[4]

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

[3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!

nashville_bill

Newbie
Registered
Joined
Feb 23, 2019
Messages
3
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
 

CluelessNewB

Active Resistor
H-M Supporter - Gold Member ($25)
Joined
Mar 3, 2013
Messages
1,182
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:
 
Last edited:

Ulma Doctor

Infinitely Curious
H-M Supporter - Gold Member ($25)
Joined
Feb 2, 2013
Messages
256
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 :)
 

nashville_bill

Newbie
Registered
Joined
Feb 23, 2019
Messages
3
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
 

CluelessNewB

Active Resistor
H-M Supporter - Gold Member ($25)
Joined
Mar 3, 2013
Messages
1,182
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.
 

markba633csi

Gold
Registered
Joined
Apr 30, 2015
Messages
3,354
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
 

GrayTech

Active Member
Registered
Joined
Jan 18, 2018
Messages
84
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.
 
[6]
[5] [7]
Top