Mortice bit

[mjcann]

Another bit of kit hiding at the back of the shed for many years, Record drill stand with mortice attachment, my question is, how much clearance should there be, between the auger and square chisel.
Martin

 

[Myfordman]

1p coin as a setting spacer between the chisel and the holder seems about right for me.

 

[custard]

Yep, a 1p coin is about right. But there can be quite a range of variation for different applications.

If you're trying to make a through mortice for example without leaving an indentation from the auger you'll probably start at about half that and put up with a much slower feed rate and lots of jams. If you're bashing out simple mortices in a cloggy timber like pitch pine then you'll likely add another 50% to that.

 

[mjcann]

Thanks for replies, its too cold in the shed now so I will give it a go in the morning and report back.
martin