Headstock counterweights...

[Dontech]

I have a 2005 Haas VF-3 and a 2012 VF-5 in our shop, among other machines. I also have a 1994 Leadwell MCV-1000 AP.

This Leadwell is ony a 6000 rpm machine but it's been a rock-solid performer over the last 20 years. The only problem we've had with it is a tendency for the counterweight chains to break @ every 7 years or so. It's happened 3 times in my time here. We've moved the machine since the last time it happened in 2014, and now it sits in a place that's more difficult to get a forklift in than ever before. Worked on it for 3 days and got the counterweight up with a little help from Joe Cocker and my friends. A repair tech is coming in today to replace the chains and get her back in business. This episode has produced a lot of discussion with management about the other machines in our shop. We've got a pair of 2001 Hardinge VMC-1000 II's that we know have counterweights because the chains are readily visible from the floor, but when asked I had to admit that I have no idea if Haas VMCs do too. There's so much in the way of enclosure panels up top of them, I'd have no way of knowing for sure without going up there and disassembling a bit...but I don't see a point in that if it's just for information. Y'all know how it is, though...when the Big Bosses ask for info, you provide it, so...maybe a dumb question because it would seems logical they would, but...do Haas VMCs have a counterwieght in the back?

Thanks guys.

[gcode]

1 hour ago, Dontech said:

do Haas VMCs have a counterwieght in the back?

it depends on how old they are

older models use counterbalances and chains

the newer ones I've seen use gas charged cylinders 

[cncappsjames]

Knowing as much as possible about the equipment under your roof is NEVER a bad thing IMHO. Depending on what types of repairs you do yourself, having knowledge allows you to prepare to have parts on hand, or if that is prohibitively expensive, you at least know what to order should that become necessary.

Your best bet is to contact your local HFO with your machine's serial number and date of manufacture (if known), and they should be able to tell you just about everything you want to know about your machine.

[Dontech]

Thank you, guys. Appreciate the input.

The tech is here now so I picked his brain about our Haas' and he confirmed they both have the gas system.

[Leon82]

Does the head come crashing down when it drops?.

We had an excell that would smash the head when the chain snapped.

[gcode]

8 minutes ago, Leon82 said:

Does the head come crashing down when it drops?.

my 90's vintage Haas did when the chain broke

luckily, the chain got jammed up and stopped the fall before the head crashed into the table/vice/part

[Dontech]

50 minutes ago, Leon82 said:

Does the head come crashing down when it drops?.

We had an excell that would smash the head when the chain snapped.

No, thank God, it didn't. It stayed put, and moveable with the MPG...but even so I thought it best to jog it down onto a 2 x 4 laid across our chuck to prevent it settling overnight. Wasn't sure if it would wreck the axis motor if it suddenly spun down or if it would fall down gently but didn't want to find out.

[Leon82]

3 hours ago, Dontech said:

No, thank God, it didn't. It stayed put, and moveable with the MPG...but even so I thought it best to jog it down onto a 2 x 4 laid across our chuck to prevent it settling overnight. Wasn't sure if it would wreck the axis motor if it suddenly spun down or if it would fall down gently but didn't want to find out.

That is actually good thinking. I have seen situations where the motor will move as soon as the power is turned on.

 

I got to used server motor for a old kitamura from our local repair guy. As soon as I hit the power button x axis went full speed and smashed up against the stop. He came back with another one and said you might not be able to get the nut on the end of it. It was clearly dropped and the shaft was dilapidated