Chuck scroll cleaning tool

[Bony]

I frequently use my lathes to bore holes and the chuck scrolls invariably fill up with swarf and clog up operation of the chuck jaws. This simple tool will quickly clean swarf from the scroll.

Remove the chuck jaws, insert tool at the outer edge of the scroll and wind in the mechanism as if the tighten the chuck. The scroll will engage the tool and the scroll thread will draw it inwards, clearing out swarf, oil scum and dirt etc as it passes the serrations. It works extremely effectively.

The tool is accurately machined from a scrap 3mm thick aluminium plate. I used aluminium because it was handy, machines easily and won't damage the chuck. This particular chuck is 200mm in diameter with 4 jaw self centering jaws and the scroll thread is 4mm wide and 4mm deep. It's important make the tool fit the scroll accurately, so each slot is exactly 4mm deep and 4mm wide. Using a 4mm end mill makes machining very simple.







In the above photo I have a piece of wood lightly securing the tool in place and all I have to do is use a speed winder to draw the tool over the scroll (saving dozens of wrist movements otherwise needed with the chuck key). The first time this is done expect the winding in process to be quite difficult as the tool beds in and wears a bit to conform with the scroll, especially if you've machined it accurately, thereafter it's a breeze. You may have to withdraw the tool several times to clean off a build up of swarf etc. I machined both ends of the tool whilst the mill was set up, the alternate end could be machined to fit a different chuck.

A separate tool is likely to be needed for each of your chucks, depending on the size of the scroll thread.

Nothing else I've tried works as well as this tool. Just do it!