Hello.

I have a 260VMC converted to run on Mach3, so I thought I'd add a bit to your thread...
They are a good machine within their limited capabilities, I've cut aluminium, brass, PB and hardwood on mine. When I get coolant fitted to it I'll be having a go on some steel, so if any other readers have a 260 fitted with coolant I would like to know where the tank went and so on.
The facility to swing the head round 90 degrees makes it a horizontal borer, a shame that there is no way of clamping the head at some intermediate angle (future project?)
I've had no problems with the existing proximity home switches, their repeatability is not an issue on my machine. The Z axis is controlled by a drilling (dimple) near the top of the column. As to the spindle taper I can't help you, because I've never had the easychange chuck off. From your photos it could be a modified INT 30 without the driving slots/keys or a shortened MT3....some measurements would throw more light on that issue. Is the disappointment about it not being R8 because you have a heap of R8 stuff? Collet chucks and so forth? Well, with the Z to the top, there is barely room to get an R8 collet chuck up the spindle from the top of the table without a tool in it and then of course there is no spindle lock so it would be impossible to tighten the collet nut. What I had to do was bite the bullet and BUY (not a nice word in a Yorkshire Lad's lexicon) an easychange ER25 collet chuck and a set of collets.
My tool carousel is lurking at the back of the workshop somewhere as I saw no good reason to keep it, if the user can't pick the correct tool in its holder from the cupboard under the machine when the software is yelling for a toolchange, then he shouldn't be driving it IMO. And anyway I wanted somewhere to park the monitor.
To digress a little, I'm in the latter stages of converting a Denford Easiturn3 to run with Mach3 and I required more inputs than your average BOB has, so 2 parallel ports and 2 of Peter Homanns MB-02 V6 BOBS filled the bill, the 1st BOB is normally jumpered (5 inputs) but the 2nd BOB is jumpered to give inputs on pins 2 to 9 as well as the usual 5, giving me a grand total of 18 inputs. As and when I get round to it I'll be having an MB-06 in the 260VMC and another stepper driver to run the 4th axis (under construction), and have the jog buttons on the front panel working again. This seemed easier to me than PICs or Modbus, being a humble MechEng, not a programmer.
Get yourself some 1/2" x 6" aluminium, drill and tap M6 holes on say a 20x20 matrix for a "sacrificial" fixture plate, surface or flycut both sides on your machine, add dowels underneath to drop into the T slots, then beg, borrow make or buy a verticality detector AKA a spindle square and check the column to table. Mine is a few thou out on the Z (another job on a long list) but was easily adjusted along the X axis. If you do have a crash into the plate it can always be surfaced again, which is better than looking at a part-pocket in your table. Not mine, fortunately, but I know where there is one.....
Elsewhere on this forum someone mentioned X+, X- Y+, Y- etc travel directions. If these appear to be wrong they can be reversed in Mach3, its in the config menu, under "Home/Limits", first column.
Link: Peter Homann homanndesigns.com/store/index.php
Keep up the good work, I'm looking forward to the next installment !
Regards,
John
In North Notts.