Semi-Automated Tissue Arrayers Troubleshooting

1. Stylus sticks inside of the needle

When a stylus starts to stick to the inside of the donor or recipient needle, remove it by raising it above and out of the needle. Clean with a paraffin solvent (e.g., xylenes or xylene substitutes). Thoroughly dry before coring another paraffin block. NOTE: Work with one stylus at a time, as the donor stylus is larger than the recipient stylus.

2. Paraffin cores appear to be compressed

Before coring, raise the stylus inside the needle. Subsequently, when coring the donor or recipient block the paraffin does not have to push up the stylus inside the needle as the core is made. This will result in producing cores that are not adversely compressed by the stylus (especially using a “sticky” stylus, see tip #1).

3. Paraffin cores are not removed when the recipient needle is removed from the recipient block

While coring your recipient block, and with the recipient needle at the bottom of its travel, gently tap the top of the stylus downward to slightly compress the paraffin core inside the needle. This will compress the paraffin core to the inside of the needle shaft. This slight compression will assist in the acquiring of the core by the needle when the blue lever is turned and help to sever the paraffin at the base of the core (rather than part-way up the shaft of the core).

4. Paraffin cores are not removed when donor needle is removed from the donor block

While coring your donor block, and with the donor needle at the bottom of its travel, gently tap the top of the stylus downward to slightly compress the tissue paraffin core inside the needle. This will compress the tissue paraffin core to the inside of the needle shaft. This slight compression will assist in the acquiring of the core by the needle when the blue lever is turned and help to sever the tissue-paraffin at the base of the core (rather than part-way up the shaft of the core).

5. The light won’t turn on

Check and replace, if necessary, the fuse and/or halogen light bulb.

6. The ocular reticle is not aligned with the center of the opening in the donor block (made by the donor needle)

Center the binocular component of the microscope using the adjusting screws.

7. The instrument is not leveled (the bubble in the front center is not centered)

Level VTA-100 by adjusting the leveling pads until the bubble is centered.

8. A needle is bent

Replace the needle and/or the stylus.

Problem	Solution
1. Stylus sticks inside of the needle	When a stylus starts to stick to the inside of the donor or recipient needle, remove it by raising it above and out of the needle. Clean with a paraffin solvent (e.g., xylenes or xylene substitutes). Thoroughly dry before coring another paraffin block. NOTE: Work with one stylus at a time, as the donor stylus is larger than the recipient stylus.
2. Paraffin cores appear to be compressed	Before coring, raise the stylus inside the needle. Subsequently, when coring the donor or recipient block the paraffin does not have to push up the stylus inside the needle as the core is made. This will result in producing cores that are not adversely compressed by the stylus (especially using a “sticky” stylus, see tip #1).
3. Paraffin cores are not removed when the recipient needle is removed from the recipient block	While coring your recipient block, and with the recipient needle at the bottom of its travel, gently tap the top of the stylus downward to slightly compress the paraffin core inside the needle. This will compress the paraffin core to the inside of the needle shaft. This slight compression will assist in the acquiring of the core by the needle when the blue lever is turned and help to sever the paraffin at the base of the core (rather than part-way up the shaft of the core).
4. Paraffin cores are not removed when donor needle is removed from the donor block	While coring your donor block, and with the donor needle at the bottom of its travel, gently tap the top of the stylus downward to slightly compress the tissue paraffin core inside the needle. This will compress the tissue paraffin core to the inside of the needle shaft. This slight compression will assist in the acquiring of the core by the needle when the blue lever is turned and help to sever the tissue-paraffin at the base of the core (rather than part-way up the shaft of the core).
5. The light won’t turn on	Check and replace, if necessary, the fuse and/or halogen light bulb.
6. The ocular reticle is not aligned with the center of the opening in the donor block (made by the donor needle)	Center the binocular component of the microscope using the adjusting screws.
7. The instrument is not leveled (the bubble in the front center is not centered)	Level VTA-100 by adjusting the leveling pads until the bubble is centered.
8. A needle is bent	Replace the needle and/or the stylus.