Swiss Type Machine: Can they make square shafts?

I have a production part I need to increase sizes and speed on. The parts are roughed on a 4 axis lathe with live tool currently. Part is 5/16 diameter O1 bar stock, milled to a 1/4 x 1/4 square shank 2.55" long and parted. That leaves original 5/16 diameter corners for smooth edges. I need to make 5/16, 3/18 and 1/2 soon and need to get the daily run time down from it's current 18 hours to make 400 parts.

"But why don't you..."

Do them on the mill: Labor cost is enormous to have someone standing and loading them 1/3 of each day
Buy square stock: because no one makes it. Only precision flat ground and it costs 5x more

Can a Swiss Type lathe such as a Cubic SD16 or Hardinge ST-220 make these? It would need to feed while side milling 4 sides and retract after three of them.

Would the bushing hang up on the bur from the first, second and third size making it a non-starter?
Do the milling spindles on these things have the balls (bearings) to side mill .032" DOC all day long?
Are the tool position offsets fixed or can you use tool ## offcenter to side mill as it is fed or can you only feed dead nuts on the tool line using the tip of the EM rather than the side?

I run these on a axial live tool so the tips of the EMs constantly chip even with a live center supporting the end of the bar. The feed-n-cut style seems like it would save me the time to center drill, pull, move center etc. Bonus.... HUGE bonus would be the $4,000 worth of chipped tipped EMs I have would go from scrap to gold since I could use them on their sides.

I think there is enough of the original OD to provide support but having never seen a swiss much less run one I'm not sure. Finish is unimportant as the parts tumble for 6 hours after but size is +/-0.0007

Are the "smooth corners" left over from machining 1/4" down to 5/16" a requirement, or just for a nice finish? What about keystock? Could you part off keystock and load it in a tumbler?

Smooth corners are a requirement. I'm not aware of O1 keystock, but I would imagine it is ground and cost would be much greater than my cost per foot currently. If anyone on earth made 1/4 x 1/4 extruded O1 I would use it. They don't unfortunately. I definitely could tumble the corners off cheaper than machining the flats.

I am not interested in changing from O1. Far too much time and money invested in the learning mistakes of heat treating these parts. By the time I find out there is an issue there are $20K worth of parts out in the wild.

The remaining diameter of the 5/16" bar stock is plenty to support in the guide bushing.

You may consider tipping the part and deburring the edge with the end mill as you retract or switch to a chamfer tool and deburr as you retract, I do both on parts I make.

The larger max OD machine, the more guts the live tools will have. I would recommend at least a 20mm machine with ER16 live tools over a 16mm or smaller swiss.

A Citizen A20 would be a good candidate for this, I have one, but I am rarely work where cycle time is critical.

Citizen A2�-VII Demo - YouTube

You have full Y axis control over the centerline of the live tools, can plane switch as well and circular interpolate.

danrudolph said:

The remaining diameter of the 5/16" bar stock is plenty to support in the guide bushing.

You may consider tipping the part and deburring the edge with the end mill as you retract or switch to a chamfer tool and deburr as you retract, I do both on parts I make.

The larger max OD machine, the more guts the live tools will have. I would recommend at least a 20mm machine with ER16 live tools over a 16mm or smaller swiss.

A Citizen A20 would be a good candidate for this, I have one, but I am rarely work where cycle time is critical.

Citizen A2�-VII Demo - YouTube

You have full Y axis control over the centerline of the live tools, can plane switch as well and circular interpolate.

Click to expand...

Phenomenal video! I've been looking at them for days and that showed more than everything I've found combined for what I'm looking at.

Tipping and light chamfer would work perfectly as it's retracting anyways I could do it with the same tool in a snap. I'd love to find a good deal on a 20mm. Most of the ones I'm seeing are 16 unfortunately. I have $50K all in aside for the used rig. My $15K 22 year old Miyano has knocked out 44,000 of these in the last year but the tool bearings and chipped EM cost are killing me. Not to mention I NEED a bar feeder to be able to run a few hundred lights out. The 18 hour days are starting to get a bit old. Just picked up a third mill for these just to do the engraving, and a 4th will come later this year, but I have to be able to feed it and right now I couldn't do it with the Miyano.

Here's a video I made showing the basics of the Citizen's I have.

Swiss Explainer - YouTube

If you look for a A20 Type 6, it would be significantly cheaper due to the sub not having an independent back working block. Most of them have out there have been ridden hard and put away wet.

Too bad your tolerance is so tight, otherwise it seems like a good application for polygon turning.

