06/16/2026
I've kinda been poking at models with sticks lately. Motivated to be at the bench but don't know what I want to work on. Hopefully I'll break through that block and start moving on a few projects. In the mean time Rod K***z donated an older Harder @ Harder & Steenbeck Airbrush Evolution to my growing collection. He's never been able to get it to work for him and I said I'd take a look.
So I got it a few weeks back after some coordination with Jake Ford to get it from him at RME. Disclaimer, I'm not an airbrush expert, but I'm pretty handy and enjoy repairing things. So what I got was the airbrush in it's original box, along with the larger and smaller cups for this brush, and a bag of miscellaneous seals. The brush was a bit dirty, like some one had gotten frustrated, did a quick flush and put it away, which tracks with what Rod had told me about the brush. I wanted to a quick test to see how it sprayed as it was so I loaded it up with some AK acrylic inks, set my pressure to around 20 psi and gave her a spray test. Something was definitely wrong, spray pattern was very course, had a distinct rectangular shape to it rather than the normal round shape and fine control was pretty much nonexistent. Also had bubble back into the cup. I also notice during my test that the top of the trigger wanted to rotate freely...that definitely should not be a thing on any airbrush. The trigger feel was also pretty stiff and draggy, which I chalked up mostly to being dirty.
Onto the figuring out what was going on. Started by flushing out the color I'd just sprayed through the brush, and noticed I got some small bits of stiff coming out with the cleaner, so I need to go beyond just a spray out cleaning. Out with the air cap, nozzle and needle and at this point I got the nozzle under my magnifiers and found the source of the weird shaped spray pattern and bubble back, the nozzle was split. That bit goes into the bin, the air cap follows and the needle goes into a tool drawer. Speaking of the needle there was a lot of drag pulling that out of the body, so I need investigate that a bit further, initial thought was that it was dirty and had some built up paint in it. I've already decided it's getting the whole new assembly from the 2024 Evo.
Next I tackle the body, I poke a small soft brush soaked with Tamiya airbrush cleaner through the front end and gently scrub. If you try this be very careful you don't run the metal shaft of the brush against the inside of the body, you could possibly scratch the finishes and create a spot where pigment will collect as the paint flows past. Scrubbed until clean, and then took a smaller diameter brush and got into the pack seal. That came out clean, so my thought that there was some built up paint in there falls short...now I'm taking apart the back half of the air brush, and either adjusting the pack seal or replacing it out right. Well I decided to replace it out right, simply because teflon seals do not spring back to their original shape and I fresh ones so what the heck, lets go. At this point the trigger also went into the bin, not sure what happened with the top of it, but it was loose and it was the older teeny tiny one, and they kinda suck. That was also replaced with an item from a 2024 Evo.
You all can guess the next step, everything goes back in the reverse order. The only thing that got extra attention was the pack seal with needs adjusted very slowly when you put it back in. My method involves turning the seal head in just until it stops, testing the friction of a lubricated needle as it passes through and making the tiniest adjustments possible until there is just a bit of friction. There you have adequate sealing and better trigger feel overall. Speaking of trigger feel, I like my triggers on the lighter side, and the Evo spring has a noticeable amount of preload and feels rather stiff. I could order a new spring for the 2024 Evo but I have a simpler solution, I trimmed out about a coil and a half of the existing spring. So I get a lighter spring feel without having to order a part. Everything else goes together like an airbrush should.
Final spray test was just what I would expect. Nice tight spray pattern, especially for an unadjusted medium, and the fine control was back. Sometime a little tlc goes a long way, and a little work can make something that's not working a real gem. Now my wife, who has decided that Maschinen Krieger is really cool, has an airbrush she can call her own and learn with. So big thanks to Rod for the brush! And stay tuned for Carries adventures at the bench!
Happy modeling!