Thanks Guys. The tang of the knife is extended with a 5mm stainless threaded section. The tang sits inside a slotted dowl in the handle which runs most of the way through the bolster. Front of the bolster has a precise slot to fit the tang. To make the fit up very solid the rear of the knife has a specially machined brass sleeve which is epoxied in place and buts up against the dowl. The thread passes through this and my machined stainless screw goes inside this and pulls the tang in tight when tightened. This is like a large Corby bolt except I have used a brass sleeve into which it seats. The slot inside the dowl running through the knife is epoxy bedded making the fit very precise with no movement.
This is not intended for an interchangeable handle system. I can't see any use for this in custom knives and each tang would be a custom fit for each handle. It is simply so if in the future the knife needs serious thinning work, the blade can be removed, worked on and re-etched easily. Also It is yet a bit unproven how well the Bluing will fair in constant kitchen use and being handled constantly the bluing could wear away in a similar way to say the trigger part of a shotgun. This means I can easily remove the handle and etch the damascus part on the ferrule should the bluing get a bit thin and the pattern lost.
Although the fit is precise, I will use a smear of silicon on the base of the rear bolt and at the tang bolster to stop and moisture getting in and rusting the tang.
This was really a side effect of the precise fit up needed to have the bolster as a retro fit after the polishing and bluing, I could have left the bolt proud and ground flush as final finish, but it ended up being such a sturdy fit I thought why not leave it removable for future convenience.