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Why do 70 Year old Machines areas accuarte as they were when built?

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Richard King

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Why do 70 Year old Machines are as accuarte as they were when built?

I have been thinking about this thread for a while. I will ask a few questions to make you think about why? I walk thru shops and see a Sip or a Moore Jig bore or a grinder like the one Ballen had, a Studer that was still accurate after years of use. He was experiencing some stick slip but it was still accurate if your remember. Lets discuss why....why are those 1950 machines still accurate?
 
Alright Mr. King,
I'll be your huckle berry...
Good materials used in construction. Good engineering and a large amount of institutional knowledge of what would work and what wouldn't. Not to mention a good bit of pride.
Another thing that comes to mind ( and this is a bit of an 'intangible') is a mindset that "wanted" to build things that lasted and that would be useful. I write this as I went through business school in the mid eighties and was taught ( quite unsuccessfully I might add ) that anything that was made to last more than one fiscal quarter was 'unprofitable' and thus a waste of time and resources.. But I'll digress lest I rant..
Stay safe
Calvin B Haxton
PS I run old manual machines everyday that have seen better days and have been "run hard" in their past lives and it still amazes me what I can make them do...
 
I have been thinking about this thread for a while. I will ask a few questions to make you think about why? I walk thru shops and see a Sip or a Moore Jig bore or a grinder like the one Ballen had, a Studer that was still accurate after years of use. He was experiencing some stick slip but it was still accurate if your remember. Lets discuss why....why are those 1950 machines still accurate?

Hi Richard,

If you look at the machines you called out (SIP, etc.) These
are not machines that are run back and forth a lot. The Studer
is the exception to that idea, as that's all they do is run back
and forth all day.

I had a world war 2 OD grinder, that had seen a lot of miles but
would hold .0001". This machine was built like a rock. The "V" ways
were 3" on a side (6" of surface), and the ways were lubed on every
traverse. They were hydroplaning on the oil surface an never saw
metal to metal (except maybe for the very first traverse).

If we made all surfaces run hydrostaticaly they would never wear out.

Paul
 
Calvin B hit the nail on the head "amazes me what I can make them do..."It's the craftsman that makes the difference.
Lodge&Davis
 
Calvin B hit the nail on the head "amazes me what I can make them do..."It's the craftsman that makes the difference.
Lodge&Davis

I'll second that. I've used beat up machines, but knew they were beat up going in so adjusted my techniques to match. On the flip side, I have seen people that assume a C-N-C machine will just be perfect every time and they don't need to think about loading a part correctly, or checking dims... :crazy:
 
Maintenance

I have been thinking about this thread for a while. I will ask a few questions to make you think about why? I walk thru shops and see a Sip or a Moore Jig bore or a grinder like the one Ballen had, a Studer that was still accurate after years of use. He was experiencing some stick slip but it was still accurate if your remember. Lets discuss why....why are those 1950 machines still accurate?

Richard

Many other good and valid points have been make. I think maintenance has a lot to do with it. I think 70 years ago people generally took better care of tools than they do now.

CarlBoyd
 
One thing to take into consideration is- if we built machines like those today, they could easily cost hundreds of thousands of dollars. Some of the Euro manual machines still available are a good example- a relatively simple manual mill, built to those standards, today, runs close to $150,000. (New Kunzmann, a deckel like mill).
The last real american built lathes, sold to the Navy in the early 90s, were around 200,000 each for 18x72 ish sized machines.

A new SIP - like machine would probably cost a cool million, in a retro manual configuration.

So the question is not- could we build machines that good today?
Its- would anybody pay for them?

The europeans still do pay a hundred grand for a pretty small manual lathe,
I dont know what the current price would be for a Fehlman Picomax benchtop mill/drill, but I would guess it would be close to a 100k.

Quality costs money.
US companies arent generally willing to pay that much- instead, they buy relatively disposable CNC machines, with an industrial lifespan of 10 years or so, before the electronics are obsolete, but at a much lower cost than a precisely built manual machine would be- and, the added benefit of much more productivity and speed.
 
