New Lathe User - Just Bought An Atlas MK2 6x18

[Skowinski]

The Atlas Mk1 (which was never actually called that during its lifetime) consists of the Atlas 612 and 618, the Craftsman 101.07301, and the Craftsman 101.21400. The 618 and 101.21400 are exactly the same except for badges and nameplates, and both have 1"-10 spindle threads. The 101.07301 is almost the same as the 618 made in about 1938 to 1940 except has sleeve bearings and 1"-8 spindle threads.

The Mk2 replaced the Mk1 in about 1973. All have 1"-10 spindle threads and are 8-speed (no intermediate countershaft). The first two models were Atlas 3950 and Craftsman 101.21200. They have ball bearings on the spindle and a cast iron headstock. The first 800 to 1000 or so used the same compound and tailstock as the 618. As those were used up, they were replaced by what you have. The bed was originally the same as on the 618 except for the location of the tapped holes for the headstock and legs.

Sears discontinued the 101.21200 in 1976 or early 1977 and Atlas replaced the 3950 with the 10100 (which Sears never sold). Initially, the only difference was that the headstock (still cast iron) and spindle were modified to take Timken tapered roller bearings like the 618 had. In June 1979 at (supposedly) S/N 007328 the apron was modified to add backlash adjustment to the carriage traverse gears. At some point after S/N 008329, the traverse rack was changed from the 618 type (with 5 mounting screws and two locator pins) to only two larger screws. At some point no later than S/N 9901 and thought to probably be in early 1980, Atlas changed the headstock and legs to Zamak. This proved to be a disaster and although Atlas apparently made a retrofit kit with cast iron parts available (not clear if free or not), the 10100 went out of production probably late in 1980 or very early 1981.

Your machine has the late apron with backlash adjustment but I can't tell from the photo whether the legs and headstock are cast iron or Zamak. If you wouldn't mind, please complete the "Survey Questions For Atlas/craftsman 6" Mk2 Lathes" contained in the thread of that name up in the Sticky area at the top of this Forum.

Thanks for all the info!

The headstock and legs on this one appear to be Zamak - they are non-magnetic. Some of the documentation that came with it indicate it was bought from the factory in 1981. What's the issue with the Zamak parts, brittle, wear out easily?

Looking at the ways it's apparent this thing has little use. The tool/grinding marks are still visible front and back on both ways.

I'll do the survey for sure.

 

[Dhector]

The Atlas Mk1 (which was never actually called that during its lifetime) consists of the Atlas 612 and 618, the Craftsman 101.07301, and the Craftsman 101.21400. The 618 and 101.21400 are exactly the same except for badges and nameplates, and both have 1"-10 spindle threads. The 101.07301 is almost the same as the 618 made in about 1938 to 1940 except has sleeve bearings and 1"-8 spindle threads.

The Mk2 replaced the Mk1 in about 1973. All have 1"-10 spindle threads and are 8-speed (no intermediate countershaft). The first two models were Atlas 3950 and Craftsman 101.21200. They have ball bearings on the spindle and a cast iron headstock. The first 800 to 1000 or so used the same compound and tailstock as the 618. As those were used up, they were replaced by what you have. The bed was originally the same as on the 618 except for the location of the tapped holes for the headstock and legs.

Sears discontinued the 101.21200 in 1976 or early 1977 and Atlas replaced the 3950 with the 10100 (which Sears never sold). Initially, the only difference was that the headstock (still cast iron) and spindle were modified to take Timken tapered roller bearings like the 618 had. In June 1979 at (supposedly) S/N 007328 the apron was modified to add backlash adjustment to the carriage traverse gears. At some point after S/N 008329, the traverse rack was changed from the 618 type (with 5 mounting screws and two locator pins) to only two larger screws. At some point no later than S/N 9901 and thought to probably be in early 1980, Atlas changed the headstock and legs to Zamak. This proved to be a disaster and although Atlas apparently made a retrofit kit with cast iron parts available (not clear if free or not), the 10100 went out of production probably late in 1980 or very early 1981.

Your machine has the late apron with backlash adjustment but I can't tell from the photo whether the legs and headstock are cast iron or Zamak. If you wouldn't mind, please complete the "Survey Questions For Atlas/craftsman 6" Mk2 Lathes" contained in the thread of that name up in the Sticky area at the top of this Forum.

Told you. Isn't he something!!!!!!

 

[westsailpat]

Congrats on your score S , I for one would also like to know whats in the drawers . If this tooling is not in the drawer I highly recommend you get it . https://littlemachineshop.com/products/product_view.php?ProductID=4058&category=
Tool setting has to be correct and this will make it so much easier . Good luck with the new machine !

 

[Skowinski]

Thanks westsail, have a notice for the quick change tool post so I can get those when they are available. Here are some photos of the contents of the drawers. A bit of a mess right now, as I've just started arranging similar stuff. Like I said, not completely sure what all I have here yet.

 

[Skowinski]

Thanks everyone for the welcomes! I'm getting into this as I'm about a year away from retiring and want to learn machining and welding, as a support to my main addiction, motorcycles. I hope this doesn't become another addiction!

Hey, what happened to my swarf status? I kinda liked that.

 

[westsailpat]

Man you really did score . I see some tool holder blocks in there , those look good . Motorcycles ?

 

[Dhector]

There are a lot of very intelligent people on this forum and I don't consider me anywhere close to smart with machining at all but from my little knowledge on this stuff I must say you did good. Very good!!!!! The only thing I didnt get with my 3950 that you did, was some brushes. And about 95 percent of everything else!!!!! Awesome!!!!

 

[wa5cab]

Thanks for all the info!

The headstock and legs on this one appear to be Zamak - they are non-magnetic. Some of the documentation that came with it indicate it was bought from the factory in 1981. What's the issue with the Zamak parts, brittle, wear out easily?

Looking at the ways it's apparent this thing has little use. The tool/grinding marks are still visible front and back on both ways.

I'll do the survey for sure.

Noob,

Zamak V is a zinc alloy usually die cast that can suffer from something called Zinc Pest. It is caused by using zinc in the pouring process that is of insufficient purity, primarily lead. It may take years before it appears or it can happen fairly quickly. However for the most part anything Atlas that was going to fail from zinc pest has already done so. It is generally accepted that any Zamak V parts made after about 1960 aren't going to be troubled with Zinc Pest.

However, zinc pest had nothing to do with the problem with the Zamak Mk2 headstock and leg castings. To a first approximation, Zamak has physical properties that are of about the same close order of magnitude as the better cast iron grades. Had the headstock or legs been made of cast iron of the same wall thickness or cross section, the same thing would have happened. One could say that Atlas should have learned their lesson back in the early to mid 1930;s when they made some parts (like the compound slide) out of Zamak and they soon broke. But I am sure that no one was still around to remind the bean counters of what had happened the last time that inappropriate parts were made of Zamak. Probably you won't have any trouble with it. But if the headstock or legs do crack, just replace them with the cast iron versions which are fairly available on the used market.

But the gears and other Zamak parts on the lathe should be fine. The gears will not last forever. But neither would steel or cast iron ones and it's unlikely, considering that they are basically new, that you will live long enough to wear them out.

 

[wa5cab]

I forgot to comment on the haul that you made. You really lucked out out the accessories and tooling.

 

[Suzuki4evr]

First of all,welcome to HM.
Even in South-African money that is a great find asspecialy with ALLLLLLLL THAT tooling.I am kind of jealous,but congrats and enjoy making chips.You will learn alot here.