New Acer 3VS milling machine question

[jmarkwolf]

I have a new Acer 3VS milling machine. I love it.

I had a tired old Bridgeport that I was thinking about having refurbished as a retirement gift to myself, but it was significantly more economical to sell the Bridgeport and buy a new Taiwanese Acer.

One peculiarity I haven't been able to get a good explanation for, is the reason the spindle won't always start immediately after using the spindle brake.

There is a micro-switch on the lever, so the logic "knows" anytime the brake is actuated. Thereafter, it takes 2 or 3 tries to get the spindle to restart. It doesn't seem to be a "timeout" that has to expire, it just sometimes takes several attempts to restart. Thereafter it's fine until the next time I use the spindle brake.

Anyone have an explanation?

 

[JimDawson]

Micro switch sticking maybe?

 

[mksj]

Agree with Jim, probably an interlock switch which should deactivate the run command and also issue a free run command to the VFD. It may also be that the brake lever is sticking and not fully releasing so check the travel and check the switch. Do not know how the new control systems are designed, but with similar setups on the lathe the direction switch needs to be cycled through a stop position to reset the run relay.

I am sure Acer also have very good tech support, so that is also an option if you cannot fix the problem.

 

[ZZDOG]

HI THERE....
Just push estop in and release...
ZZDOG....

 

[jmarkwolf]

OP here.

I neglected to mention that a brake delay function is normal, according to tech support guy at Production Tool, where I bought the machine. However, he couldn't adequately explain the rationale for a delay on spindle restart, nor could he explain why the variability before the spindle would restart.

So far, I've only used the brake to hold the spindle when chucking up a tool. The spindle normally comes to a stop quickly, so I haven't needed it actually brake the spindle from speed.

I've been starting/stopping the spindle with the Forward/Stop/Reverse knob. The alternative is to leave the Forward/Stop/Reverse alone and wind up the RPM control on each spindle restart, which seems inefficient.

It hadn't occurred to me that the brand new brake micro-switch might be misbehaving but I'll play with the micro switch as suggested, and report here.

 

[ZZDOG]

HI THERE..
OK, were I work we replace the old Vectrax mill head with a new ACER head works real good...
Had almost the same problem you have with the hand brake...
1/ You can stop and shutoff spindle motor with just the hand brake... To restart spindle motor you would turn FOR/REV. switch to off...
and then turn back on to restart spindle motor......
2/ If you use the FOR/REV. switch to stop motor and then pull down on hand brake to change tool you have to push in estop and release
to restart spindle motor.....
The fix was to just lower the hand brake switch ......
Pic,s below.....