Maybe because these machine builders tried to build reliable and good machines, in order to do so they did lots of testing to figure out whats gonna work best. They couldnt afford building bad machines. Nowadays there arent lots of machine builders out there, there are not lots of competitors so if you wanna get a machine you either buy a used one or crappy chinese, if you dont wanna spend hell lot of money. Machine builders back then tried different materials as sliding partners, hardened and lapped steel ways riding on superbly scraped 40ppi, heavily casted machine base sitting on three points, different oil grooves etc. etc. I think especially scraping made a huge difference, nowadays machines are built as cheap and as fast as possible, and scraping is really time consuming. They are meant to break down in order to sell a new one. Also lots of knowledge got lost
 
Assuming they got it right in the first place, and its set and adjusted correctly, is it fair to say inaccuracies generally come from wear? I have several 100 year + old watchmaking lathes, the plain bearings are like new. Why? with a perfect enough fit and finish there is no metal to metal contact with a hydrodynamic bearing. I would think it likely that a very high end piece of equipment (i.e. bearing surfaces very flat and smooth) and correctly lubricated could experience the same low wear - its also a hydrodynamic bearing. The higher end it was, the more likely it would to be lubricated properly.

If you read up on tribology, they describe wear is when an asperite (I think of it is a stalagmite hitting a stalactite :) ) from one surface penetrate through the thin wedge of oil and collides with one from the another surface, they break, and that is wear. According to the tribology book, the perfect bearings is perfectly smooth surface so no part of one deviates enough from flat to extend through the oil layer and hit another.
 
Maybe because these machine builders tried to build reliable and good machines, in order to do so they did lots of testing to figure out whats gonna work best.

That might be true for some machines, but I don't think it's true in general. I think the OP is waxing nostalgic.

Machine builders were playing by different rules. They didn't have to worry about cheap containerized shipping from Asia. Japan and most of Europe were still rebuilding. Places like Taiwan, Korea, Vietnam, were no threat.

In a world largely before things like die casting of metals and plastics, machining of metal, especially iron, was the back bone of manufacturing. Before CNC, we needed precise machine tools to build tools and fixtures to allow less precise machines to do production machining. Those needs really no longer exist. I've been in a lot of machine shops. I can only think of a few places that have a jig bore or a jig grinder. Even machines like OD grinders and even surface grinders are being displaced by CBN tooling.

But all that said, I'm not sure those machines were all as great as we remember. I've worked on a lot of older American made machine tools. I've seen some really poor quality and poor designs that were never corrected. Some of the stuff that was built during the Vietnam war is really bad. The government contractors must have been buying anything they could get their hands on.

The other part of the equation is that the crappy machines from that era have long since hit the melting pot. How many thousands of engine lathes were built in the US for WWII and just after? How many are still around? Natural selection has weeded out the crappy and worn out machines.

It's just like when people come here and whine about how old tools were made with "better steel". They neglect the countless old tools that hit the scrap bin leaving only the outliers. We get a post like that at least once a month.
 
Survivor bias. The ones that weren't as derided as "pot metal toys" not worthy of discussion here, much less still taking up space in a working shop. Same reason old TV was better or foreign films are better. You never hear about the piles of dreck.
 
Another thing to remember- at the time, these machines were NOT cheap. They were very expensive, and held their value quite well. Before the mid 70s, when cheap imported machine tools began showing up, american made machine tools were quite pricey.

In the early 70s, a new Bridgeport, with no power feeds, just an ordinary manual mill, cost twice as much as a new Ford pickup. I had a friend in those days who bought a stripper Ford F150 for $2500. At that time a Bridgeport with a vise would run close to $6,000. Many of the bigger machines mentioned cost as much as an average house did, when they were new. In Seattle, near where I live, the AVERAGE price of a house today is $850,000. And I can get a cheapo, but usuable, taiwan bridgeport copy for six to eight grand.

