Milling flats on an ER Chuck?

[old martParticipant @oldmart]

I have access to many spanners collected by the museum and have selected some candidates for a small ammount of milling with solid carbide endmills to be used on the er25 and er40 collet arbors. There are two variations, the short spanners are for up to 8mm endmills and the ones with the long (12″) handles for larger sizes. You can buy er40 collets in up to 30mm which is handy for specialist tools made with a parallel shank.

Also both mills have R8 spindles with captive drawbars and no alignment pins and they both have flats milled immediately below the lower dust shieldfor holding the spindle. The huge advantage of having two mills and two lathes makes these mods easy.

Glad you like APT products, I have bought from them for years and throughly recommend them.

[Pete RimmerParticipant @peterimmer30576]

I had to grind a MT4/ER32 collet chuck recently to make the flats fit into the drive socket of my MT4 spindle. i did minde on the surface grinder and it came out well.

[Author]

Posts