fiber during the Blade Pre-Cleave Advance move, as this can easily
damage the new section of diamond blade. After the Blade Pre-Cleave Advance move, the blade should
oscillate for approximately 3 seconds prior to striking and cleaving the fiber. If incorrect, the Blade Offset must be
adjusted in the Tablet Controller. Every 10 step change in the Blade Offset will change the oscillation time by
approximately 1 second. Reduce the Blade Offset for longer oscillation times. In general, the Blade Offset is
modified to account for variation in the blade dimensions and or position of the blade, the Pre-Cleave Advance is
modified to account for fiber size (larger fibers being closer to the blade).
Cleave Blade
Housing
Height
Adjustment
Screw
Clamping
Screws