Supporting long thin work.
Sometimes it is necessary to do work on the ends of long thin pieces of work. This work can pass through the headstock and can protrude out the back. However, such a set up must be run at a very low speed since at high speed there is a danger that the rod may whip around, which is a hazard, and become bent..
My first solution to this problem was to add three M4 screws to my rear spindle extension. These screws can be used to centralise the work in the bore of the spindle.
This photo shows a piece of 4 mm brass rod centralised in the spindle.
This works well provided the work is not much longer than the spindle.
The screws are removed when not being used. This is for safety reasons and because they prevent access to the change gears.
This works well provided the work is not much longer than the spindle.
The screws are removed when not being used. This is for safety reasons and because they prevent access to the change gears.
The header photo shows a simple fixture that can be used to stabilise longer pieces of work.
The finished extension tube is shown here. It consists of a length of 20 mm steel tube that is a close sliding fit in the bore of the spindle. The tube has a 1 mm wall thickness. (This tube is readily available at B&Q stores in the UK).
On the right hand end a steel ring has been pressed onto the tube. The ring is 12 mm long, 38 mm OD and bored out to an interference fit on the tube.
On the right hand end a steel ring has been pressed onto the tube. The ring is 12 mm long, 38 mm OD and bored out to an interference fit on the tube.
The steel ring has been drilled and tapped radially for three M5 socket head screws
This shows the extension being used to stabilise a 500 mm length of 5 mm steel rod.
The extension tube is gripped in the spindle by the three M4 screws at the end of the spindle.
The extension tube is gripped in the spindle by the three M4 screws at the end of the spindle.