Just wanted to confirm my thinking here, would appreciate any comments...
We have a 93 Hitachi Seiki HT20-SII turning centre that we recently bought used and brought online... Its got an 8" 3 jaw Kitagawa power chuck...
We were having some problems with parts being out of centre and it looks like this seems to happen whenever any kind of heavier cut is taken...
For example, current parts: 3/4" 316SS round bar, 0.1" OD turning depth of cut, 0.012ipr, 2500rpm, bar is sticking out about 3" from the chuck... at the end, we would notice between 0.01"-0.02" off center...
We have two of these machines, the other one with a new chuck... when looking how the jaws deflect when clamping, the old chuck looks to deflect noticeably more... also, we've measured that one of the jaws deflects less that the other 2, which makes sense, as we repeatable get the off centre drift to be away from this jaw...
So looks like its time to replace the chuck? Or just certain parts? (the master jaws?) Anything other thoughts or comments?
I'm thinking the whole chuck needs to be replaced...
Follow up question: how can i determine the mounting system? I believe A2-6 is standard for 8" chucks, so thats probably what I have... but I'm not really sure what A2-6 looks like, how can i confirm this? (Before I take off the chuck...)
Thanks...
We have a 93 Hitachi Seiki HT20-SII turning centre that we recently bought used and brought online... Its got an 8" 3 jaw Kitagawa power chuck...
We were having some problems with parts being out of centre and it looks like this seems to happen whenever any kind of heavier cut is taken...
For example, current parts: 3/4" 316SS round bar, 0.1" OD turning depth of cut, 0.012ipr, 2500rpm, bar is sticking out about 3" from the chuck... at the end, we would notice between 0.01"-0.02" off center...
We have two of these machines, the other one with a new chuck... when looking how the jaws deflect when clamping, the old chuck looks to deflect noticeably more... also, we've measured that one of the jaws deflects less that the other 2, which makes sense, as we repeatable get the off centre drift to be away from this jaw...
So looks like its time to replace the chuck? Or just certain parts? (the master jaws?) Anything other thoughts or comments?
I'm thinking the whole chuck needs to be replaced...
Follow up question: how can i determine the mounting system? I believe A2-6 is standard for 8" chucks, so thats probably what I have... but I'm not really sure what A2-6 looks like, how can i confirm this? (Before I take off the chuck...)
Thanks...