citizen C axis question.

Hey guys I have a quick question about engaging the C axis on these machines.

Sometimes the material gets really tight in my guide bushing because I'm trying to keep really tight tolerances, and sometimes I have to twist the material by hand to get it to slide through the guide bushing.

I have found that If I engage the C axis it prevents anything from rotating and it makes it easier to twist the material to slide it through a tight guide bushing.

This guy at my work keeps *****ing at me because he is saying that I'm putting stress on the servo motor but I keep telling him its bull****. When the C axis is engaged everything seems pretty ridgid to me and I would think that It would have to be for machining purposes.

How do I explain to this guy that I'm not putting stress on the servo motor?
Or is he right and am I an idiot?

I learned on a hanwha and this was a very common procedure but now that I'm on a citizen I'm a little out of my element.

It does put stress on the servo motors but nothing id say would be very detrimental..

However, I have to question why you're doing this anyway?

Load the bar, close the main and feed it through.. I run my guide bushings quite hard too, and depending on the job there's almost no way I could get the bar through by hand. What if you're running non conform material? How are you gonna twist it through? ..perhaps I'm missing something.

well sometimes I go to put the machine into the start position. and then you have to push the material up to the back of the part off tool. And if the guide bushing is kind of tight I just engage the C axis and then I can twist the material and push it through. otherwise you have to dick around with trying to touch the material off on the the back of the part off tool and hope it doesn't slide around when you go to set the start position.

you would be suprised how tight you can make the guide bushing and still push the material by hand if you rotate the material and push at the sametime.

Infact this is how I was taught to make sure my guide bushing was adjusted correctly. If you can't rotate the material by hand with the C axis engaged then you guide bushing is too tight. This is how I ran my machines and I could hold tolerances of + or - .0002 and this was on a Hanwha,
So far from what I have seen Citizens are much more precise machines and will hold even tighter tolerances. They are higher quality.

I still don't follow.. I don't understand why you would go to start position before loading the bar, and if you're in start position unless your part length is your entire z stroke there's not going to be any room to feed it through.

Put your cutoff tool in position point
Load bar
Close main
Jog z forward and feed material through
Cut off material
Open main
Start position.

And yes, I know its considered "too tight" if you cant move it at all, but +/-.0002 is still .0004 of variation, which is too much for me.

If my main isn't slipping and the material isn't jamming in the guide then I don't care about "too tight"
I've been at this for years and have yet to have any problems, you don't need to tell me and I'm not surprised lol.

ya i guess all that makes sense. this guy at my work was saying if you tighten the main to much it will wear the fingers out. you ever have that problem?

Believe me, you will wear the fingers out anyway.

thanks guys

I learned from old screw machine guys; told me to set the main by tightening until the chuck fingers break and then back off a bit.

Obviously its sarcasm, but you get the point. Depends on your material too, but for the most part I run the mains tighter than.. well, I won't get into that on this forum.

Never had to replace main chuck fingers, nor have I broken them. I have had to replace sub spindle chuck fingers though, but that's from issues not related to how tight the chuck was set.

believe me I run things tight so i know exactly what your saying. but there are times when i ran things not so tight it just depended on the job. but that was my old job where i worked for five years. but now that im at this new place i dont want to rub these guys the wrong way so im just trying to make sure i know my stuff about citizens.