Hi Guys,
I feel a bit helpless at the moment when I cant track down a problem myself, but in act Im stumped.

I set up a simple turning job in aluminium on the weekend.
Drill a 5 mm hole through a 65 mm long piece of 20mm diameter stock.
Counter drill 50 mm deep to 13 mm ID.
Of course I took it in stages (8mm, 10mm, 12mm, 13mm)
When I took the part out of the chuck I noticed the 5mm hole was off centre at the 'other' end by almost 3 mm.

I set up a second piece of stock and drilled right through to 5 mm diameter again. Same outcome.
I used WD40 as a lubricant and drilled in small 5mm stages.

I set up two 200mm lengths of 6mm ground stock, one in the three jaw and one in the drill chuck in the tailstick so they almost touched.
I lay a straight edge along the top and there was no light gap so I assumed the centre lines are the same???
Maybe a bad assumption?/
So Im stumped.
I'm open and grateful for any suggestions please
warm regards
Brian
(PS Ive tried to upload a pic without success---sorry


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