Singer Heavy Duty Sewing Machine UI
Some of the symbols on the different pieces of the sewing machine interface are quite effective in terms of efficiency and memorability, while others are not.
Threading instructions might look like this:
This diagram makes threading a machine seem like a dauntingly complicated process. Designers are concerned about making it easy for the user to thread each individual point (labeled from 1 to 14 above) in the right way.
It’s much easier for humans to think of all these points as general movements.
Take this example of the first two points the user must interface with:
For step number one, the thread should pass through a flattened ring of metal. It is justifiable that the designer would add a thicker line interrupted by a simple square to give the impression that the thread should going underneath a ledge or loop. However, the straightness of the arrow conveys a sort of precision that isn’t required to do this process efficiently.
Simply looping the thread around point number two allows any user to thread both these points quickly and effectively. There are already pretty good affordances, which eventually make the user move in a single movement. For example, the user’s attention in this area is drawn to fat rounded top of the hook at point no.2, which is easy to hook a thread underneath.
Learnability should focus around this affordance:
Focusing on the movement the user should do to accomplish the task, and not what the task actually involves, can make an interface more learnable.
On other points of the threading interface, designers use this paradigm effectively because the thread passes by points that users cannot access. These interfaces have higher learnability:
For the step number four, notice the elevation of the plastic strip from the rest of the body, and the use of a slightly lighter colored plastic. These affordances suggest to the user that they might slip something underneath the end of this vertical strip, as emphasized by the hook-like arrow.
This interface has great affordances because the thread actually moves around these points in the same way that the user moves to thread the machine. By placing symbols in the right position to highlight these affordances, designers can thus guide the user through right movements on their first try.
The movement of the user should almost always relate to the movement of the object they control through the interface. This helps improve efficiency, learnability, and memorability.
I found the press-switch to make the machine go in reverse inefficient, because it was in a position that made it hard to press without removing my hands from guiding the stitch.
I looked into the position and shape of this interface to see how it was restricted by its mechanical function. In all machines, it must reverse the gearing of the foot at the bottom (circled in red below), and reverse the needle motion (circled in blue).
For the machine below, the switch is larger and wider, and can be activated with the right forearm. Unlike some of the protruding hooks for threading the machine — where affordances meant for ease of use and efficiency actually help with learnability — I only learned this trick when watching someone else use a machine with a similar switch.
Research showed me that many singer sewing machines have the same reverse switch placement as the heavy duty model that I found hard to use. In fact, this switch position is extremely common on a relatively large range of Singer models:
The Singer designers might keep placing the reverse button in this area to make functionality more obvious, especially since this is not a button that users use extremely often.
I think this is a case of trade-offs between efficiency and learnability. Trying to reconcile the two can lead to more confusion:
Removing the reverse symbol placed on top of the switch can at least add more learnability:
