A lathe upgrade or just a silly idea?

[jwmay]

After an exhaustive search of my personal hard drive, I decided that it would be unnecessary for me. So if you have a 300 pound lathe made in 1940 or thereabouts, mounted on a wobbly tool box and not bolted down, I wouldn’t bother. But like I said, that’s just me. Even with all the obvious things I never did right fixed, a regular old drive pulley that wasn’t bent would probably help me out tremendously. Then again, we all have different performance expectations, and what I’ve got works fine for me….sorta.

 

[Ultradog MN]

I'm not quite sure if you've talked yourself into a better lathe or talked yourself out of one.
But I will say this:
If you have a lathe and want a better one consider that you already have a leg up in that you can sell the one you have - either before or after you get the better one - and you probably have some tools and tooling that you can keep to use on the next one.
So the cost of getting into a better machine won't be so exorbitant.

 

[jwmay]

I'm not quite sure if you've talked yourself into a better lathe or talked yourself out of one.
But I will say this:
If you have a lathe and want a better one consider that you already have a leg up in that you can sell the one you have - either before or after you get the better one - and you probably have some tools and tooling that you can keep to use on the next one.
So the cost of getting into a better machine won't be so exorbitant.

Lol! I think you might be talking to me, and I’m not the OP here. I was just saying there’s a host of reasons my machine wobbles, and a damper ain’t the answer.

 

[Ultradog MN]

Lol! I think you might be talking to me, and I’m not the OP here. I was just saying there’s a host of reasons my machine wobbles, and a damper ain’t the answer.

My bad.
I didn't realize you were replying to another thread.

 

[Steuss Moore]

Damn, this is a load of answers... And some things said that neither resemble an answer to my original post nor seem to allude that the person who wrote them read the original post...
I`ll shoot down the benmy first... I am not in problem, nor in search for a solution... I was merely looking and some things, and the idea of applying the fluid harmonic damper to a lathe came to mind... I aint searching for anything, i was just contemplating possible applications of known tech to known tech that could benefit therefrom...

To pontiac, again, its not really a question of solving a problem of any kind, its a theoretical application of a piece of engineering to a machine that could benefit from it... Im not having issues with a lathe in any way, im just considering tinkering... Also, i hardly doubt that a 3 ton lathe is in dire need of epoxy enhancement... No doubt it could be applied and used to some effect, but the 3 tonnes of cast iron kinda render that a moot attempt... Kinda like tossing a molotov out of the bomber after you already released the nuke... Also, im talking fluid filled harmonic damper, not rubber, which are extremely broad in their range of harmonic coverage, so changes in mass or speed wont really affect the effectiveness of the damper... Rubber ones are limited as hell in their range of coverage, but fluid ones are a marvel of engineering practically... And the torsion i was mostly considering is the imperceivable vibrations of the actual cutter engagement, as it is like everything, elastic... I know im talking micro movements, but that **** travels through the spindle shaft and acts like a source of harmonics... Something that the damper should alleviate a bit, dont you think?

Fomogo, the lathe is a beast with special in house IWK motor made and balanced to essentially run a surface grinder spindle, but its an 11hp 3phase motor for a lathe... A beast, yet a refined one... The pulleys and everything is balanced and essentially made to grinder specifications... Its the old german make, and she really embodies the stereotype of ``german quality`` back from the good old days...(dont quote me on the specific time of the good old days, as that is a landmine of a topic)

Jan, as said, yeah, she is a 3phase beast, 11hp, special design motor by the oem... The lathe is Schaerer UN450... You can find one i think on one of the forums, was used as a polishing lathe... A few pictures should be on that thread... Otherwise a very rare lathe from what i can see or find... In last 5 years, i have seen 2 online and i own one... There are more modern Schaerer UD variants, which are less rare, but the UN variant seems to date back to before the 50`s... I cant really find **** either on the Schaerer IWK as a company... I have seen a manual page marked as 1992 from them, so they should have existed until recently, but i cant really find much on them, or anything for that matter really... Only Schaerer i can find is the coffee machine specialist mfg...

As said, im not really asking for a solution, nor dealing with mystery source chatter or anything, the original post was merely a mental gymnastics exercise into application of what seems like a viable upgrade... I know its more of a wild goose chase and an application better suited for other things, as grinders and similar circumvent that issue with other means, but i stated that in the original post anyways... Its just a question and an idea that i had wanted to present to fellow machine minded individuals here... I said i am not looking for anything major with the idea...

Mark, you seem to get the notion... Yeah, its literally what i wanted to talk about... What do you guys think, would the damper impart even the most minute changes for the better, even if we are talking ridiculous parts with ridiculous demands on finish and other factors... I am not in need of bettering my big lathe, it was merely an invitation to contemplation about its potential gains or detriments...
Now if anyone wants to talk other ideas, upgrades, ways of bettering a machine, im open to it, Jwmay, that what you described sounds more like a hazard really... Wobbly lathe? Yikes! Get her some love and proper mounting surface... Go to the scrappers, get a 200kg slab of steel, you can always find industry junk, thermal plates from massive heating systems that are 4in thick and massive af... Bolt that poor girl down to a slab`o`steel, scrape her in, do the hokey pokey, you know the drill... Any machine can be made to operate to an extremely high standard... The damper is just my wild idea regarding micro effects in the surface finish, tool life and maybe bearing life... And i know that a 300lbs lathe aint a 3 ton lathe, but she can be helped and nudged into being a great performer... I have a baby lathe, 150lbs, bolted to a rickety table, so i know what you are talking about there, i really have to make her a proper stand, i got her with the bench... But i do have a slab of steel to mount her to... I advise you to find a slab yourself and do what you are willing to do, be it just bolting her down, or full scrape job on the lathe feet and the mounting surface of the slab as to both level the lathe and assure max contact surface for clamping... If a bed is gentle, bolting it down properly to a good surface will render it much stiffer... Also that in conjunction with epoxy granite is a surefire way to make a proper little monster of a lathe, just be careful not to induce warping with improper bolting down or other silly nonsense... 300lbs should be in the handling range of a single man, at least given that the lathe aint a solid 300lbs slab, but a system of pieces that can be taken off...

