The phrase "as a contraption" is correct and usable in written English.
It can be used to describe something that functions as a mechanical device or gadget, often with a connotation of being complex or unusual.
Example: "The inventor showcased his latest creation, which he proudly referred to as a contraption designed to simplify household chores."
Alternatives: "as a device" or "as a gadget".
Sink thought the travois was not as good a contraption as Indians claimed.
So huge a presence is he that it is almost startling to find him arriving for a rehearsal of Wagner's Der Fliegende Holländer (The Flying Dutchman) at the Royal Opera House on as modest a contraption as a bicycle.
It is nighttime, and as he puts a contraption on his head, his wife, also in pajamas, enters the kitchen and asks what he is doing.
Takoyaki ($4.75 for six) is the faster of the two dishes, and it's fascinating to watch the chef as he uses a contraption resembling an electric sifter to pour batter onto a griddle that looks like a metallic egg carton.
(9) Dog-walking machines, 1937 "Very often it's the owner what leads a dog's life," says the voiceover, as he introduces a contraption to make the dogs think they are really running, "so the inventor of this little gadget deserves to be the benefactor of the human race".
The rock audience had never seen her like: a beautiful young woman, perched on a chair at the lip of a nightclub stage, plinking the 47 strings of a contraption 10 times as large as a Gibson Les Paul.
Both kids are fascinated by the piano as a noisemaking contraption.
The skateboard started off early in the 20th century as a scooterlike contraption made from two roller skates attached by a two-by-four plank.
He tried to capture its character – which he described as a "diabolical contraption, a dusty hunk of electric and mechanical hardware that reminded me of the disturbing 1950's Quatermass science fiction television series" – in a near-lifesize two metre by three metre Portrait of a Dead Witch, which he also intended as a joke about the contemporary craze for computer-generated art.
