[namder1]

I have been machining for many years, both manual and cnc(VMC & bar feed lathe). However, never a screw machine. The shop I am in now is bringing in formerly out sourced parts and I feel they should be done on a screw machine. Most all parts are small and lot sizes run from 1,000 to 50,000 parts. My qustions are .....are these machines very hard to program and do you use normal software such as SurfCam or is there a particular software just for screw machines. Lastly,what is a good, reliable and affordable machine?

[underthetire]

I used to work for the Tsugami dealer, but I can't help with software. I will tell you to buy a Citizen. The Stars seem to be ok as well, and the Tsugamis were ok to, but I always told great things about the Citizens from my customers.

[gizmo_454]

Difficulty programming and complexity of the part to be made go hand in hand. I program our Citizen by hand, but there are supposed to be some decent software packages out there. I am not sure of their names...Maybe someone else can pipe up and spit some out...

Like your shop, our shop has CNC lathe and mill equipment. I found the foundations to be the same, for example, if you understand G/M code and have a pretty good idea what needs to go into the part to make it, it's not all that different.

On the other hand, it's the details that count:

Remember that you would be completing the part on one machine now, not 2, 3, or more. Setup times will be much longer. Jobs that I normally setup in our lathe for one op and then mill for a second op, may take 1/2 hour to 1 hour each setup while the swiss typically will take me 4 to 5 hours.

Also, swiss machines are typically smaller with smaller amounts of HP. Don't think this is your 30HP Mori or Okuma and try taking a 0.300" depth of cut at 0.010" feed per rev. Not going to happen! In fact, depending on the material, you may not be able to feed hard enough to break the chip. Stringers then become a problem. There are ways to deal with it, but experience with it will help bunches.

Unlike your typical turning center, you don't need a tail stock to turn long slender parts since the turning tool is literally less than an 1/8" from the guide bushing holding the material. I have had no chatter related issues on our Citizen at all.

Need hex or square material but can't find it in the type or size of material you need to use? Make it. Most swiss have live tools.

Typically, a swiss will hold much tighter tolerances than turning center. We turn our Citizen on in the morning, check the first part or 2 and then walk away for 2 to 3 hours running parts with 0.0005" to 0.001" total tolerances all over.

There are obviously more differences than I can possibly describe here. For the most part, like I was told:

"If the part is under 1-1/4" in diameter, it should be made in a swiss. I fully believe that based on my experience.

Good luck!

Mike

[namder1]

Thanks, guys big help! I recomended a Citizen to my boss and his boss wants a Tsugami.....sssshhhh.

[hacdlux]

i run a tsugami ss 32

of all the swisses you will probabbly find it has the smallest learning curve

your biggest trick is going to be convincing your boss to buy good stock you either want cold drawn or centerless ground depending on the tolerance of your part

tsugamis come with the abile software which is very intuitive for basic to intermidiate parts but you probabbly wont use it very long because it is faster to program by hand

i have to go in and bail my boss out now he hit the e-stop on accident

[namder1]

what about delcam????

[DCogswell]

Namder1,

Tsugami's are very sound machines, from ease of set-up and programming software to rigidity and reliability. I've got 4 Tsugami's, 2 of them are 20 years old and they are still running 24/7.

I also have 2 Citizens, and they are the most finicky and frustrating machines I've come across in a long time.

Personally, I've ran Stars, Tsugami's, Citizens, Tornos & Hanwha's. And I would have to say the only reason why I wouldn't buy a Tsugami is if there were none available and I couldn't wait for inventory.

What kind of parts are you looking at making?

[abgoel]

DCogswell - can you tell me in order of best to worse between Tsugami, Hanwha, and citizen?

[DCogswell]

DCogswell - can you tell me in order of best to worse between Tsugami, Hanwha, and citizen?

I would lean towards Tsugami for most applications however, I say that with personal bias. I have a lot of experience on those machines and I feel they have a very professional support system.

I don't have too much experience on later model Citizens so any opinion I might have would be limited. I have been running Citizen R04's for the past year and I'm not really impressed with them.

What kind of application do you have?

[littlebrewman]

i have run tsugami swiss turns before.they are ok.i currently am running 3 brand new NEXTURN and they are awesome!i use mastercam to program them with and i mostly run titanium and hardened stainless steel on them.they hold great tolerances and are well outfitted for tooling.i also run hangsterfers oil in them as well as ground stock.the oil has been great with drilling and turning and tapping and gives extended tool life.ground stock is a must if you want to hold tolerances. it also has to be ground if u dont want the machine to lock up cause it cant get the bar thru the guide bushing.material cant be bowed or bent either.one thing to remeber is that whatever runout u have in the bar stock you will see it in the finished part.

[dookie2022]

All I can say is that all other machine tool companies copy Star and Citizen machines so why buy copies when you can get the originals.

[abgoel]

We are using them for cannulated bone screw application. I have heard mixed opinion about Citizen and some customers have shifted to Hanwha from Citizen because they were more complex and did not deliver features as promised.

I am waiting on Tsugami application and also Tornos as well.

