What is Levin "Hard" mean on a Levin lathe?

[LittleWatchShop]

What is distinguishing about "Hard" stamped on the headstock?

[nickelsilver]

Hard steel cone bearings in the head. They had a lower grade headstock for a while that used bronze bearings there. Honestly not a big difference, and many extremely good machines used bronze bearings. But the "Hard" was the cream of their crop (until they went with angular contact ball bearings).

[markr]

It's happy to see you.

[Neverenoughwatches]

7 hours ago, markr said:

It's happy to see you.

Haha there is few words in nickelsilver's explaination that i could JUMP on, but I'm just not going there. I'm  assuming the hardened steel bearings are less likely to GRIND to a halt if not regularly SERVICED. Just a thought as I'm not experienced enough to understand this TOOL and would hate to spark a BONE of contention on the subject so i will quietly EJECT myself away from the discussion in HAND. 

[LittleWatchShop]

OK, I won the bid and got the Levin lathe bed along with a "Levin Hard" headstock.  Lord, where is the brake pedal?  I think my lathe purchases are done...oh please!  I need to start getting rid of the ones I will no longer use.

Edited November 17, 2022 by LittleWatchShop

[nickelsilver]

I'll be curious if the head fits your other Levin bed, and if the tailstock lines up with both heads. In theory they should, but I have seen enough Levin stuff that wasn't interchangeable that it put me off them in spite of the high quality (except for their cross slides, being head and shoulders above all others I use Levin there).

 

Levin based their design on the WW or Webster Whitcomb 50mm center height lathe, made by the American Watch Tool Company (later Derbyshire). WW made all the heads and tails to a specific standard, to make sure they were all interchangeable. Other makers tried to do the same (I know Leinen succeeded). I have a hunch that certain eras of Levin lathe parts are interchangeable and then there might have been a shaky period and then who knows- though I would hope that the much later machines were better.

 

One of the most ball-breaking tasks I've done is hand scrape a set of Levin head/tail/bed that were all made at different times to match each other. It was a favor for a friend too, I think I got a bottle of something for it, haha.

[LittleWatchShop]

1 minute ago, nickelsilver said:

I'll be curious if the head fits your other Levin bed, and if the tailstock lines up with both heads.

This will certainly be enlightening. On my other lathes, the headstock and tailstock are serialized, so they were made together to match--even the bed is serialized.  As you noted, it appears that Levin does not do this...so...yeah, I am anxious.  I bought the ebay pair only because that was my only way to get the bed.  I plan to use the head/tail that I have on the newly acquired bed.

I have tested the head/tail on the bed that I have and they line up to the degree that I have been able to measure so far, so I am optimistic on the new bed.

Will probably put the HARD headstock back on ebay and just take what I can get.

7 minutes ago, nickelsilver said:

One of the most ball-breaking tasks I've done is hand scrape a set of Levin head/tail/bed that were all made at different times to match each other.

How did you do this?

[nickelsilver]

2 minutes ago, LittleWatchShop said:

How did you do this?

It's a basic process (hand scraping) that can generate very high precision; on its most basic level you can get a surface very, very flat, on average, and very well aligned, absolutely. It gets  really tricky when more than two surfaces need to make contact and be aligned at the same time, like a WW lathe bed, haha.

 

For this project one of the two (head/tail) was loose on the bed, the other tight. That's the angular sides' contact. I scraped the bed down to obtain good contact with the loose one (I don't remember which was which), then I scraped the tight one to have good contact with the bed. I made a reference flat that could contact the base of the head and tail (for blue spotting) and had another bed I modified so it could only contact one side of the angular ways to use as a tool as I was bringing the alignment in. It's hard to explain, but you can imagine that you get "one shot"- if you suddenly have full contact, but the (let's say tail here) is pointing away from the head, there's no easy way back.

 

 

[Klassiker]

Did some scraping at the start of my mech. eng. training over 30 years ago. Haven't felt the urge since.

[grsnovi]

We had a guy come in and scrape the ways on a horizontal boring mill. I forget how long he took but I was astounded.

[LittleWatchShop]

This Levin that I acquired a month ago came from a guy using it to turn shell casings.  He was not a watchmaker.  Likely that he bought the head/tailstock together. 

[dadistic]

On 11/17/2022 at 9:39 AM, nickelsilver said:

One of the most ball-breaking tasks I've done is hand scrape a set of Levin head/tail/bed that were all made at different times to match each other. It was a favor for a friend too, I think I got a bottle of something for it, haha.

Whoa! I didn't think *anyone* new how to do that anymore.  One of my early jobs was working for Sheldon Machine Corp, an old manufacturer of engine lathes. I worked close to a pair of old Polish guys, who hand scraped every lathe bed and croslide saddle that went through the factory.  They were amazing.

[LittleWatchShop]

1 hour ago, dadistic said:

Whoa! I didn't think *anyone* new how to do that anymore.  One of my early jobs was working for Sheldon Machine Corp, an old manufacturer of engine lathes. I worked close to a pair of old Polish guys, who hand scraped every lathe bed and croslide saddle that went through the factory.  They were amazing.

Maybe I should learn, but it looks both laborious and precise

[dadistic]

Time consuming.  Unless you are those guys I worked with, who had been doing it for years and years. 

The other thing I've thought about  trying is the three plate method to make a polishing plate. So far, I've resisted the urge

 

 

Edited November 19, 2022 by dadistic

[LittleWatchShop]

1 hour ago, dadistic said:

Time consuming.  Unless you are those guys I worked with, who had been doing it for years and years. 

The other thing I've thought about  trying is the three plate method to make a polishing plate. So far, I've resisted the urge

 

 

Well, I have stepped in it. Bought two lathe beds. Will pick the one I like and resell the other.

Edited November 19, 2022 by LittleWatchShop

[ifibrin]

On 11/18/2022 at 12:04 AM, nickelsilver said:

It's a basic process (hand scraping) that can generate very high precision; on its most basic level you can get a surface very, very flat, on average, and very well aligned, absolutely.

Can you do hand scraping on curved surfaces, such as a rod, while preserving a consistent diameter?

[Klassiker]

5 hours ago, ifibrin said:

Can you do hand scraping on curved surfaces, such as a rod, while preserving a consistent diameter?

I don't think so. How would you find the high spots?

[Neverenoughwatches]

9 hours ago, ifibrin said:

Can you do hand scraping on curved surfaces, such as a rod, while preserving a consistent diameter?

Accurately that sounds very difficult and time consuming by hand.

[nickelsilver]

On 11/20/2022 at 3:58 AM, ifibrin said:

Can you do hand scraping on curved surfaces, such as a rod, while preserving a consistent diameter?

Something like a lathe spindle would be precision ground (and probably lapped) between centers. Then, on machines with soft bearings, the spindle would be used as the marking master to blue the bearing, and it would indeed be hand scraped. Not in every case, but in many.