I have a water radiator on my top floor mounted in a small niche, so small that there is only about 1cm of space between the air-valve and the wall. The problem has been that I since I moved here 10 years ago have been looking for something that would fit so I could air out the radiator. But it seems like the closest I found was some image of one.
The last couple of weeks we have had quite cold weather and the need for getting the radiators up to max performance was needed more than ever. So after again spending a lot of time on google I just realized that I could make one my self. 3D print something out of PLA-CF.
The first version was basically a tiny socket with a hole though for some lever. In my case I chose a 2mm hex wrench. The design worked but it was quite fiddly to get in place and the wrench fell out at the worst possible time.
The second design added a “sprocket” since I realized that the socket didn’t need to be that deep. This improved the manoeuvrability heaps and the radiator is now free from air.
If you feel that you’d need your own you can download the files here: https://www.thingiverse.com/thing:6364238