It's in Model Engineer's Workshop magazine issues 16 and 17.
Basically it can address the use of a tool post grinder because Derek Brooks used a router.
In addition, there is another 'Quorn' type T and C which is the Bonelle.
Both designs do not require castings in the construction.
Whilst I have a Quorn, I also have a Stent which is essentially a small Clarkson. This Stent is rather unusual in that it should have been made from castings available from Blackgates in England but mine( I didn't make it) was fabricated from mild steel sections- welded up.
Norman