Figured out tonight why the keyway was shallow. I happened to stand on of the collets on its drawbar end and it wobbled. When I looked close you can see a slug with the drawbar thread has been inserted into th end of the collet. I wondered how you open out the centre cavity an now I know how this bunch did it. I had wondered why there was a coupl of stake marks in the bottom of the keyway. Again I now know - to sto the slug turning out. Grinding them deeper has exposed what I now kno to be the tops of the thread on the outside of the slug. Fortunatel most of the metric sizes are better made. I thought I was shopping wit a reputable dealer.
In case of any missunderstanding in view of my last post, can I make i clear that these were NOT supplied by Warco.
Pete
-- peterseage
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