[peter.blais]

Hi guys.

I'm in the planning stages of adding a lathe. One possibility I'm considering would be a new ST-20.

Anyways, what are your guys thoughts on the bar feeders? One of the parts I'm adding this machine principally for is like .25" worth of bar, and quantities of 500-1000pc at a time.

The servo 300 just seems like a lot of dough, for what it really does. Has anybody weighed the pro's and con's of simply purchasing a used bar feeder (smw, etc- ). Or even a bar puller and a tube / guide setup for longer bars.

I'm low on manpower, with me setting up and running the machines as well as designing / researching / testing parts- so I'd like it to run as unattended as it's possible when turning Ti.

We are a small company started by 2 guys a year out of college, so money is still a major factor. It looks like I can buy a used bar feeder for 2-5 grand, rather then 13k...

Another unrelated topic- We need to turn runs of small Ti parts. Would you guys purchase a haas for this, or look for a used okuma / mori / etc. I've already got a VF-2 so there's some desire to stick with it / keep it in the family. At the same time, $80k looks like it would buy a pretty solid used machine. I'd appreciate any advise / input into this subject as well.

Thanks in advance,

Peter

[SD man]

I would stick with a bar puller until you are sure you have enough work to pay off an expensive barfeeder. The servo 300 is nice because it is interfaced thorough the haas control. To interface let say a LNS barfeed would be possible but you have to control the barfeeder though the LNS interface instead of directly on the haas controller.\

[swain]

Peter,

I have used a haas SL30 / 300 bar feeder for 11 years straight.

In short...yes I have had some problems. Nothing that I could't fix, design around ext.

It works far better on stock over 1 inch with the .75 push bar.
When putting the .375 push bar on, its a good idea to make damn sure the machine is lined up, no slight kinks in the bar ect. Any little thing will turn the .375 push bar to a potato chip.

With all that being said....I ran a job a while back of 800 units, with about 10 pieces per unit being made from .5 brass round material when the machine was converted. With 8000 pushes, I would have to say 20 or less service calls due to the bar feeder messing up. The hardest thing to figure out was to keep new plastic washers in the push tube so that the material would not "slide" past the push point....using the washers as traction so material would stop when the push rod did.

I have never used a bar puller....so i can't help you there.
Take what i said on the Hass 300 with a grain of salt....that was just my experience with it.

Good Luck.

Swain

[double a-ron]

In my opinion, never buy any machine new. Your paying for that 3 letter word. Our shop bought our first machine new (haas minimill 2) and with the money we spent , $60,000, we could have purchased the machine we really wanted for the same money. Like a vf-3. We learned from that experience and bought our second machine used, a 2002 tl-15. We paid half what that machine cost new. If your budget is 80,000 check this out...

LT25-M: 7 Axis | CNC Lathes| KDCapital

I would be totally ok with switching brands especially if what we're talking about is a machine in a whole other class for less money than a new Haas.

[peter.blais]

Well-

If I was gonna buy used, I'd be looking for something less then 10 years old- and pretty low hours. The last thing I need is a 5 ton paperweight.

I've been back and forth on this soooo much. When we bought our VF-2- I mean it only cost us like 10-15 grand more then similar machines with 5000 hours on the spindle and we bought it new. Seems like the lathes though are more dough new- I think the bar feeders jack up the price, but don't have much resale value perhaps.

I also don't like the idea of buying used sight unseen- but out here in utah it's slim pickin's for local machines FS. All i can find at the moment, for example- is a SL-30 with 20k hours on the spindle, or a little daewoo lynx with 2000 hours and a feeder.

After that, it's vegas, az, etc- all like 500+ miles.

I've also just heard the haas's are a little light duty for Ti work. Seems to be an equal amount of people who say they work fine for that- so in the end I dunno what to think.

[double a-ron]

I know that machine seems old and ragged, but look closer. First it's an okuma not a Haas, had that been a '95 Haas I wouldn't have bothered. Second, it's a lathe not a vmc. Lathes tend to be programed, set up and operated by people who really know what there doing and they are usually dedicated to one job for long periods of time. All that minimizes how many oops might have happened. As far as spindle hours go, what is that really showing you? If they ran steel all the time the spindle probably wasn't running wide open all the time, but if they ran mostly alu., then like me they most likely turned off G96, dialed up 4 grand and let her rip for 8 hours a day.

