Denford Mill Comparison

[Manny]

hi Just a quick question I am getting a starmill that has mach 3 on it , could you advise what tool probe do you use and how did you set this up with the machince. Mine has the original controller board and can see a spare connection for the tool probe, next to the xyz datums ?

Thanks

[depronman]

I made my own
Basically a 6mm ball bearing silver soldered on to a piece of silver steel about 2” long
The other end is threaded m4
It screws into a piece of brass bar and the brass bar is bonded into a Tufnell sleeve (to electrically insulate it from the machine)
I then machined up a ‘tool holder’ with a slightly tapered bore and three adjusting screws at 120deg spacing
The Tufnell sleeve is a tight fit in the top end (small end) of the tapered bore the opposite end of the tapper is a piss fit in the Tufnell sleeve thus allowing the three adjustment screws to be used to centre up the ball of the probe
On first use a dti is used to clock up the ball using the three screws similar to clocking up a part in a 4 jaw Chuck
Thereafter unless the probe is knocked it runs true after repeated tool changes

In use a crock clip is used to add power to the probe and when it touches the work it completes the circuit and trigger the controller
Obviously only works on metal work
On none conductive work then sticky aluminium tape is used connected to the machine with a crock clip

The accuracy as proven very good I clamped a 30mm bore bearing on the bed and probed the bore adjusting the ball dia in the probe settings until the bore was measured as 30mm dia
The ball is physically 6mm dia, in the software it is recorded as 0.05 different to 6mm

It will repeat the 30mm bore measurement within +/- 0.01 over 20 tries which more than good enough for my use
It will also probe in Z
I have a tool height probe which is insulated from the machine so I need a opposite polarity crock clip for probe to tool height setting block
I use the probe as my reference tool
Then set up all other tools height as a delta to the probe and load these into the tool table using g43 on tool change to load the tool heigh delta
This has proven very effective so far and saves having to touch off the tool every tool change but does need a number of R8 tool holders with the commonly used cutters pre loaded

I must admit the boxford vmc190 that I now have is much easier on Tool changes as it as a manual drawbar and tool holders with pull studs - nice

Cheers. Paul