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Drawbar thread

Hi, I am new to model engineering, apart from some lathe practice at school about 30 years ago so please be gentle with your replies.

I have recently bought an X2 mill and an ER32 Collet chuck. These are both threaded M12 the same as the draw bar. Looking at some more items like a slitting saw arbour I found that most are 3/8th or 1/2 BSW. My problem is I only have a metric lathe so can't make a new draw bar with an imperial thread. Is there someone who sells these or a soource that has M12 arbours anywhere.

Or is there a configuration with the change gears where I can cut an imperial thread on a metric lathe.

Reply to
Richard Bradshaw
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M12 Studding

Charles

Reply to
Charles Ping

Have you tried to get a long Allen bolt? I bought one for my Emco FB-2 mill, which uses M10 Allen bolt for its drawbar as standard. A 3/8 BSW Allen bolt was necessary after I got some accessories with that thread, so now I have both. At a pinch, a length of threaded rod could be used.

Reply to
Jordan

When the drawbar on my Holke broke I cut the old thread off and welded on the threaded bit of a high tensile bolt. It's lasted 10 years. Might be easier for you than making a new one piece drawbar and threading it.

Reply to
Dave Baker

Alternatives:

1) Use lengths of studding (threaded rod) of the right diameter/thread pitch 2) Get a couple of BSW threading dies to make your own

Depending on the change wheels that you have in your set, it may well be possible to get a close-enough approximation to a 3/8" or 1/2" BSW thread pitch. You aren't looking for extreme accuracy, so the pitch error over the dozen or so pitches needed to hold the chuck may not be a big issue. The "ideal" change wheel setup would need a 127T wheel, but for this kind of application that may well be overkill.

Regards, Tony

Reply to
Tony Jeffree

On Wed, 09 Jan 2008 11:07:27 GMT, "Richard Bradshaw" said, amongst other things, that::

The suggestion of using studding would be good, except for the fact that you would need either BSW spanners or to turn it down and put a metric thread on the end. I would suggest getting hold of a 3/*" and 1/2" BSW die. Turning the drawbars to the right diameter is not a problem (12.7mm etc :-). Then, having put the BSW thread at one end, thread the other end to suit your existing nut, or similar other metric one, eg. M10 or M12 as appropriate.

Alternatively, whereabouts are you?

HTH Mark Rand RTFM

Reply to
Mark Rand

Wots wrong with a shifter? -or am I showing my ignorance :-)

Archie

Reply to
Archie

Only major issue is that it's a pain to have to adjust one at head height, against a mill head with little knuckle room, every time you use it.

Mark Rand RTFM

Reply to
Mark Rand

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