One of the most common questions I get as a manufacturer of flexible shaft machines is: Why is my flexible shaft handpiece getting hot?
When it comes to utilizing a flexible shaft handpiece for tasks such as jewelry making, woodworking, or any detailed crafting or repair work, experiencing heat build-up can be a common yet troubling issue. The heat not only makes the tool uncomfortable to hold but can also indicate underlying problems that may affect the tool’s performance and longevity. Let’s delve into the reasons why a flexible shaft handpiece might get hot and explore some potential solutions.
Over Lubrication of the flexible shaft.
Cause:
One of the primary reasons a flexible shaft handpiece gets hot is grease migrates down into the handpiece when it gets warm. The grease invades the inner workings of the handpiece and fowls up the bearing raceways which generates heat when they are run.
Solution:
To prevent this from happening you should hang up the handpiece when done so that the handpiece is held vertically with the bottom end facing downward so that there is a loop below the handpiece. Or you can remove it and put it in a drawer. Always wipe the shaft end free of grease before you reattach the handpiece.
Most handpieces do not require lubrication. Just read your owner’s manual when you purchase the handpiece.
Many flexible shafts machines are over lubricated, and are not run-in properly. When you lubricate your shaft, you should apply a very light amount of high temperature lithium grease down to the last 6 inches and then stop. Replace the sheath but not the handpiece. Then run the flexible shaft at a high speed for 15 to 20 minutes to redistribute the grease while letting the end of the shaft hang down in an unlined trash container. This will let any excess grease run out. Then you can stop the machine and wipe off the shaft tip.
Improperly adjusted shaft extension
Cause:
If your key tip flexible shaft extends more than ¾ of an inch out of the sheath it may be forcing the shaft tip to rub in the handpiece or sheath. The handpiece attaches to the sheath not the shaft and if too much shaft is forced into the handpiece that will cause friction from the coiling of the shaft in the handpiece and sheath. (Note: Square tip type shafting does not require adjustment).
Solution:
Just adjust the key tip shafting extending out of the sheath by loosening the set screw at the bottom of the gray plastic motor connector and sliding the sheath in or out until only ¾” sticks out.
Worn Components
Cause:
Over time, the handpiece’s components, such as bearings, can wear out. Worn components may not operate as smoothly, leading to increased resistance and, consequently, heat. Bearings may have gotten wet or humidity might have corroded them leading to a rough feeling.
Solution:
Regular inspection and maintenance are key. Replace any worn-out parts promptly. Many handpieces come with user-serviceable components, making it easier to keep the tool in top condition. Keep the handpiece dry and clean.
