Drag Knife anyone?

[John S]

Yes I can see this but must be a pain to program as each entity has to be cut as an open line so it lifts off [ Z clearance ] at the end of each cut.
But if it does lift, then plunge down to do a cut at say 90 degrees to the first, how does the blade move round if it's just a swivel ?

Did a search on Ebay and you can get a simple tubular knife from the states with shipping for £115.

Cut Sign Vinyl - Drag Knife Bit for CNC Router End Mill | eBay

Marchant Dice sells the same item for £200

[boldford]

Yes I can see this but must be a pain to program as each entity has to be cut as an open line so it lifts off [ Z clearance ] at the end of each cut.
But if it does lift, then plunge down to do a cut at say 90 degrees to the first, how does the blade move round if it's just a swivel ?. . . .

I haven't any idea how the blade moves round either; however another thing that puzzles me is the very act of lifting off with thicker material combined with the shearing blade angle must leave a small triangular section of uncut material.
Could it be cutting from the ends of each line to the middle?
The device itself isn't too complicated to make but its use may well be far more involved than we think.

Any thoughts?