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View Full Version : Sieg Mini lathe - smallest diameter rod turn-able?



HankMcSpank
17-11-2010, 07:42 PM
I have a set of ER32 collets, which are great for 4mm -20mm ...but I now need to hold very small diameter steel rod - like 1.5mm-2mm - is this doable on such mini lathes & if so, which route should I be going to hold the workpiece?

irving2008
17-11-2010, 09:29 PM
I've turned a short piece of 2mm by clamping it in a 10mm holder turned up then drilled out and cross drilled for a clamping screw. the issue is that any length longer than a gnats will see the rod bend with anything other then the finest of cuts. The solution is to use a steady.

There is a special tool (http://cgi.ebay.co.uk/SMALL-DIAMETER-TURNING-TOOL-SUIT-Myford-etc-/330443912709) you can buy for this... from Chronos or others...

M250cnc
18-11-2010, 11:13 AM
My preference would be a few small collets ER11 size they start at 1 - 1.5mm

The Myford gizmo from Chronos would be good for mass production but little flexability in varying the diameter

The other alternative is a bush that fits in your ER32 and you profile saw cuts to it similar to the ER collets

Phil

irving2008
18-11-2010, 11:36 AM
I think the way to use the Chronos tool is you turn up the work holder and bush together as a single piece and drill out, then part the bush off... that way you end up with a matched set of holder and steady bush...

M250cnc
18-11-2010, 12:15 PM
I think the way to use the Chronos tool is you turn up the work holder and bush together as a single piece and drill out, then part the bush off... that way you end up with a matched set of holder and steady bush...

I think i will have to disagree.

I see that the brass bush in the photo will have a hole to match the rod to be turned.

The whole tool will then have to be accurately set on the centreline in height of the tool and the X axis to align the bush with the rod

Then to get the correct turned diameter the bit is adjusted in the holder using a screw that is just visible at the back of the tool

Unless you have this tool and know better, that is how it looks to work.

Phil