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Re: Show us your lathe!

Posted: Wed May 08, 2019 5:20 pm
by spro
Very impressive and creative work, pat1027. We don't see that many South Bends of that age around. I believe these were the "N" series. I have a 1933 11" and has the same type QCGB and apron. The support of the co shaft and motor is really heavy biz. The reason is, course, these were designed for overhead line shafts. The line shaft cones presented "pulling up" of the spindle to balance the work load at the bearings. The way it was constructed with an individual motor , co shaft above, was the way to drive it. Mine has the "silent chain" drive and huge motor but only a project now.
Way Oil is your friend.

Re: Show us your lathe!

Posted: Thu May 09, 2019 12:17 am
by Jim Dobson
Here's a vid of some mods I've done to me Sieg C6 also sold as the Grizzly G0516, Hare & Forbes AL-60, Axminster Metal Lathe

Youtube -

https://youtu.be/5glxMpnOq_E

Re: Show us your lathe!

Posted: Fri May 10, 2019 7:08 am
by RSG
Nice Jim!

Re: Show us your lathe!

Posted: Sun Sep 13, 2020 4:46 pm
by LouStule
Here are some pictures of my Atlas-Craftsman Commercial 12x36 Lathe. I bought it about 10 years ago from a retired machinist friend and it's in really good shape. One of the things I really like about it is the fact that the motor sits below the lathe in that nice cabinet. This means that you can place it closer to the back wall in your shop. You may notice that I have it sitting atop some cinder blocks to bring it up a bit as I am 6'3". It came with a quick change gear box, the cabinet stand, a 3-jaw and a 4-jaw chuck and lots of tooling. I paid $1,000 for it. I built the sliding tool tray that sits on the ways behind the tail stock. I also added the light stand and the large tin oil pan behind the chuck ( the kind you put under leaky vehicles). That is handy for keeping oil and chips etc. off of the drywall. Also, I can use magnets to attach plans, diagrams and notes etc. to it. It's a great machine for my uses and I really like it. If you have any questions about this lathe please ask.

Re: Show us your lathe!

Posted: Tue Sep 15, 2020 11:17 pm
by spro
I had a Craftsman Atlas 12 x 36 lathe long ago. It had been crashed and I could see the repairs. The rear leadscrew mount was replaced by stronger support. The affected gears had been replaced to "working" . The QCGB had levers of iron and the idler gears appeared steel. I knew there was a heavier version of that lathe.

Re: Show us your lathe!

Posted: Wed Sep 16, 2020 12:16 am
by Steggy
JET 1236PS

JET 1236PS Engine Lathe
JET 1236PS Engine Lathe

JST 1236PS Headstock
JST 1236PS Headstock

Re: Show us your lathe!

Posted: Wed Sep 16, 2020 10:33 am
by NP317
Your lathe looks like a very functional machine for your shop.
Enjoy making things with it!
RussN

Re: Show us your lathe!

Posted: Thu Sep 17, 2020 4:11 am
by Steggy
NP317 wrote: Wed Sep 16, 2020 10:33 am Your lathe looks like a very functional machine for your shop.
Enjoy making things with it!
RussN
Thanks! It's undergoing an "engine swap" as we speak, so to speak. Out with the old single-phase boat-anchor motor and in with modern three-phase power. I actually was planning to do this some time in the future, but a good deal on the new motor came along and I decided to get 'er done now. A VFD will be next. I'll have some photos at some point.

Re: Show us your lathe!

Posted: Fri Sep 18, 2020 12:17 am
by neanderman
BigDumbDinosaur wrote: Thu Sep 17, 2020 4:11 am
NP317 wrote: Wed Sep 16, 2020 10:33 am Your lathe looks like a very functional machine for your shop.
Enjoy making things with it!
RussN
Thanks! It's undergoing an "engine swap" as we speak, so to speak. Out with the old single-phase boat-anchor motor and in with modern three-phase power. <snip> A VFD will be next. I'll have some photos at some point.
That should be a nice upgrade!

Re: Show us your lathe!

Posted: Fri Sep 18, 2020 3:34 am
by Steggy
neanderman wrote: Fri Sep 18, 2020 12:17 am
BigDumbDinosaur wrote: Thu Sep 17, 2020 4:11 am
NP317 wrote: Wed Sep 16, 2020 10:33 am Your lathe looks like a very functional machine for your shop.
Enjoy making things with it!
RussN
Thanks! It's undergoing an "engine swap" as we speak, so to speak. Out with the old single-phase boat-anchor motor and in with modern three-phase power. <snip> A VFD will be next. I'll have some photos at some point.
That should be a nice upgrade!
So I'm hoping. Also, powering a machine tool with a three-phase motor has a sneaky little bonus, aside from being able to easily vary speed with a VFD.

By way of explanation, in all motors instantaneous torque varies in a cyclic fashion depending on the line frequency and number of phases. A single-phase motor produces zero torque twice per AC cycle when the line voltage passes through zero at the end of each half cycle, the so-called crossover. The result is the motor slightly slows down at the crossover and regains RPM on the peak of the cycle. This phenomenon is referred to as angular velocity variation (AVV). It occurs at twice the line frequency in a single-phase motor.

When the motor is lightly-loaded, AVV has little effect on the machine due to rotating inertia. As the load increases to near the motor's maximum continuous output, AVV becomes more pronounced, since the smoothing effect of rotating inertia is a constant. If the motor is driving a machine tool, AVV can excite tool chatter or cause slightly jerky motion of the feeds. Precision can degrade if this happens.

In contrast, a three-phase motor exhibits much less AVV because instantaneous torque never drops to zero. This is because with three-phase power, at least two of the three phases have some voltage between them at any given instant. There is no "dead time" during crossover, since that happens at different times with each phase. The torque peaks and troughs occur at six times the line frequency instead of two times, but are much less severe than with a single-phase motor, producing much less AVV for the same loading. Hence the motor runs more smoothly under full load, which means the machine does as well.

Bottom line is converting a single-phase machine tool to three phase power can have a positive effect on precision and finish quality.

Re: Show us your lathe!

Posted: Fri Sep 18, 2020 4:28 am
by liveaboard
Single phase motors are an abhorrent historical anomaly caused by Edison's belief that domestic electricity connections were only for lights.
It's just incredible that a century later, this basic technical weakpoint still exists in most of the US.
Even central AC / heating would benefit from domestic 3-phase.
Anyway, the problem is now solved by the affordable electronic VFD.
Some new AC units come with integrated VFD for efficiency.
I have domestic 3-phase but changed my lathe to VFD power anyway.
It's wonderful; my basic old thing now has speed control, soft start, and braking.
Go VFD!

Re: Show us your lathe!

Posted: Fri Sep 18, 2020 3:58 pm
by Steggy
liveaboard wrote: Fri Sep 18, 2020 4:28 am Single phase motors are an abhorrent historical anomaly caused by Edison's belief that domestic electricity connections were only for lights.
It's just incredible that a century later, this basic technical weakpoint still exists in most of the US.
And to think that Edison wanted it to all be DC...

BTW, single-phase residential power is nearly universal in the Western Hemisphere—not just in the USA, and is also common in many parts of Asia. Much of the electrical infrastructure in Europe had to be rebuilt from scratch following World War II, so implementing three-phase residential power was a practical thing to do. Converting residential power in the USA to three-phase would be impossibly costly and impractical. This situation is analogous to the idea of electrifying all of our railways.