Imagine if a current milling machine, like, say, a Lagun or a Wells Index, cost $90,000 today- that would be twice the average selling price of a new F150 in 2018. You would probably get hand scraped ways, for 90k.

I was just looking in a 1974 tool catalog- and a 10" Logan lathe was $4500, plus accessories- probably six grand, tooled and delivered. And that was when six grand was real money. I was making 3 bucks an hour then, and that was a decent, well above minimum, wage.
 
It seems to me that availability of quality machines is driven by market conditions:
- 60+ years ago, there were no CNC machines, and especially WW II and shortly after there was huge demand for industrial quality manual machines...so the very best and brightest were building these machines with a very robust industrial economy driving sales
- fast forward to now and the best and brightest and industrial demand is focused almost exclusively on CNC machines
- in the US, there is a glut of old manual machines that are being retired, and these are picked up by hobby users and small shops, but because there are so many high quality machines on the used market it totally suppresses any new machine market that might otherwise exist. There are a few holdouts (Monarch is still building new 10EE's in limited quantities).
- interestingly, in Europe (especially germany) there still exists manufacture of manual machines that are the equal of anything from the past, but even these manufacturers are relatively small, and I believe the market for these machines is driven by the very peculiar and unique social structure of industry in germany, switzerland, etc with many small family owned multi-generational businesses that still find use for these machines. I myself have recently purchased a Weiler manual toolroom lathe and an FPS 300 M (Deckel) manual mill from germany. They are indeed expensive, but if one looks at inflation adjusted prices, they are in line with the cost of similar tool room machines from 50 years ago.
- when one looks at productivity and accuracy, manual machines just cannot compete with CNC technology, and with the price of CNC machines dropping, they are a real bargain when compared to inflation adjusted prices of 50+ years ago, so it seems to me that technology has in fact dramatically improved the machines in mainstream use

Thus, my conclusion is that market conditions have driven the creation of quality manual machines...if the market conditions permitted it, we would still see same quality of manual machine being built, but those market conditions no longer exist and never will again....
 
I have been thinking about this thread for a while. I will ask a few questions to make you think about why? I walk thru shops and see a Sip or a Moore Jig bore or a grinder like the one Ballen had, a Studer that was still accurate after years of use. He was experiencing some stick slip but it was still accurate if your remember. Lets discuss why....why are those 1950 machines still accurate?

I do not know how long a 500K CNC will keep accuracy, as others pointed out, the machines you are thinking about would cost that much in today's money. 9" SB lathe would not keep accurate too long in daily use.

dee
;-D
 
Stuff was built differently when we could cast steel at such a low cost... and labor was cheap so everything was hand fitted. I personally find it more impressive at how good some of the modern machines are with less and less hand fitting. They nailed things down in the 20's-60's with one methodology. Then the world changed and the machines changed. An SIP jig borer or Monarch 10EE is something to be marveled... but if you look at that and scoff at a brand new Brother you have some real blinders on.

The truly impressive thing to me is how some of these modern machines can do millions of cycles and keep their accuracy...
 
Survivor bias. The ones that weren't as derided as "pot metal toys" not worthy of discussion here, much less still taking up space in a working shop. Same reason old TV was better or foreign films are better. You never hear about the piles of dreck.

I agree with all your points, however what physically in terms of science and engineering made one last and another.wear and lose accuracy. That's the Q, the people saying quality or they were better built doesn't reveal much. What exactly in engineering terms makes one keep its accuracy (imo that means not wearing) and another not
 
I love this discussion, just what I was after when I asked the question. Thanks for being so positive and offering your well founded opinions. I have some thoughts too, but will hold off for a bit longer. Thanks all !
 
They nailed things down in the 20's-60's with one methodology. Then the world changed and the machines changed.

It's not just the method of construction that has changed. In the 1950s, mechanical devices were cheaper than electrical devices. Today, in almost all cases, the opposite is true.

