Allan – thanks for the Pictures. I have been thinking about making something similar for my 9" Southbend Lathe (I think specified as 4-1/2" swing in England). It is fitted with Tool Holders that sit on an Adjusting Rocker (sometimes called a "Boat"
. I have no Problems with Turning Tools, but my Boring Bar Holder is useless. I have seen various designs in the past in both Model Engineer and Live Steam (a US Magazine). Yours appear to be similar to an Article by L.C.Mason in ME dated 2. Jan 1970, except the Clamping Bolt is on a different Face.
Do you have a dedicated Tool Holder for Boring Bars ? I have seen another design in ME which had a plate silver soldered or welded to the front of the Slot to prevent the bottom portion of the Tool Bit Slot from bending down. Have you noticed that on yours ?
Would it be too much trouble for you to supply the following Information ? The measurements can be Scale, not down to the last thousandth.
diameter of Post
overall dimensions of the Tool Holder
what size Tool Bit do you use ?
dimension from bottom of Tool Holder to Tool Bit Slot
Tool Bit Slot height
dimension from Tool Bit Slot to top of Tool Holder
size of Tool Bit Clamping Screws
thanks in advance, Bruce