Blitzkrieg - I googled it and it is a double action, actually they have the brushes and parts at www.obeeliks.com in Belgium. Its inner workings resemble an Iwata somewhat but I wasn’t able to get a clear enough pic of it to see if it was a clone. It looks like it would be comparable to the Iwata HP-CS with its’ 0.3mm Needle/nozzle… looks like a good brush! And the parts are at least semi accessible from obeeliks!
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I just noticed you ARE from Belgium so you essentially have locally available parts!
cool! let us know how it works out! It really does look good… for large coverage you might have to practice with that small needle/nozzle combo but it is possible! the good side of that is you are able to do camo without masking much!
Hansa belongs to Harder & Steenbek ( as Thayer & Chandler belongs to Badger ) so no worry about quality, but it seems to be an old model ( you can’t find it on the Hansa site : http://www.hansa-airbrush.de ); I suggest you call Mr Lermytte at Obeeliks as I know some major modifications were made on Grafos from H&S some years ago and they were not upgradable, so check you won’t fall short of spare parts.