Electronics Weekly
And before that time is available, so thought has to go into what arrangement is acceptable.
Find more cnc lathe project blogs here
It seems a shame to cut too many more new holes in the front, and certainly not too many big (~27 x 47mm) rectangular holes for the classic yellow no-volt releases that are fitted to hobby grade machine tools (left), excellent though they are.
These can be bought with a big red knob on the top (below right) with a mechanical latch that enables them to be used as an emergency stop as well.
There are also a lot of cunning switches (sometime ‘LA38’) – both push button and rotary, 240Vac and 12Vdc, that would fit through the three existing 22mm front panel holes.
The existing E-stop has to go as it is a locking type but arrived without a key.
On the subject of existing stuff, the three front buttons are powered by an always-on 12V power supply, keeping mains away from the front panel, and they operate a pair of relays which switch mains separately to the spindle motor and stepper motors. Actually, there is a tiny fourth button labelled override on the right had side, included to back one of the steppers off its end-of-travel switch.
As it stands, the E-stop works on all the motors and the two left hand buttons allow the spindle motor to be stopped properly for material changing – the spindle motor relay being wired as a no-volt release, but not the stepper relay.
BTW, can anyone see why it is done as it is (solid lines left) rather that using the simpler red lines arrangement (two additions, three cuts – excuse the rough sketch).
Separately switching the spindle off for safe material changing, and the steppers off for safe tool changing, is desirable.
What to do?
