How to Take Care of the Whip

The whip is a bundle of cables. Specifically, the high pressure hose, abrasive hose and another two cables that sit at the back of the cutting head block. The two cables control the x-axis motion, the high pressure hose provides crucial water pressure, and the abrasive hose delivers the cutting particles. Thus, the whip is very essential to the machine operation.

In the meantime, the Whip is within the splash zone, and moving with the motion of the cutting head. In normal operation, the whip can withstand the splash of high-pressure water and abrasive. However, it cannot withstand direct impact from nozzle stream. To prevent the high-pressure stream from touching the Whip, the Whip is bundled up in a specific way. However, if in a rare occasion that the bundle deforms and moves unpredictably, there is a slight chance that it can be caught under the nozzle stream.

This guide will teach you the first sign of Whip deformation, and how to revert the whip back into the best shape.

Tools

Cable Tie (if needed)
Wire Snipper (if needed)

Procedure

Pull the cutting head to the front of the tank. Check if the whip gasket at back of the cutting head block is pulled out.
With the cutting head at the front of the tank, move it all the way left and right to check if the whip gasket at the back of the cutting head block is pulled out.

If the whip gasket is pulled out at any place, please sit it back in, and use epoxy or glue to affix it onto the cutting head block. We want the cutting head block to be sealed tight. If moisture finds its way inside, it can ruin the entire movement system.

After that, move the cutting head assembly horizontally across the top portion of the cut bed, and watch the whip bundle motion. All cables and hoses need to move in unison.

If you see any single hose or cable is spacing out, or its gap with other cables enlarges, we need to address the issue.

There is a 4-way cable holder that sit around 20cm from the tank gasket. Please make sure it is in place. There is also a small zip tie that holds the dry abrasive hose and high pressure hose together, please also make sure they are in place. Do not tighten these zip ties enough to pinch any hose
These cable ties are crucial to the machine operation, please do not take them off.

For example, if the high pressure hose separates from the other three during movement, then move the cutting head to the place where the widest gap shows, and pull the section after the 4-way cable tie taut.

Then, pay attention to the motion of the whip. We would like to see it move up/curl up when the cutting head moves to the rear section of the tank.

If you see the whip move down when the cutting head moves to the rear, it is most likely the torsional force of the high pressure hose doing the work.

Release the high pressure hose from the whip, move the cutting head back and forth, left to right, in order to make sure only the high pressure hose moves down when compressed.

After confirming the high pressure hose moves down when compressed, we need to release the tension. The way to do it is to flip the banjo fitting. Please refer to this page to loosen the banjo bolt.

After removing the banjo bolt, flip the banjo fitting to a position where you feel no torsion. Re-assemble the banjo fitting to the nozzle assembly.
ATTENTION: Clean the area around the banjo fittings before attempting this activity. Make sure no dust or abrasive particles find their way into the nozzle assembly/cutting head. Then tighten the banjo bolt to 18Nm.

Once the above step is done, put the high pressure hose back onto the 4 way cable tie. Again, try if the whip moves up when the cutting head is moved to the back.