In a tin of small lathe tools that came to me some time ago from a model engineering friend, sadly departed, were various unused Eclipse parting tool blades. Including a couple of rather neat , small blades, only 0.300 deep. I had no holder for these, and though they won't perform any task that can't be done with existing means, it seemed a pity to put them back in the tin - for ever?
I schemed out a simple holder in which they could be accommodated in a four way toolpost.
The final height adjustment to centre ht. can be made either by packing under the holder, or by sliding the parting tool along in its slot.
The Eclipse blades have a taper of about 6 degrees on the very top and bottom edges , which helps to secure them by a wedging action of the clamp. Also, they taper in depth from 60 thou at the top to 40 at the base to create the side clearance.
When I cut the slot in the steel block, I was able to use the little home made taper cutter that I had made long ago, for the blade slots of the Geo. H. Thomas rear parting tool holder kept at the back of the Myford cross slide. Where the parting blade meets the bottom of the slot, I left a 10 thou. land, about 60 thou. high, so that the blade stands vertically against the slot milled in the holder.
The separate clamping plate was made from 3/32" gauge plate, and milled with the tapered cutter to give a few thou of impingement on the parting blade when tightened down, between blade and the 1/8" deep land across the top of the tool. The plate was hardened and tempered.
Shown here on the Myford, in a ( sort of) GHT format of home produced four way toolpost, and on the Jack Radford design of robust alternative Myford top-slide, the making of which I wrote up some years ago on this Forum.
Sorry to state the obvious in this description!, but perhaps might be useful to someone getting together some basic tooling.. Dave
