Day 16 – Extension!

Yesterday, just when I thought I was half way done through this Circuit Breaker period, my Prime Minister announced that there is a need for an extension of an additional 4 weeks. Instead of ending on May 4th, this will continue until June 1st.

I try to take this sudden change as positive as possible; using this opportunity to build my engraving machine while familiarize myself with it if there is no need for trouble shooting.

Hand Piece

My GRS Quick Change holders from Taiwan arrived today. Yay!

Tried to fix it to my 3D printed hand piece but the hole I made was a bit too small. I require a hole which is according to my caliper, between 6 mm and 6.5 mm. Since I only have a 6 mm drill bit in my tool box, I quickly popped out to the hardware shop in the neighbourhood and got myself a 6.5 mm one.

While the 6 mm drill bit fits in my jeweller’s flex shaft, the 6.5 mm one does not. So I had to manually enlarge the hole. It felt and sounded a lot like sharpening a pencil.

With a 6.5 mm hole, I can now insert the holder, but it is a little loose. Does not matter, if  needed, I will glue the thing down at the front.

All that is left is fine tuning which can only be done when I have the whole machine up and running.

  1. With the holder sticking into the barrel, the room for the piston to move forward and backward has be reduced. I will try to balance it out, either reducing the length of the spring or the length of the piston (which means a lighter and less powerful piston).
  2. I am considering 3D printing a little cap where I can attached the graver holder onto to and then put it on the front of the barrel of my hand piece.
    This is a good way to make a bit more room for the piston and also, I feel it is better to fix the graver holder on something else instead of the barrel itself, so that I can easily make changes in the future.
  3. I find the length of my gravers to be too long for operation in this hand piece. Only way is to shorten them and I do not think I will enjoy cutting through steel.

Now that I have the actual graver holders in my hands, I cannot for the life of me, figure out how it  works. The holder itself looks like it is a single, solid piece. I always imagined that it would be like a two part thing with a front bit and a back bit, so the impact from the piston will be transferred from the back bit and into the graver held by the front bit.

That made me worried for a moment, thinking that I may have bought the wrong thing and there might be another version of the holders, one which is specially made for usage in pneumatic hand pieces. Immediately, I went through the online catalog of the graver holders and reassuringly, they all look more or less the same.

Hopefully, it works as expected when the time comes.

The Machine

It is 7:28 pm. Just came out of a quick shower to cleanse myself of the grim and sweat I worked up for the past 3 hours working on the homemade engraving machine as the speed control came in this afternoon.

According to Mr.Hughes’ YouTube video, I opened up the compressor and sealed up the piston of the macine. While the epoxy glue is drying away, I had to find a way to get the air flowing out from the machine. Unlike the compressor Mr.Hughes used in his video, the cover to the piston has nothing on the top, so he drilled a hole and put a tube through to his hand piece.

Of course, I was not that lucky. Right on top of the cap (the middle picture shown above) of my compressor, is this tube like form with led to the PSI meter and the original outlet. I got rid of both by sawing through the tube structure with my jeweler’s saw because it was the only saw I have. Amazing, I went through it without breaking my saw blade. It was hard work. What I have in the end, is a single outlet for the air. I will need to fix some kind of valve to connect one end of the silicone tube to my hand piece on the other end.

With that done, the last thing I need to do is the wiring. Mr.Hughes’ demonstration went pretty fast, and he did not touch on how to differentiate the positive wires from the negative ones. On the speed controller, it is indicated clearly on the four slots where the positive/ negative is supposed to go to and which pair belongs to the motor/ power source. In the video, Mr.Hughes’ compressor had two wires, red and white. He connected the red one to the negative slot of the controller and white wire to the other. My compressor’s wires are red and black, and since I did not want to think too much, I just take red as the negative wire like he did.

With compressor hooked onto the speed control, it was time to attach a power source. To be honest, I was quite worried that attaching the wires wrongly might result in a explosion or something. For the power source, both wires are black, so I just took a gamble. Then I plugged in the machine, put a bit of distance between myself and the machine and turned on the switch… It works!

Tested and working!

Now I just need to wait for my silicone tubes to arrive. Oh, I will find a suitable housing for to keep my machine.

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I design fine jewellery for a living.