I don't blame you for not wanting to by something without looking at it first. We didn't. Our lathe was located in Mississippi and we are in Miami. The machine broker arranged to have the machine powered up, and we had a tech from a local HFO check the machine out. I'm sure any other machine tool builder would do the same.

As far as Haas being light duty for ti work, I think you said you were planning on turning .25" dia. right? That's well within the capabilities of a Haas. If a Haas couldn't turn .25" anything I wouldn't own 2 of them. My only concern is your going to want something with some spindle speed, not horse power. Like an sl 10 or an sl20 with the 7k option. Or maybe look at a Star, Citizen, or Tsugami swiss turn. Those things were made for small Ti.

[peter.blais]

Actually, I was refering to the length of bar- the parts are closer to 1.5" OD. Still should be fine though.

It always seems to me that lathes take less of a beating then VMC's-

To be honest, I've made these parts before on a buddies old hardinge CHNC-II, which is about a $3000 cnc lathe lol- but he spends far too much % fixing the pair of them.

I think I am sold on the used machine route- Now I just need to figure out what to buy haha. I do like the haas route just because if it breaks, there's 50 zillion other guys running haas machines- the HFO is like 5 minutes from us, everything is just really convienient and easy. I don't really have a need for live tooling at the moment, so perhaps something like this:

Haas SL20 1999 CNC Turning Center Lathe Chucker - eBay (item 370400935756 end time Oct-22-10 13:00:17 PDT)

I could buy something like that outright fairly quickly, rather then financing it.

[double a-ron]

Looks good, don't forget to cough up some dough to have the machine checked out. Like you said you don't want a 5 ton paper weight. Just because the paint looks pretty that doesn't mean everything's kosher. My only other piece of advice is this, get live tooling. Live tooling on a lathe is like the probe on the mill. If you don't think your going to need it your wrong. We went from a manual lathe to a dual spindle cnc lathe with live tooling and bar feeder. Quite a big jump. I didn't think we needed half the stuff on that machine, but wouldn't you know first job we took in used all of it. Someone on here said something smart recently, "buy for the future not the past or present", or something like that. It's good advice.

[Geof]

....I ran a job a while back of 800 units, with about 10 pieces per unit being made from .5 brass round material when the machine was converted. With 8000 pushes, I would have to say 20 or less service calls due to the bar feeder messing up. The hardest thing to figure out was to keep new plastic washers in the push tube so that the material would not "slide" past the push point....using the washers as traction so material would stop when the push rod did.......Swain

I was reading through these posts and this caught my eye. Do you mean that during the run of 8000 parts you had 20 service calls on the Servo 300? In other words an average of 400 pushes per service call?

Surely not!

Also to solve your sliding past the push point why not push to a stop? We have several shop-built hydraulic barfeeds that work this way. They did not cost us 6 grand apiece and they do a lot more than 400 pushes before needing servicing.

[underthetire]

Word of cation on linear bearing lathes. One whack in to the chuck and they are usually toast. The linear guides can't handle a lift off from a 3 jaw. Collets are fine. I will always say Mori or Okuma for turning, but older Okumas can be a problem with drive unit replacements now. Real expensive. At least with most of the Mori's, they were Fanuc, stay away from the Yasnac ones, and the later Mitsubishi ones seem to be ok, with the mapps 2 panel and later. Don't get a CL with a touch panel, those are a real PIA.

[swain]

I was reading through these posts and this caught my eye. Do you mean that during the run of 8000 parts you had 20 service calls on the Servo 300? In other words an average of 400 pushes per service call?

Surely not!

Geof,

No...that might have come out wrong. 20 service calls over the 12 year life of the bar feeder, and 18 of them were one month or less after it was set up to stop a double push problem they had. Changing the control box fixed that.
In fact...thinking back...the bar feeder did the 8000 pc job with no problems at all.

I have been doing almost nothing but bar fed jobs on this lathe for the last year...and the piece count is way above 10,000 for 2010 ....its like a timex now.

Swain