build your own vap?

i was out walking today,i've been thinking about buying a vap lately and was thinking about the components involved-240v heating element(with a range of 100 to 300degrees controlled by a slide switch or user defined thermostat)a fan or pump,a case,a balloon with mouth piece(or some way to connect balloon/whip securely to the heater),a screen to hold herbs a set distance from element.
then it occures to me that the majority of components needed for the heating part are contained in a hair dryer(element,fan thermostat,on/off switch)if i was to put my herb in a sieve or screen and heated it with the hair dryer,and if it was the correct temp,and i could trap the vapors!,surely it would work like a normal vape?.could i just suck up all them tasty vapors?.i'm not gonna do this(only 1 hair dryer in my house and my wife would NOT be to keen on a crazy idea like this)but surely if the majority of components in a vap are the same as in a hairdryer,it can't be that hard to do a home made vap.if you bought the parts from maplin or sumthin would you be able to make your own and more importantly HAS ANYONE TRYED!!!!!!!