I think that helps to give the newer machines a reputation of being complicated and unreliable. Unlike mechanical devices, electronics don't gradually wear. They typically work fine until the day they completely die.

If a spur gear in a 70 year old machine wears out or breaks, we just measure it up and cut a new one, or find someone with an old drawing and cut a new one to spec. But, if you have a machine full vintage electronic gizmos, your options are limited. Often you are looking at some kind of complete system retrofit.

Some of the worst machines to keep running are those transitional era machines from the 1970s. For example, I worked on some American CNC lathes from that era with large spindle bores. These were built as CNC lathes, but they are really just converted engine lathes. They have something like 18 gear ranges in the spindle and no constant surface speed. Even worse, the servo motors had a gear reduction for the ball screws. So the servo goes through a pair of helical gears to a ball screw. The screw had a resolver on it for position feedback.

Anyway, they wanted to do a control retrofit, but it was going to be hugely expensive because the servo drive gears were worn and the backlash was going to play hell with the servo tuning. So the decision was to eliminate them which required fabing up complex adapters.

I've seen the same thing on Devliegs, especially the J model machines that were built as CNC machines. They were CNC machines, but they were really just old manual machines that they added CNC to. So they have all the complexities of the manual machines plus tons of unreliable vintage electronics and controls.
 
Another impact of machines having more electronics (as do cars, and just about anything else in our modern society) is that repairing such items is beyond anyone but the manufacturer, and even they might not be able to do the repair economicaly. That was not true of mechnical devices, a skilled machinist can repair/replace just about any mechanical part. And over the past 30 years, the electronics in most products are no longer "repaired", they are just swapped out, again because the complexity of the electronics is such that diagnosing and fixing is 1000x the cost of just swapping it out. The problem comes when the spare parts are no longer available, then you are toast. This is all driven by the exponential increase in the complexity of electronics....we all get the benefit of better and better machines that are cheaper and cheaper by virtue of more electronics, but lose the ability to fix these machines ourselves.

FYI, those of us who try to anticipate lack of spare parts and have a favorite machine will go onto ebay and build a spare parts inventory towards the end of life of a particular product, this can give one quite a bit of additional lifetime if you are a lite user of the machine. This is also what drives end of life decisions by manufacturers, when they run out of spare parts.
 
Hey Ya'll,
While I wax nostalgic about the 'good old days' and I do own and run old machines everyday.. I'm a job shop and not a production shop.. I root through the discarded/surplus old tools and machines and use what I can but there is only so much economy in dumpster diving..
Today's machines are accurate and FAST and are designed accordingly. Also there is a life cycle that is designed/planned into the tool. ( way too often designed to correlate with a rather abstract tax equipment deprecation schedule but once again I must digress lest I rant) CAD makes designing a tool with "acceptable minimums" much easier rather than the old way of designing a 'good', long lasting product. Life span is everything as is speed.. How many widgets can be made before the machine is depreciated and can be 'written off' ? That is the criteria of today rather than longevity.. Accuracy is there but longevity is not the issue it once was.
Another factor as I see it is a different mindset in the workforce ( just fyi it's limited to south central PA and central northern MD ).. While some care about their machines/work, most don't, and while not actually machine abuser's they tend to be very indifferent to care of the machines ( including their own vehicles !) that are in their charge. The old timers that I learned from would ALWAYS stop what they were doing before they knocked off for the day and clean their machines.. Regular oilings was done in the morning.. Things were wiped down and generally kept semi neat.. Today.. not so much.. neatness doesn't seem to count.. But then again maybe I'm entering into geezerhood..
Long and short of things is there was junk made back in the day and there is junk made today.. The good stuff tends to last and that's how the past is judged.. Today it's about speed of production as labor cost is through the roof so it only makes sense to have a machine that a monkey can run. Cost and speed and accuracy, it's what production has always been about..
Stay safe
Calvin B Haxton
 
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