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Has anyone here had time on a twin turret, twin spindle lathe?

I've been programming twin spindles for 20+ years...all with at least two turrets. Index G-200, Okuma LT-15, LT-200. LT-300, Nakamura WTW-150 (Twin Spindle, 4 turret), Nakamura WT-300, Nakamura NTY3 (Twin Spindle, 3 turret).

We have recently been using LNS Quick-6 feeders. Have also used LNS SL (4-5' length feeders). I prefer to stay away from 12' loaders with larger stock because of vibration (running lots of hex stock).

This may ruffle some feathers, but I do not use CAM. I program all by hand....just me, my Casio, and a circle template (BradCam version 1.0). If I was in a job shop, then I'd be using CAM. But, I work for an OEM and the parts are part of families that range in size. It works for me and I think I get to know the machine's capabilities better this way (just my opinion). I get a kick out of watching the younger programmers that use CAM, working on an issue at the machine with the machine operator. They have to go back to their desk and edit the tool paths on CAM, post a new code, and re-download to the machine....about 10-20 minutes before they get the operator going again. For me, I just pull out my calculator and edit the code right there and the machine is back up and going in minutes. I also get a lot of thanks from operators and setup persons on the simplicity of my programs compared to those that are made from CAM.
I'm not advocating for anyone to do it this way, just saying it can and does work, and that CAM isn't absolutely necessary just because there are multiple turrets/spindles.
 
I also do not use CAM. Been programming twin spindle and twin or triple turret lathes for 26 years. For high volume you will never get a better cycle time than with a manually coded program from an experienced programmer. All of my programs also are able to make a whole family of parts.
 
I see a lot of people using constant surface speed on barfeed lathes for no reason. In most cases it can increase cycle times and at the very least is wears out your bearings and spindle drive. Find a nice rpm and leave it at that. If you are turning a shoulder from 2" diameter down to 1-5/8 you dont need to be adjusting your rpms, especially when running a 12' bar.
 
This may ruffle some feathers, but I do not use CAM. I program all by hand....j
I also do not use CAM.

[Almost the] same here.

I use CAM, but every last one of my programs is heavily edited by hand. CAM just reduces the bandwidth required on the old noggin.

My edits involve a lot of cutting and pasting from existing programs, so I'm hardly starting from a blank slate. There's a lot going on in my production programs... macros, dwells, subs pulling parts out, subs pushing parts back in, barfeeders pushing bars, parting off remnants multiple times (to prevent conveyor jams) and a lot of handcoded G00/G01 moves to avoid collisions with the part and subspindle.
 
[Almost the] same here.

I use CAM, but every last one of my programs is heavily edited by hand. CAM just reduces the bandwidth required on the old noggin.

My edits involve a lot of cutting and pasting from existing programs, so I'm hardly starting from a blank slate. There's a lot going on in my production programs... macros, dwells, subs pulling parts out, subs pushing parts back in, barfeeders pushing bars, parting off remnants multiple times (to prevent conveyor jams) and a lot of handcoded G00/G01 moves to avoid collisions with the part and subspindle.
Same. This is where I am at. I have been trying to find a solution for lathe CAM to 'try' to get all programming done in CAM, but it really sounds like that is not practical.

For me, I get my core tool paths out of CAM, then splay out the program at the desk top and get to chopping. Bar pulls and such are by hand. I still don't understand why CAM won't evolve to such simple tasks. I guess we probably all have those quirky things in lathes to get the job done. I know I was cutting off some small stainless pins that were 4" long and they kept pinching my cutoff insert and killing it so I made a little 'thing' out of Al sheet to make contact with the pin during cut off and prevent the pinching.
 
I've been programming twin spindles for 20+ years...all with at least two turrets.

This may ruffle some feathers, but I do not use CAM. I program all by hand...
Another one that doesn't either. It was hard to figure out initially (there wasn't much help available 15 years ago) but I think programs run faster and are easier to edit, at least for me. We do some high production and saving even 3 seconds per cycle multiplied by 100,000 parts adds up.
 
I have had a twin/twin for 20 yrs.
That is a lot of machine to bankroll for a job shop, but I bought it a few yrs old - stripped, and I added tools as the jobs required.

I remember the first time I saw an ad for these, and my mind went :eek:
Knowing the limitations of a M/S machine, and then seeing these come out!
I could think up all kinds of set-ups that I could doo, and things that I just couldn't doo on a single turret sub-spindle machine, and knowing right away how this new gizmo would be able to work around those situations!

I program with pencil cam as well.
I don't find it difficult at all.

One thing about twins, is that you may be limited to tool length on T1/S1 and T2/S2, but long drills go in T2 and work on S1. I have parts that we drill 8.25" through - from one side.

I have had up to at least 12 live tools and I think 32 different tools/supports in use on one job. (carriers)

But they are good for simpler jobs as well as you have less tools to reload, as with 24 tool pockets (or whatnot) it's like Prego, "it's already in there".


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Think Snow Eh!
Ox
 
One other perk for [at least our] twin/twin is that we can run full bore parts (65mm) all the way through ours.
Like today - we are running 20' long pipe in one end, and taking 40" long parts out the other end.

We have a gripper/conveyor on ours, but I seldom ever use it. Takes time and ... it's not exactly the cats pajama's.
But sometimes it's the best option.

If the parts will stack/pack, we run them out through the [sub] spindle - with appropriate sized liner.
It could be a cpl hours before you have parts coming out the other side if you are running shorter/fancier parts.
Otherwise I just drop'm in the chip conveyor.

You would not need to have a twin/twin to be able to doo this, but you doo need a sub with a hollow closer on it, and then the infrastructure to mount your liners and whatnot. (or make it up)


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Think Snow Eh!
Ox
 
Now the "cons".

