There are two companies, Briney Tooling and BADAXE Tooling Solutions, that provide side lock toolholders that address the runout issue (if you know of others, please comment below). Figures 1 and 2 show a conventional side lock. The tool is inserted into the holder and then the screw pushes it to one side of the bore. The difference between the bore size and the shank diameter create runout.
The Briney and BadAxe solution is to offset the bore as shown in Figure 3 and when the screw is engaged the tool is brought close to the centerline (Figure 4). How close is dependent on the amount of the offset, the shank diameter and the bore size.
How well does it work? We tested a 3/4" toolholder with ten different 3/4" carbide blanks, all within the H6 tolerance, and the results are shown in the chart below.
FULL DISCLOSURE: At my prior company I was involved in the original design and testing of what later became the Bad Axe Tool.
Bad Axe Tooling Solutions
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