In the end, we evaluate on

1. repeatability,

2. surface finish,

3. productivity,

4. deep thread cutting

5. Deep bore drilling upto 100mm (and preferably 120mm)

Diameter in the range of 12-14mm.

[DCogswell]

Tsugami S206 needs to be on your short list of machine models to look at. It will do thread whirling & 100mm drilling. I'm sure if you need to get to 120mm, you can make a custom holder to get the extra 20mm.

In regards to repeatability, you can strike Tornos off your list, they have a horrible reputation for thermal expansion. I know all machines experience thermal expansion but, their's is wickedly unpredictable and can be very frustrating for your operators.

For surface finish, beyond the obvious, (material-Guide bush-tooling-F&S-, etc.) you need rigidity. Rigidity comes from weight, spindle/GB bearings and casting design.

Comparing iron casting designs, the Tsugami S206 is far superior compared to the L20 & SR20. The S206 casting is the length and depth of the machine. Compare that with both the L20 & SR20 which the casting is only under the main spindle. Also, the S206 is about 50% heavier which adds to better rigidity & surface finish.

my .02

[hacdlux]

i'll second dave

my ss32 has had parts run .00005 across a run if the temperatures in the shop stay consistant (winter) even in the summer when we have a 40 degree swing it will only change .0004 and thats on the sub which is affected more

[ProProcess]

... The S206 casting is the length and depth of the machine. Compare that with both the L20 ... which the casting is only under the main spindle....

The L20's casting is not just under the main spindle, see attached

[SirDenisNayland]

Compare that with both the L20 & SR20 which the casting is only under the main spindle.

This has got to be the most ridiculous statement I have ever heard. What do the sub spindles ride on then? The sheet metal enclosure?

:banana:

You are right though in your statement about weight: the more weight the more grounded the machine is and the less susceptible to vibration leading to inconsistencies. Rapid movements on the sub can really affect your main. I am of the opinion though that unless your machine is a feather weight, most of your diametrical inconsistencies can be solved with proper tooling, setup, and material.

That being said, I'll hold .0001" all day any day on any swiss machine you throw at me. Everyone speaks like this is some sort of "holy grail" achievement.

[DCogswell]

This has got to be the most ridiculous statement I have ever heard. What do the sub spindles ride on then? The sheet metal enclosure?

:banana:

You are right though in your statement about weight: the more weight the more grounded the machine is and the less susceptible to vibration leading to inconsistencies. Rapid movements on the sub can really affect your main. I am of the opinion though that unless your machine is a feather weight, most of your diametrical inconsistencies can be solved with proper tooling, setup, and material.

That being said, I'll hold .0001" all day any day on any swiss machine you throw at me. Everyone speaks like this is some sort of "holy grail" achievement.

For "at limit" machining, weight and effective casting design are imperative to reduce the harmonics created while machining. Combine those attributes with spindle design, spindle chiller and direct drive RGB you have a very robust platform to tackle your most difficult applications.

The SR20's and L20's are highly evolved platforms that compete very well in the marketplace however, when someone is looking for the best in the industry, Tsugami has features that make their machines stand out.

In comparing the casting designs, the Tsugami has a casting that is the full width and length of the machine. The spindles reside within the periphery of the casting. As opposed to the L20 where there is an extension to the sub-spindle. And for the SR20, the sub-spindle base is bolted to the main casting.

And, BTW, God on a Christmas morning Sunday couldn't hold .0001" on a Deco 16. I don't care if your set-up is perfect and your material is perfectly ground and straight. It's just not going to happen throughout a production run.

Happy Machining.

[ProProcess]

...And, BTW, God on a Christmas morning Sunday couldn't hold .0001" on a Deco 16. ...

Now that's funny!

[SirDenisNayland]

Indeed funny.

Certainly offset adjustments are always necessary (I dont care who or what your situation is, much like you said), but I truly believe you should be able to hold .0001 roundness and concentricity off the main without any real issue, perhaps god on christmas sunday morning cant, but I can. The sub is where you get into problems blending the two, and that goes for ANY machine and comes down more than anything to your pickoff collet, and if the machine has been crashed or not.. because we all know they're never the same once that happens

I've heard many a bad thing about tsugami, from their spindles to their way designs, but I have yet to run one of my own so I will take your word for it, as we cannot always believe hearsay.

Cheers

[DCogswell]

Again, we're talking "at limit" machining. The SR20's & L20's are high-end swiss-type machines that can handle nearly anything you can dream up. However, I've also experienced circumstances where the Tsugami made a difference and allowed the customer greater sense of confidence that the process was repeatable across their production environment.

Remember, not all shop floors are equal and not every decision maker has the same options. In my current role, my focus is being able to create a process that can be repeated, with minimal guidance and perform that function in a timely manner.

Also, on my shop floor, I have 2 Citizens, 6 Stars and 4 Tsugami's. Two of the Tsugami's are NP-11's (early 90's machines) that run 24/7 with auto loaders. I've personally never seen a main or sub-spindle replaced on any Tsugami.

I would have no trouble buying another SR20 or L20, as long as that machine fit within our objective.

Happy Machining!