Hi Brian, also called a collet block, they usually use a 5C type collet,Are Stevenson's blocks known by other names outside the UK?
Hi Brian, they where developed here in Australia by Joe Hovel & his mate Peter with the help of Felix Wu (MagPro) for the manufacturing & distribution in mid 2017. I believe MagPro bought the patent or something like that or have distributions rights.Many thanks Peter, mine are the ER32 version. Very interesting about the 12 sided version, not come across any of those.
Hi Brian, yes small flats but they still offer plenty of support thoughThanks for that Peter, very interesting, I hadn't considered that the flats would be so small.
Many thanks for that Norman, I didn't know that . I am also from Long Eaton which, despite its Nottingham postcode is actually in Derbyshire.Incidentally, the late and lamented John Stevenson was English and lived and worked in Long Eaton, near Nottingham.
Perhaps it would be prudent to note this
Hi Jason, one of the other advantages of the 12 sided Joe block is that the nut does not protrude past the block & therefore can be held on a Magnetic chuck or using strap clamps etc straight on the mill table. If you have a height problem you could again mount it straight on the mill table as the back is precision ground at right angles to the sides. Vertically you could also mount it on the mill table a use a 2 piece vise, if you don't have one they are easy to make.Likewise the six sided block clamped by the flats and then the corners will give 12divs. You only need to work out the offset this gives once and make a note of it and then easily allowed for with the DRO.
Although the 12 sider looks to have some advantages it's larger size may not be so good for many who use them with smaller benchtop machines as shallow vice jaws may not come up to ctr line, reduced head height when stood vertically and more stick out if held in a chuck on the lathe