Testing and adjusting the optical plummets installed in tribrachs is usually time-consuming and difficult. With our adjustment device, you can reliably check your tribrachs yourself. The special feature of this new adjustment adapter is the very sensitive 45" minute bubble level and the claw connections on both sides.
Steps for testing and adjusting the tribrach circular level vial
Required tools: tripod, adjusting device
The tribrach is placed on a tripod and secured. Then insert the adjusting device into the upper part of the tribrach, lock it and align it with a foot screw. Now adjust the tribrach according to the circular bubble (disregard the circular bubble).
Turn the leveler by 100 gon and level the tribrach again with the other two foot screws. Then turn the leveler back by 100 gon and level again with the first foot screw used (if necessary). The tribrach is now precisely leveled.
If necessary, the circular level of the tribrach is then adjusted as precisely as possible to the center of the printed ring.
Steps for testing and adjusting the tribrach plumb bob
Required aids: tripod, adjusting device, additional tribrach, target cross on the ceiling.
The auxiliary tribrach is placed on a tripod and leveled. Then place the alignment device in the upper part of the tribrach, lock it and place the tribrach to be tested (with plumb line) on the alignment device with the base plate facing upwards and also lock it. Both tribrachs are now moved until the optical plummet is aimed at the cross on the ceiling. Only now tighten the stem screw of the tripod to fix the auxiliary tribrach.
Important: The auxiliary tribrach on the tripod must be leveled very precisely.
Now carefully rotate the tribrach to be tested by 200 gon, making sure that the crosshairs do not move out of the center of the crosshairs of the optical plummet. If the optical plummet is misaligned, use the adjustment screws of the plummet to carefully adjust out half the error and turn the tribrach back to its original position by 200 gon. These steps are repeated until the crosshair of the plumb bob no longer "dances" around the target cross, but remains cleanly in the center.
Note: Please note that the very sensitive circular bubble of the adjustment device may also need to be adjusted before starting work due to transportation, storage or climatic changes. This is also done in the tribrach on the tripod by aligning the bubble level parallel to two foot screws. Then check the adjustment device for reversal (turn by 200 gon).
If the bubble "wanders" during this process, half of the error must be corrected with one of the two foot screws and the other half of the error must be corrected on the adjustment screw of the bubble level using the Allen key supplied.