Maintenance!
You will need a min of 3x the maint on the lower turret than you will the upper.
Everything is falling into it, as opposed to away from it.

I know my lower turret inside-out and bass-akwards.
Not yet been into my upper, but the day is nigh....

However, per one of the early posts here regarding taking two days to align....
In two days, I can replace the X2 and Z2 rails and have mine re-aligned....


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Think Snow Eh!
Ox
 
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You guys are talking about my idea of fun! I manually programmed from 1985 until 2008 at which time I was told the company wanted all my programs done in MasterCam (which we had had since at least version 6). I love a family of parts. Love Macro B programming. Most of my programs make use of variables. Obviously not done by MasterCam, but added by me later.

My boss said the other lathe programmer was faster than I was using MasterCam. Three things. 1) He was more computer literate, 2) he only used MasterCam to program, and 3) I take the time to modify my Lead Ins/Outs (with a trusty calculator). You won't find any .0008 rapid moves in my MasterCam programs. Nor any .0005 DOCs in my roughing operations. :)

Ox, the most tools I can remember using on a job is 26 on a Doosan TT1800SY. Used all 8 live tools (which is all we have for it). At 71 I learned how to thread mill side ports and how to engrave on this lathe. I really like the results thread milling gives. So much nicer looking than tapping.
 
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Now the "cons".

Maintenance!
You will need a min of 3x the maint on the lower turret than you will the upper.
Everything is falling into it, as opposed to away from it.

I know my lower turret inside-out and bass-akwards.
Not yet been into my upper, but the day is nigh....

However, per one of the early posts here regarding taking two days to align....
In two days, I can replace the X2 and Z2 rails and have mine re-aligned....


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Think Snow Eh!
Ox
Ox, sort of curious about your toy there. Can you share what you run? I think the few machines I have looked at had both Turrets up top. Probably some pros and cons. I can see those two conflicting a bit when you have tooling loaded. I am notorious for leaving tooling long to hang out the back because I never know when I will "need another 2""..... But that could be bad news in a twin.
 
Mine is a Hardinge Twin Turn.
They have not made those in several years now.

Double uppers would be advantageous for the porpoise of keeping them out of the Shiite, but that layout would not lend it'self well to jobber work IM/HO.


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Think Snow Eh!
Ox
 
Hi, Does anyone have any tips or guidance on how close to run the 2 heads in Z when turning an OD as quickly as possible?
For example, this would be a 2mm offset.
H1 G00X70.0 - H2 G00X68.5
H1 G00Z1.0 - H2 G00Z3.0
H1 G01Z-100.0F0.3 - H2 G01Z-100.0F0.3
Would a greater or smaller offset be better and if so why?
 
Doosan (now DN) is South Korean. They mostly use Fanuc controls.
When you get to this complexity of machine, it's going to take a lot more than an extra $20k to get you from a Doosan to a Mori. More like $200k... Maybe that's an exaggeration... but maybe not.
Also, consider Miyano single turret, sub-spindle machines. Some of them have an X-axis on the sub that allows it to follow the turret so that a single turret can cut on both spindles at the same time. It saves on cost and floor space. I don't have experience with them, so I can't tell you what drawbacks that design might have.
The machine from Miyano that does this is the BNX51msy. We have two and they are really good machines. If you do a lot of milling and OD drilling than you may want to look at an actual twin turret machine like the BNE. But if you do more turning than milling the BNX is great. The superimposition and X2 sub spindle is awesome.
 
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The machine from Miayno that does this is the BNX51msy. We have two and they are really good machines. If you do a lot of milling and OD drilling than you may want to look at a actual twin turret machine like the BNE. But if you do more turning than milling the BNX is great. The superimposition and X2 sub spindle is awesome.

What kind of volumes doo you run on these?


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Think Snow Eh!
Ox
 
What kind of volumes doo you run on these?


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Think Snow Eh!
Ox
We run a big part family on these machines. The parts have no live tool needs, just tight tolerance turning, drilling, and boring. we do 5000 pcs per month, per machine. Two shifts. The material is a high chrome cast iron. The machines do well considering OD turned tolerance of -+ .00025.
 
We run a big part family on these machines. The parts have no live tool needs, just tight tolerance turning, drilling, and boring. we do 5000 pcs per month, per machine. Two shifts. The material is a high chrome cast iron. The machines do well considering OD turned tolerance of -+ .00025.
Whats cool is we are turning the OD of both parts (main and Sub) Simultaneously. Drilling both parts. And boring both parts using the X2 superimposition. With one turret!
 
That was my guess. Dedicated to continuous run.
You have a part family that lends it'self well to the layout.
And you have taken the time to lay out the code / process to exploit that as well.

I run a twin turret for job shop qtys - 500 - 5000...
I would not expect your machine to rarely ever be anything more than a single turret lathe on most any work like that.


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Think Snow Eh!
Ox
 
That was my guess. Dedicated to continuous run.
You have a part family that lends it'self well to the layout.
And you have taken the time to lay out the code / process to exploit that as well.

I run a twin turret for job shop qtys - 500 - 5000...
I would not expect your machine to rarely ever be anything more than a single turret lathe on most any work like that.


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Think Snow Eh!
Ox
For you OX you would probably like the BNE machine(twin twin). I am also a big Hardinge guy. We have basically every style T42 made from the newest model to the original, and every configuration. Tailstock, sub spindle, Y axis etc. I often compare the machines and ask my self what is the best and why. Its difficult. But for higher volume part families I really like the Miyano. Productivity wise they are very good. The Hardinge I think were more geared towards accuracy and stability. Hardinge does make a twin turn again. I believe its the Talent series. I am not sure how it stands up to yours.
 








 
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