HAAS Servo Bar 300 Push Speed

Good afternoon,

First post for many years, my old login must have expired as I used to haunt the Okuma forum with our LB15

So greetings to all.

We have a new to us HAAS ST30 with a Servo bar 300 interfaced to it.

The two items have been commissioned together as they were not originally from the same owners.

The issue I am experiencing is when advancing the bar stock with a G105 the bar is being thrown out of the chuck by more than the set figures in the barfeed setup screen.

We are running the standard chuck with hard jaws.

The bar stock is 2 3/4" dia 304 stainless Steel in cut pieces of 1 meter long, so some good weight to it.

On initial setup when first setting the bar reference position to the front face of the chuck jaws, the barfeed moves in a controlled manner, not to fast, then we can jog in V to set the reference position.
The G105 is then issues to advance the stock which it does correctly and the pusher exits the spindle tube so that it is approx 1 inch out of the spindle.

We run our part, and when the G105 is issued again, the pusher runs in at quite a rate, hits the bar and the stock can over advance by anything between 4mm and 10mm.

I have found that it is the pushers speed along with the mass of the material that is throwing this forward.

I do believe that our barfeed has been knocked back away from the lathe by a couple of millimetres.

If I override the machines Rapid by knocking it down to 50% or 25% then the pusher advances slower and the push length is more or less correct.

We had an engineer come in to sort a loading problem and he upped some parameter to speed up the pusher for some reason.

Should the pusher rapid in and keep that feed whilst connecting with and pushing or does it slow before hitting the bar stock to a more respectable speed?

I think it maintains that speed and this is the issue.

Does anyone else experience this and if so do you know which parameter I can change to either slow the pusher or have a default value that I can compare to whatever the engineer set ours to.

I ask here as I have contacted the engineer since and he has told me to alter a couple of random parameters, but so far, no reduction in speed.

We are forced to manually advance stock all last week, and if this is going to be a problem then maybe we should go back to a coolant driven bar puller, one bar at a time.

Anyones experience in this greatly appreciated.

Thank you.