Graham

When as suggested by Brian testing the collet fit in the bored taper make sure you have a max size ground rod in the collet, saves it collapsing at either end to match an incorrect taper.

Emgee

Not totally familiar with the tool but from the figure you are using I would assume the pivot is 5" from the micrometer adjuster.

If so you need to offset by 0.703" or if it works like a 5" sin bar 0.696"

Edited By JasonB on 26/10/2015 20:23:06

I use my DRO readings to set up tapers. But that depends on the toys your DRO has.

Hi Graham

You have to be carefull with the trig functions on calculators because the default is radians not degrees.

HTH

Cheers Michael

When I make the internal taper for ER collets, (So far have made at least seven) I do it the quick and nasty way by setting over the Topslide by 8 degrees (maybe my Far Eastern graduations are better than we think). Then, horror of horrors, I wrap a strip of fine emery around a collet and polish with the (collet+emery) in the new taper.

DON'T press too hard or the tapers will grab!

So far am unaware of having had any problems with collets not holding drills, end mills, taps, or work.

It may be a bit crude but seems to work.

Howard

Howard Lewis:

You have reminded me that I drew attention to an effective and accurate way of setting the topslide in an earlier thread. See:

http://www.model-engineer.co.uk/forums/postings.asp?th=85534

If the aim is to get as close to 8 deg as we can with our equipment, then the conventional graduated scale on a topslide, regardless of its origin, is not the most certain way to achieve it, as I sense you would agree.