[Newbie] Motor and Pully needed for Craftsman 109-21270 Lathe

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nashville_bill

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I was just given a Craftsman lathe model 109-21270. It looks to be in pretty good shape, and has extra gears and an attachment for working on automotive starter commutators.

However, it didn't come with a motor, motor bracket or the pulley for the motor. Can anyone send information, or pictures, of the motor and pulley for this lathe?

Thanks,

Bill
 
I don't believe they ever came with a motor bracket. Most people just mounted them on a bench. The motor was sold separately and they recommended 1/4hp. I'm sure many ended up with up-cycled washing machine motors strapped down with all manner of jury rigged engineering. I believe they did come with a matching step pulley for the motor, When you look for a motor pulley try to find one with spacing between steps similar to those that are on the lathe itself. You will want a motor of about 1750 RPM, NOT a 3450 RPM motor.

This 1955 Sears Craftsman catalog shows the lathe on page 26:
http://www.vintagemachinery.org/pubs/222/2699.pdf

Google "109 lathe images" and you will find a few showing motors and pulleys.

Here is one image I found on the web showing a motor and pulley on some 109 lathe variation:
lathe48x6.jpg
 
Last edited:
a 1/4 hp motor would be sufficient to run the lathe

my suggestion (easy way, not much else is needed than belt and pulley)
56 frame
1/4hp
shaft diameter 5/8"(standard for 56 frame)
1140 RPM

that being said,
i have read that there was a small flaw in the design of the lathe.
the spindle runs too fast with OEM sized pulleys for most operators taste.

most folks run 1740 or 1725 rpm motors on machine tools.

a motor speed reduction to 1140 rpm would be a simple and effective means to achieve a slower spindle speed,
using the OEM sized step pulley.
(only if you were inclined or worried about higher spindle speed- a 17XX rpm motor would work too.)

if you have the desire and means, (cool way, but more intense set up and learning curve if not familiar with electrical installations)
why not make the power plant a 56 frame, 1/4 hp, 1740 rpm motor, 3 phase, and add an inexpensive VFD to control the speed ???? :grin:
inverter rated 1/4 hp motors are dang cheap these days, and the even the inexpensive VFD's are quite reliable.

there is also the option to run a DC motor(also cool way, less trouble to set up than 3phase/VFD, but more complex than simple single phase motor set up)
treadmill motors are quite inexpensive, and can be used
there are also commercially available 56 frame DC motors too in 1/4 hp that run on 90VDC.
MC40, MC60 , KBIC ,and other inexpensive PWM controllers are quite capable of being utilized as well.

if i can help out, send me a message :)
 
Thank you (CluelessNewB and Ulma Doctor) for all of this information. I'll search for parts and get back with more questions once I have a working lathe.

Bill
 
BTW I totally agree with Ulma Doctor on the slower motor, the only reason I didn't mention it is that they are a bit harder to find used and cheap.
 
Check out that chair in the background in post #2- wild
Nashville: lotsa folks salvage treadmill motors and controller boards for their lathes, that would give you variable speed, very useful
Mark
 
I have a 109, Dunlap. I suspect the slower motor would limit top speed too much. If it has the backgear assembly attached to the pulley in the headstock you should be fine with 1725 motor speed. A DC conversion with speed control could also be useful.
My 109 is mounted on 2 thick rails running the length for extra rigidity. It has a hinged motor bracket welded to the rear rail. I will try to get a pic later today. Motor pulley is approx 2" 3" and 4" diameter. Let me know if you want more accurate measurements.
 
Ulma Doctor said:
a 1/4 hp motor would be sufficient to run the lathe

my suggestion (easy way, not much else is needed than belt and pulley)
56 frame
1/4hp
shaft diameter 5/8"(standard for 56 frame)
1140 RPM

that being said,
i have read that there was a small flaw in the design of the lathe.
the spindle runs too fast with OEM sized pulleys for most operators taste.

most folks run 1740 or 1725 rpm motors on machine tools.

a motor speed reduction to 1140 rpm would be a simple and effective means to achieve a slower spindle speed,
using the OEM sized step pulley.
(only if you were inclined or worried about higher spindle speed- a 17XX rpm motor would work too.)

if you have the desire and means, (cool way, but more intense set up and learning curve if not familiar with electrical installations)
why not make the power plant a 56 frame, 1/4 hp, 1740 rpm motor, 3 phase, and add an inexpensive VFD to control the speed ???? :grin:
inverter rated 1/4 hp motors are dang cheap these days, and the even the inexpensive VFD's are quite reliable.

there is also the option to run a DC motor(also cool way, less trouble to set up than 3phase/VFD, but more complex than simple single phase motor set up)
treadmill motors are quite inexpensive, and can be used
there are also commercially available 56 frame DC motors too in 1/4 hp that run on 90VDC.
MC40, MC60 , KBIC ,and other inexpensive PWM controllers are quite capable of being utilized as well.

if i can help out, send me a message :)
Click to expand...
I just joined the Forum and have been looking for a post such as this one. Thirty years ago, I bought a Craftsman 109-21270 lathe from a newspaper ad. I have used it a few times, but only on crude projects as it does not cut smoothly. When I was teenager, my dad bought a Logan 9x48 and I made a number of parts on it. So, I know a little about running a lathe. Retired now, I am thinking about rebuilding the 109. Hopefully, I am not expecting too much from this lathe. Any comments about this would be appreciated. Tell me if I am wasting my time.

One thing I need for sure is a new motor, so this is just the post I have been looking to find. Thanks for the info.
 
MTucson said:
I just joined the Forum and have been looking for a post such as this one. Thirty years ago, I bought a Craftsman 109-21270 lathe from a newspaper ad. I have used it a few times, but only on crude projects as it does not cut smoothly. When I was teenager, my dad bought a Logan 9x48 and I made a number of parts on it. So, I know a little about running a lathe. Retired now, I am thinking about rebuilding the 109. Hopefully, I am not expecting too much from this lathe. Any comments about this would be appreciated. Tell me if I am wasting my time.

One thing I need for sure is a new motor, so this is just the post I have been looking to find. Thanks for the info.
Click to expand...
the 109's appear to be loved or hated, dependent on what the operator feels.
i would say that they are cool little machines for small turning operations
as i said in the previous post, the spindle runs fast with a 1740 RPM motor- an 1140 rpm motor would make a more useable powerplant
the spindles are small in diameter, a crash would not be a good thing
there are parts available
if the lil machine is not hurt too bad and you think it's worth the time to recondition, then do it!
you can only learn something from the process :eagerness:
 
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