tur 2 engine

In our first post we present the motor that gave our site its name. The word "tur" in Polish means aurochs, the extinct variety of wild cattle, that is remembered through the "silny jak tur" idiom, corresponding to the English "strong as an ox". For many years domestic sewing machines produced in Poland were equipped either with a treadle built into a cabinet or table, or with an electrical motor tur 2. This motor was built from the mid-1960's by Fabryka Wodomierzy (water meter factory) in Wrocław, then from 1972-73 by the offspring company Przedsiębiorstwo Aparatury Spawalniczej ASPA (welding equipment company), and from 2007 to this day by another offspring company Zakład Silników Elektrycznych Asel (electric motor provider): http://www.aselzse.pl/eng/index.php?id=kn41. Some earlier machines could also feature one of the predecessors, tur or Fawod motors, we will write about them some day.

There were really many machine models with the tur 2 engine, some of them were sold worldwide under different vendor names, and sometimes the tur 2 logo is the only characteristic sign to the untrained eye. We would like to make model recognition easier. We will write about machine classes and names in future posts.

On the picure above you can see a metal pulley on the motor shaft covered by an isolation cap (more on pulleys below), two threaded inserts for attaching the motor to the holder, the socket for connecting the power and foot control cable, and the plastic screw immobilizing the lighting cable of the machine. The latter was pushed through a hole in the bottom, visible on the picture below, immobilized by the plastic screw, and the wires secured into contact by screws accessible at the inside of the socket.

The casing was fastened together with four screws accessible from the rear. The top left and bottom right screw in factory new motors used to be secured with a seal.

The back also shows a nameplate displaying the build year and motor variant, KN-4a with 90W power or KN-4b with 80W. Sometimes, as on the motor shown, there also was a serial number. The motor on the photo comes from year 1968, is of KN-4b variant, and its serial number is 86525:

Earlier we mentioned the pulley:

The metal pulley was secured with a metal screw to the insulating cap:

The insulating cap was snapped onto the shaft of the rotor in the long variant:

There was a variation of the motor with a short rotor shaft:

Such motors were equipped with a different pulley, all plastic with plastic fastening screw:

Later motors usually came with the metal pulley, but this rule was not strict. As the nameplate of the white motor shows, it was built in 1969, so after the black one on previous pictures:

Housings were either white or black or bicoloured:

Pictures below show the motor with the housing taken apart:

Inside can be seen the stator immobilized by two screwed down catches, the commutator and the fan of the rotor that is held by two bearings that are attached to the housing with two screws and a metal strip each, an electric lead that links the rotor to the core of the stator, the brushes and brush holders, the filtering capacitor and the electrical socket:

To finish, we would like to show a curiosity:

Yes, your eyes do not betray you, this is still the same motor, but branded tur 3. It seems that a batch of such motors was made for the German market, although this is still the same old KN-4a. This one came equipped with a plug, the same as in, say, modern radio receivers, to connect the machine's lighting:

We believe that no machine of Polish make was adapted to hold a corresponding socket, but we have seen photographs of East German machines Textima, Naumann and Veritas featuring it. If you, our dear Reader, have more information about tur 3, or about tur 2, than we do, please contact us.