Applies to machines built from August 2018
This procedure explains how to replace the compensating coolant union and the threadless transfer tube on the vertical 50 taper mill built after August 2018. This procedure can also be applied to the horizontal 50 taper mill built after August 2018. Skip the "50 Taper Mill - TSC - Threadless Transfer Tube - Replacement" if you only replacing the compensating coolant union.
|Symptom||Possible Cause||Corrective Action|
|A large flow of coolant comes out of the drain tube when TSC is turned on.||The union piston is not seated.||Put a high-pressure (small orifice) tool in the spindle and run TSC. The pressure should push the piston down. Or, disconnect the hose and use a screwdriver to gently seat the piston.|
|The amount of coolant flow from the drain tube is more than a few drops.||Runout on the carbide tip or damage to the piston cup seal||The 50T compensating union will bypass slightly more coolant than the 40T union, especially with tools with large orifices. This is normal. If the amount of coolant seems excessive, check the flatness of the carbide seals or check the piston for damaged rubber seals.|
|The union is leaking coolant.||Leaky drain tube or no air supply to the union.||The drain tube connection is not watertight and requires glue to seal it during union assembly, make sure the hose clamp is tight. Check the solenoid and hose for air supply problems.|
|The union makes a high pitch ringing noise when running TSC that does not go away after a few minutes of running.||TSC union alignment, or transfer tube runout.||Check the transfer tube for runout. Inspect the piston cup seal. Re-align the union with no hoses connected.|
|The union makes a high pitch ringing noise when running TAB that does not go away after a few minutes of running.||Excessive back pressure.||Try using a tool with larger orifices to reduce back pressure or try turning on TSC briefly to lubricate the seals. When running TAB with a small orifice tool, a high pitched noise is normal.|