anyone knows who made the craftsman block grinders with the 115. prefix? i have 1/4 horsepower one i picked up for $5 at a relatives friend yard sale. Actually i had about 4 other items included for that $5 bucks as well.
Packard Electric (Division of General Motors) Purchased by Delco in 1932
What Outlaw said. ^^
Note: That style/model has an internal switch in the RH housing. Care is needed when disassembling. The centrifugal sw will be damaged if the bearing stays on the arbor/shaft when separating the housing. There are detailed restoration threads that can guide a disassembly, let us know if you'd like the links.
Also, from the thread: "Craftsman Block motor Bench Grinders - What's the Fuss (with resource information)", see link in my signature line for more information.
CM Block motor style grinder
Re: Vintage Craftsman "Block Motor" bench grinder info -
« Reply #11 on: February 05, 2012, 07:50:25 AM » goodfellow
A point of clarification. Sears sold many "block motor" designed grinders from several manufacturers, but the block design must be considered secondary. Of primary concern is the manufacturer.
The best engineered, most durable, and desirable "Block Motor" grinders were made by Paramount/Allegretti & Co.
These grinders have the 397 or 257 serial number prefixes.
Overall, the "Block Motor" designs were also made by Rixon, Royal, and B&D -- just to name a few.
These grinders do not have the higher quality field windings and castings that the Paramount/Allegretti units had.
Re: Vintage Craftsman "Block Motor" bench grinder info -
« Reply #38 on: August 14, 2012, 10:15:50 AM » toolguybak
Source code 115 is Packard Electric (Division of General Motors), which included Sunlight Electric Motors (and grinders) back in the 1930s.
Source code 257 covers Allegretti & Co and Paramount, who continued the Delco models for Sears.
Source code 397 is Delco (Division of General Motors).
Re: Vintage Craftsman "Block Motor" bench grinder info -
« Reply #40 on: August 15, 2012, 02:14:56 PM » toolguybak
The Packard Electric grinders (115) have the centrifugal starting switch on the rotor, like their regular motors.
The centrifugal switch is a pair of weights connected by springs, that slide an actuating sleeve.
The actuating sleeve engages or disengages a contact ring mounted on the end bell for the start windings, based on rpm.
The Delco grinders (397) and subsequent 257s have a starting relay instead.
I believe all of the 6" grinders were split-phase.
Some of the 7"x¾" grinders were split-phase.
Almost everything else was capacitor start.
General speaking, the commercial grinders are rated for industrial use and dual voltage.
The non-commercial grinders are usually single voltage 6" and some 7" for homeowner use.
