Bandit stopped working

[Chris64]

The subject pretty much sums it up. Any idea's? Everything starts as it should but the servos never start-up. Normally they make a high pitch sound when they are ready to go.

Here's something strange. The system seemed to require air for the servos to start. I don't know why. There is a small black box that the air routes through and it feeds into the CPU case. I assumed this was a shut-off but it turns out that it is the timer that feeds the lube system. It has no feedback to the machine for whether or not the air is plugged in. So I'm not really sure how it would know if I had the air plugged in or not.

I tried just pushing all the cards down and checking everything but no luck. It seems to just not be powering the servo controls...the interface works fine as longs as you don't try to move anything and the spindle works.

I'm open to any idea's here. Thanks.

[HuFlungDung]

Sounds like no power to the drives, which means that perhaps an open fuse has occurred. Power down and unplug the Bandit, and pull all fuses and check fuse continuity with an ohm meter. That would be a start.

[Chris64]

OK...I tried that. All 1,000,032 fuses are OK...seriously 1,000,032 fuses. Well ok maybe 11...whatever. They're all OK and I had power to the main motor transformer. I slid out the single motor controller card and re-sat it (as you've advised many times before) and presto...it works now. You've always said this happens every couple months and I guess I was due.

I'm still ready to trade this in on something with some 3-d potential.

Thanks.

[cbucner]

I have 3 servo boards from a bandit I removed from a shizuoka cnc mill.
if you're interested please let me know, I also have some other parts from the same control.

[damelman]

If you have no fault light, I think you may have a bad air pressure switch.
The air pressure switch enables the control. I have two supermaxes in mothballs with Bandit controls one bandit II and one Bandit III.

[Chris64]

Where is this air pressure switch usually? I can't find it but the machine will not work if I don't connect air. I only found a solenoid that is controlled by a power supply in the CPU case (not sure what it's for). I'd like to just disable this switch.

I had the problem again yesterday but again just removed the main motor control board and slid it back in and it started no problem.

[HuFlungDung]

If your machine has a one shot lube system, I think there could be a switch there. If I recall correctly, there is a blow-out diaphragm on the lube plunger. If the diaphragm blows out, then the switch will be 'made'.

The diaphragm is just a piece of brass shimstock, maybe one or two thousandths thickness, similar to what is used for overpressure blowout protection in a CO2 cylinder for a paintball gun.

You will have to probe your way around the lube pump and see if you can discover what I am talking about. There should be a simple plunge switch opposite to a tiny protruding pin. Normal operation of the lube system means there should be a noticeable gap between the two, and a blown diaphragm means no gap will be present.