I agree with dan...20mm machine, ER16 cross live tooling, magazine bar feed and your life will be sooooo much better! the corners you're leaving will be fine on the guide bushing land. ummmm, you should be able to do whatever engraving you're doing in the mill in your new swiss, too....BOOM! Also, you'll probably be much more rigid working right up against the guide bushing than in your current fixed headstock machine even with the live center, so there's benefits to be had there, too. You could use an indexible em so you're just flipping inserts instead of throwing the entire cutter away but you'd have to do the math to determine what's better. In my Tsugami I use a 3/4" two flute indexible Iscar mill to cut 1/2" rd 4340 down to 3/8" sq (so leaving round corners like you do) about 2" long and get maybe 1,000 pcs per side. $50k should get you something you can get the job done with. Good luck!

Vancbiker said:

Too bad your tolerance is so tight, otherwise it seems like a good application for polygon turning.

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I was thinking "thread whirling" when I read the description, too.

It's worth a look .....

Vancbiker's polygon turning idea sounds interesting. The 1/4" square is just the handle of the punch, right?

Alternatively, have you looked at getting them cold drawn to net or near-net and replace the entire roughing op with an auto-saw? I looked at getting some material custom cold drawn and it was surprisingly reasonable. That was in small quantity, I imagine in the larger quantities you're dealing with it would make a lot of sense.

SeaMoss said:

I was thinking "thread whirling" when I read the description, too.

It's worth a look .....

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Thread whirling and polygon turning are very different animals. Unless you're making a joke I'm not picking up on, because your posts are usually so spot on that I doubt myself for doubting you.

danrudolph said:

Here's a video I made showing the basics of the Citizen's I have.

Swiss Explainer - YouTube

If you look for a A20 Type 6, it would be significantly cheaper due to the sub not having an independent back working block. Most of them have out there have been ridden hard and put away wet.

Click to expand...

I have been looking for only a month and it seems like slim pickins so far. Today I talked to the owner of a Hardinge ST-220 - 0.75" Bar, 8,000 RPM, yr 2000 with low hours. It hasn't been parked (allegedly) but in a job shop where they rarely have the right work for it. It's 20 mins away so I'm going Monday. The dealer mediary offered me a $$$ warranty to repair or replace anything since it's not under power (replaced by chucker 2 months ago). BEST PART is it has a 12' LNS Hydrobar express all for $33K. Not sure how many 55 gallon cans of lube it's gonna take to fit her in the shop but I'll figure it out.

Vancbiker said:

Too bad your tolerance is so tight, otherwise it seems like a good application for polygon turning.

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That's a new one to me. Just looked it up. WOW. I am sure there are other set ups but it would seem like the part would deflect but likely in a predictable and could be corrected for like I do now. The spring type live centers from royal aren't as rigid static and spinning unfortunately.

Nerdlinger said:

I agree with dan...20mm machine, ER16 cross live tooling, magazine bar feed and your life will be sooooo much better! the corners you're leaving will be fine on the guide bushing land. ummmm, you should be able to do whatever engraving you're doing in the mill in your new swiss, too....BOOM! Also, you'll probably be much more rigid working right up against the guide bushing than in your current fixed headstock machine even with the live center, so there's benefits to be had there, too. You could use an indexible em so you're just flipping inserts instead of throwing the entire cutter away but you'd have to do the math to determine what's better. In my Tsugami I use a 3/4" two flute indexible Iscar mill to cut 1/2" rd 4340 down to 3/8" sq (so leaving round corners like you do) about 2" long and get maybe 1,000 pcs per side. $50k should get you something you can get the job done with. Good luck!

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That's a hell of an idea to engrave them on the lathe. This thing should be able to run 2-5x the stamps I can machine per day even after the 27K RPM Speedio makes it way into the shop... and it ran the SAME code that ran on my Haas OM2A today in 1/3 the time. 1/3. No BS. It was the PERFECT part to see what the max difference could be though. Can't wait to post some pics of those running side by side.

DanielG said:

Vancbiker's polygon turning idea sounds interesting. The 1/4" square is just the handle of the punch, right?

Alternatively, have you looked at getting them cold drawn to net or near-net and replace the entire roughing op with an auto-saw? I looked at getting some material custom cold drawn and it was surprisingly reasonable. That was in small quantity, I imagine in the larger quantities you're dealing with it would make a lot of sense.

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The whole shank is 1/4. The letters/designs are currently all 5.5mm or smaller. The customers are impatiently standing in a VERY long line for me to offer 5/16, 3/8 and 1/2 shank options with larger designs and some monogram fonts. Right now I can't justify the change over time since I can only load the lathe 17 hour a day. Looking forward to sub 100 hour weeks.

