What Am I

[Brad93]

This is what mine look like

View attachment 355804 View attachment 355805

Out of interest who is the maker? Or is it your own design?

 

[Johnnybravo]

Out of interest who is the maker? Or is it your own design?

I think those were made by Index in Germany. I think that Index might have been bought out by Traub, but not sure. The makers details are unfortunately under the sleeve that I shrunk on to use them in a 32mm holder.

 

[Johnnybravo]

Bets that's one of those tools that gets used once in a blue moon but when you do use it I bet it's a time saver

Bought to do a specific job. Have been used twice since

 

[Mikes]

The ends of the jaws, or what we speculate are the cutting edges, are at 90 degrees to the tool's axis. There's no lead in to help it as it goes over the workpiece. So if would only cut on its end (and very badly too). On the picture Johnnybravo posted, you can see the very generous chamfer produced as the tool goes over the workpiece.

If we are thinking it is like an adjustable reamer, but inside out, we have to consider how the jaws are constrained in _both_ directions - the collars shown prevent the jaws moving outwards, sure, but what is to stop them moving inwards and then chattering badly as you first jam the tool over the end of the workpiece and they move outwards against the external restraint?

On an adjustable reamer, the grooves on the body are ramped and the blades are always bottomed out in those grooves, clamped from moving in or out by the adjustment nuts.

FWIW, I wonder if it could work as a kind of one way clutch - gripping as it it rotated in one direction, but slipping in the other.

The internal of the object is a cone in which the 4 jaws / fingers / cutters sit in conical slots so the diameter is altered by using the ring nearest the arbour to push them along the slots and the front piece then clamps them firmly back against this. Good and ridgid when Locked-up I would assume.

 

[Mikes]

Thanks for all of your thoughts gentlemen. Perhaps it's just a conversation piece. Must admit that it could be the predecessor of Jonnybravo's one.
I don't think that I will ever have a need for it so if anyone does please shout as your most welcome to it FOC. Only saved it from the scrap skip as hate to see waste.

 

[Brad93]

Bought to do a specific job. Have been used twice since

Well I know where to bring something when a similar situation arises.