Novamill - Mach3

[Deck36]

Hi All

I'm in a bit of a tight spot currently, and really need some help.

I have a Mach3 converted Novamill, which I've only recently had running. With just a few parts left to make, the HDD decided to die on me!

It never occured to me to make a backup of the xml file, so I lost all my settings.

If anyone has a Novamill with Mach3 controlling it, and would be happy to share their xml file, or settings, I'd be incredibly grateful.

Brian

[m_c]

The configuration file will be specific to whatever controller/breakout board is fitted.

Can you upload some photos of the inside of the control cabinet?

[Deck36]

Apologies. I've been posting all over the place and thought I'd already put the images up

[m_c]

That's a pretty generic Chinese BOB, however I'm not entirely sure of the pinouts.

I do however know the original Denford wire numbers, but they don't seem to match the hand written marks on the terminals -
57 - Home 2 (Z)
58 (assuming the 5 has fallen off) - EStop monitor signal
66
67
68 - Estop relay coil
78 - SGR (Spindle Go Relay)

66 & 67 would normally be the wiring numbers for part of the E-Stop loop (depending on the spec, the EStop loop can go through EStop button(s), limit switches, Guard interlock, and spindle motor overheat, with the wire number incrementing between each switch/sensor capable of breaking the loop).

This is the BOB, which will give you the pin mappings

[Deck36]

I'm going to open the box up and see if I can trace some of those wires/numbers

From the BOB pinouts and looking at the wiring I have set the following:

66 - X Home
67 - Y Home
68 - Z Home ( however this one doesn't show in the diagnostics panel as being made at either end of the Z axis travel)
57 - E Stop
58 - Ground

[m_c]

Z Home should be near the top of the travel.
I can't remember how far off the top (I sold my Novamill a good few years ago), but it's definitely near the top.

I'm guessing homing was working OK before the PC died?

[Deck36]

Homing was non existent before the HDD died.

I could drive right up to, and past the switches on all axes.
The only way I was able to work was with soft limits, but if there were any problems with references I would lose my absolute position and have to start again.

Right now I can see LED's for X and Y light up at M1 Home and M2 Home but not for the Z axis

[m_c]

I can probably guess why homing and limits don't work then.

Denford for a while used inductive NAMUR sensors for homing, which are a sensor type designed for volatile atmospheres (basically a two wire sensor that changes resistance/current flow, so any wiring faults don't result in sparks). These are not easy to interface, but the original controllers used them, so I'm guessing whoever done the retrofit probably never changed them.
Instead they've probably modified the limit switch wiring to use them as home switches, as the limit switches would have originally broken the E-Stop circuit, but then they've never really implemented them. Or possibly disabled them because the Z has gone faulty.

Before you dismantle anything major, if the machine still has the big Harting multi-connector for connecting the machine to the control box, unplug that and very carefully look to make sure all the pins and sockets are in position and the same height. I've seen them become unseated, so they don't make contact.

[Deck36]

The homing situation makes a lot of sense now, from what you've said. Can the physical switches be used for homing or is that impractical?

[m_c]

There's no reason they can't, if they've been re-wired.

For the size/power of a Novamill, you can probably get away with using the limit switches just for homing, then relying on soft limits.
It's not like a Novamill axes have enough power to do any damage if you run into the end of the physical travel.