I never actually priced out having the O1 cold drawn. That really would work for sure. Heck I could grind them all a hair if needed with minimal labor and operating cost. For now I'm LOVING the idea of the Swiss now that I watched the above video. I have a few other parts that I make that I could do MUCH easier on there too.

TeachMePlease said:

Thread whirling and polygon turning are very different animals.

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You're right ! But once upon a time I was looking into a way to make worms and coulda swore someone was doing non-round shapes by whirling ? They timed the cutter to the part and had oddly-spaced different-shape cutters in the holder ?

Can't find anything on that now tho. Was that a failure or did my brain just invent this ?

There is skiving tho, it might work :

Power Skiving Unit

Fellows used to make all kinds of strange cutters for doing non-round shapes by generating.

You know ... I'm suddenly thinking a 610 Barber-Colman could kick ass on this part and be very easy even for untrained people to run. And way less expensive than milliing ... although you couldn't multi-op it. Still, making the squared blanks would be very automated and the machine is much cheaper than a Swiss.

They make machines like this



with autoload, only a little smaller. Get a mechanical one instead of cnc and that thing will run forever at low cost, and probably as fast or faster than live milling on a swiss.

You couldn't engrave on it tho

For that size and tolerance I'd investigate a cnc tool and cutter grinder. The barber coleman may be a good bet too. Can you buy O1 precision flat ground in (your size) square, chuck it in a square collet and just knock the corners off a little?

PriddyShiddy said:

I never actually priced out having the O1 cold drawn. That really would work for sure. Heck I could grind them all a hair if needed with minimal labor and operating cost.

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The other nice thing about cold drawing is that you save ~19% on material. The bar gets longer instead of having material turned into chips. This could be a nice savings.

PM sent with a few details on my experience.

If you do go the cold drawn route, this is the exact part sizes - shapes that makes robotic load and unload as near effortless as it comes. Hell you could turn your current 17 hours production into 24 and do that whilst say only visiting the shop for a couple of hours early morning and then the same again later in the day to reload - recheck stuff once you get it running. Yeah upfront you have some machine costs, but if your products good, its all gravy down the road.

Whats more once you have these kinda parts running near fully automated your free to do other stuff develop other avenues.

Getting it cold drawn to size should not be all that costly either so long as your buying in quantity. Hell a few hundred or low thousands of lengths per order and i reckon they will even radius the corners for not much more.

WILLEO6709 said:

For that size and tolerance I'd investigate a cnc tool and cutter grinder. The barber coleman may be a good bet too. Can you buy O1 precision flat ground in (your size) square, chuck it in a square collet and just knock the corners off a little?

Click to expand...

The tolerance is easily acheived with my 22 year old Miyano, but the live tools suck and the surface it terrible. Doesn't matter after tumbling, but the swiss means no tumbling. No second op to cut off the left over material for the live center and chamfer, and I could engrave my logo and USA on every stamp. I'd still need to engrave the PN, Date code, name of font/design and letter etc, but it would save the engraver time for sure.

The PRECISION in precision flat ground is a HUGE problem. At 5,000 parts most months and $1.10 more per part cost that would pay for a new Citizen payment, another shop to put it in and a few cases of beer to drink while watching it work

Definitely going to look into the cold drawn. Never even considered it before.

Are they just taking existing round bar and drawing it? So it's current cost of bar (minus whatever volume discount I can get), plus die, plus drawing cost?

Regarding automation these are pretty darn automated on the machining side. Right now I load 114 blanks in the OM2A and it runs for 4-30 hours depending on the parts. If I can free up the TM2P from doing the supplemental machining I have to do I can make a fixture to engrave a few hundred parts at once or buy a gantry style fiber laser.

Brother just did a test for me on the 30 hour parts with their 27K spindle s500 and because there are a ridiculous amount of rapids and direction changes the Brother would do the same thing in 9 hours. I know it sounds like bull, but there are literally thousands of .075" rapids per part and tens of thousands of direction changes and the brother handles those 3-4 times faster than the Haas can. For the bulk of my work it would only save 20% but I firmly believe i'll see better tool life over the OM2A's little toy spindle. The OM2A spindle is practically the size of the live tool spindles on my Miyano and if I run it at the claimed 30K rpm it shreds a belt every 300 hours requiring a 3 hour tear down.

With the bigger table on the brother I would just set up Pierson pallets and could load 24 hours worth of parts switching tools with every xxx parts and load once per day with fresh pallets loaded offline while making 3 days of current production.

Why are you cnc engraving in production that high? a little stamping press and a die set could do in less than a second what it takes minutes for a cnc mill to do. Just have to have steel stamps aligned with the part.

even if its serialized its stampable.