Day 18 – Over Engineering

02:15 AM

The silicone tube was delivered last evening, which means I have everything on the list. I hooked everything up for a test run and was quite disappointed by the result. Granted the valve on the compressor came a bit loose halfway during the test because I didn’t give it enough time for the epoxy to cure properly.

The piston just wasn’t generating enough impact to make the graver cut anything. My first suspicion is that the valves which I have placed on both the compressor and hand piece greatly reduced the force of the air from the compressor. I may have over-engineered things by designing the valves.

I have also listed down a few other solutions that will allow me to increase the power. When I wake up later today, I will work through my list one by one.

04:58 PM


Spent the whole afternoon trying to maximise the force from my compressor. I noticed that while the force right at the start of my compressor felt strong enough, as soon as I insert the tube in though, the force weakens significantly at the end. I doubt it is enough to move my pistol around hard enough to create any meaningful impact.

The tube structure on the top of the cap could be a problem. Like I have mentioned, because the cap of his compressor is simply flat, Mr.Hughes drilled a hole right on it and inserted the tube.


  1. I have ordered another compressor online. That is another $35. However, this compressor looks exactly like the one he is using. Also, the air flow is 35 L/Min while my current one only hits 27 L/Min. The most important thing is, hopefully, this has a flat cap for me to insert a tube directly.
  2. While waiting for that to arrive, I will continue to tinkle with the current one.


The 3D printed resin caps are starting to crack.  And maybe they are a little too loose inside the barrel. Also, perhaps the inner wall of my barrel can be a bit smoother.


  1. Need to find another piston. Ball Bearings again? Ugh. I have placed an order for 10 mm ball bearings.
  2. I am considering sticking a PVC pipe or copper tube into the barrel so that the inner walls are more consistent.

Hand Piece

The air input hole is too small.


I have reprinted another one! Behold! Hand Piece Handle V2!

That is that.

07:39 PM

Watched the video again. Caught a vital piece of information which I have missed. The spring to put inside the barrel with the pistol is damn important, apparently. What I want is the softest spring I can find. Hmmm…

All is not lost. Let’s look for the softest spring ever!

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I design fine jewellery for a living.