All the best people and thanks for the input!

 

[jwmay]

Well ok. I don’t think there’s any value in the mental effort required to build a vibration dampening pulley. Not silly, but not an upgrade.
Also if I wanted to deal with rigging and moving giant slabs of steel in order to make my lathe more sturdy, I may as well just buy a heavier lathe. Lol
I’m working on it though.

 

[jwmelvin]

[mention]Steuss Moore [/mention] I think it’s a neat exercise and it would be interesting to see the effect. I believe the first practical thing I machined was during my first summer in engineering school working for a grad student; he made a harmonic damper for cable-towed ocean devices, and it worked wonderfully well. This was much lower frequency, fairly large-amplitude motion. It used two cylinders rotating with viscous silicone fluid between them.

Sounds like the approach you describe would be fairly similar, just using an inertial ring as the sink. I’d think tool-induced vibration is pretty high frequency, so reaching the spindle damper through torsional flexing modes? Motor vibrations seem broadly relevant, so there must be some work in this area for motor dampers?

 

[rabler]

I'm thinking of general vibration/chatter, not specific sources like from a pulley. I'm no expert, but I suspect one problem would be that a lathe can vary widely in both RPM and mass of the workpiece. I think that would make tuning the mass damper, even a fluid-based one, a challenge. Add to that, ideally the damping system is mounted close to the source of oscillations, which in a lathe is at the cutter. Anything added in that area risks complicating the operation of the machine.

 

[matthewsx]

I had similar dynamic balancers for sale when I had my kart engine business, never found much use or market for them.

For the most part vibration when machining is easily dealt with by tool choice and feeds/speeds.

While some on here might welcome this mental exercise, others are much more practical minded.

What we try not to do here is denigrate anyone for their questions, or answers to whatever is posted.

When members with decades of professional experience say that whatever idea is being discussed is probably not going to bear fruit it’s usually good to acknowledge what they say.

If you’re not getting the desired answers it may be that the question isn’t well framed or the discussion is not fruitful.

JMHO,

John

 

[Steuss Moore]

I had similar dynamic balancers for sale when I had my kart engine business, never found much use or market for them.

For the most part vibration when machining is easily dealt with by tool choice and feeds/speeds.

While some on here might welcome this mental exercise, others are much more practical minded.

What we try not to do here is denigrate anyone for their questions, or answers to whatever is posted.

When members with decades of professional experience say that whatever idea is being discussed is probably not going to bear fruit it’s usually good to acknowledge what they say.

If you’re not getting the desired answers it may be that the question isn’t well framed or the discussion is not fruitful.

JMHO,

John

John, i get what you are saying and appreciate the input, but as i said, this wasnt really meant to be a discussion on efficacy of the concept, as i said in the o.p. -the effects may be minimal, i am just presenting an idea that came to mind for general review and contemplation... I even invited whatever opinions, but i wanted them to be posted with insight into the arguments for it, not just a blanket statement of its dreck...
I merely proposed the possible effects and how it could positively effect the machine and the parts produced... Im well aware of general machining methods and approaches to tasks at hand, but i dont really see any of the traditional methods of contending with finish to be effective in regards to natural oscillations that are a result of using any motor really, other than the hydr. damper which would, as said, i assume be able to mitigate some of those effects of motor drive, especially in conjunction with a belt drive... I didnt really ask personally for advice, is what im trying to say, i was just wanting to open a discussion for people with greater experience than mine to offer their wisdom in general - regarding the idea... Kinda like jwmelvin offered... I ask for nothing concrete, but if anyone offers that, great... I didnt spit on anyone in the second post, or at least i dont think i did... I just said what i`m saying now... I think i acknowledged most people, i didnt say that they are idiots for their arguments, i merely said that they kinda missed the mark, again, as i was not asking the questions they were answering...
The discussion wasnt a total fiasco, on the contrary, and there are no real desired answers, which is my point, i just wanted to open a grounds for discussing a topic... And in advance acknowledged that the concept could have absolutely minimal visible effects and be merely a silly idea from practical standpoint... I even compounded that in the later part of the o.p. so dont get me wrong, im not denouncing any comments given, i just wanted to let the guys whom i replied to that i wasnt asking from the perspective of someone with lathe issues or problems that i seek to resolve in my specific case... Its a theoretical experiment and mental investigation of a concept that is well proven in other fields and offers great benefits to mechanical systems in general, especially those where a rotary input is being resisted by some factor that is natural to the workings of the system, as is the case with a crankshaft trying to belt drive a ****load of pulleys with varying aggregates offering resistance... The same thing happens with the lathe, you have a shaft, transmitting micro impulses from the motor, into the spindle which while the piece is engaged with the tool, offers resistance to the micro impulses, which in turn, technically twists the spindle shaft on a micro scale... Those twisting forces, i assume, result in some interesting effects on the bearing wear over time... That is what i wanted to discuss, not how to deal with chatter and general lathe related issues that we all know of...

All the best and kind regards