The 6mm allen bit is slightly smaller than 1/4".
I buy a 1/4" allen bit, file a slight taper on the 6 edges of the tip.
Then hammer it into the rounded out 6mm hole, using heavy blows.
Then unscrew the bolt.

VW used many 6mm allen bolts on many of their vehicles.
I have used this method lots of times, including CV bolts.

Mark

On 12/31/2023 5:08 PM, Rick Cooper wrote:
> Hi all,
>
> I've got a noisy CV joint and thought I would remove and repair it today.  But I managed to round off one of the twelve 6mm Allen socket-head bolts so that I cannot break the last bolt free.  Unfortunately it is on the outside CV joint so it inaccessible by most tools.
>
> Has anyone had this experience and can offer any advice?  Am I stuck drilling out/off the head of the bolt?  And then how do I remove the shaft from the wheel assembly since it will be challenging, even with joint out of the way, to get a good hold on it with vice-grips?
>
> Thanks for any help.
>
> Rc