I've been going back and forth between building my own or just buying an affordable one but after seeing the one on the blog (somewhat) recently (http://hackaday.com/2016/01/05/diy-hakko-soldering-station/) I finally made the decision to go with the first option.
I'm not sure how much originality I can add to the topic but I figure a sort of literature review - if you will - might be worthwhile and helpful to others looking into building one.
Everything is quite rough at the moment but until I refine it a bit more check out the links themselves for more info.
If you have some more info on this topic that is not already covered, please let me know.
I made a quick measurement to see how linear the iron's temperature sensor is. Since I don't have a thermocouple I used a Pt1000 strapped to the heating element like this:
So I had one DMM measure the Pt1000's resistance and another one measure the resistance of the iron's sensor. Afterwards I calculated the temperature from the Pt1000's values and came up with this graph:
For now I just want to collect all the sources in one place. The list is somewhat sorted but hopefully I'll go over this list again and summarize all/most of them and maybe do some more sorting.
A quick heads up: There are a lot of duplicate links but I wanted to document for myself how/where I found the projects.
I already mentioned this one which was featured on the blog - I really like the option of driving two irons and the author makes a good point for the analog dial. He also proposes a mod for better heat conduction between the heating element and the tip.
#Soldering pen by @HP (@banjohat) - also based on the one by [Martin Kumm] linked above, very cool idea of integrating all the controls in the handle, made me think about applying this concept to the 907 iron/handle