Radiator Bleed Key & Bottle

Prior to owning a printer I always used a filler funnel to bleed radiators.  The old funnel broke so I printed a new one in a bit of a hurry ( https://www.printables.com/model/1296317-radiator-bleed-funnel ) in order to get a job done.

Afterwards I thought I could do better - an integral bleed system to enable one-handed operation in difficult locations.

I was in the midst of Fusion modelling my “invention” when unfortunately, a quick Google revealed that it had been done before.  There are a couple of similar concepts available commercially! Nevertheless I think my design is better so I finished it off and printed.  So if you don't fancy buying one on Amazon…..

For my original version, I printed the key in PLA+ with 4-perimeters however if dealing with hot radiators the PLA suffers so print in PETG (I used PETG-CF) or PC.  The key needs no support.

The bottle is in PETG and will benefit from support in the spindle hole.

The key has a groove to take an 8mm x 2.0mm O-ring.  This keeps the assembly together and eliminates drips.  It would work without one if you don't have one handy.

p.s. If the bleed screw is tight, I use a steel key just to “crack it" and then use the bleed tool.  Nip it with the steel key afterward.