Emerald Pendant

It was about time I made a piece of jewellery for my good friend Lou. She likes green, and I like precision handiwork, so I thought this pendant would make a nice birthday present. It features a 6x4mm oval emerald tension set in the central cutout, and two 1.5mm diamonds bead set at the top and bottom.

Graver Preparation

Attaching a handle to a new graver, grinding it to the right shape for use and forming a sharp, polished cutting face... [flickr-photo:id=1887220359,size=m]
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Z-Axis working

In the early hours of this morning the Z-axis was completed. A new, much higher torque NEMA-23 motor from Motion Control Products (part FL57STH76-2808B ) was added, along with a length of 10x3 trapezoidal leadscrew and nut from Marchant Dice . In addition an adjustable mounting was added to one end of one of the guide rails to allow them to be adjusted perfectly parallel. Here are the results of a pen pretending to isolation mill a circuit board layout. Video:

Submitted by jeff on Fri, 08/24/2007 - 11:41. categories [ ]

First output of the CNC table (videos!)

Over the last week or so, Rob and I have been working frantically on a CNC table for PCB drilling and general experimentation. I've been doing the mechanics, Rob's been doing the software and we've been working together on the electronics. See the flickr set for details of the build so far.

I'll be posting in detail about the construction later on. I've got stacks of blogging to do, but have absolutely no time at the moment!

Very early yesterday morning we got the first output.

Videos follow, in ascending order of awesome...

Submitted by jeff on Wed, 08/15/2007 - 11:49. categories [ ]

Hold the phones - inkjet

Thanks to Paul I just remembered another idea. Since the UV laser pulses are too slow for laser use (on further reading, 50% duty cycle is massively optimistic), use an inkjet printer. Have the output of the UV air laser connected to a fibre, and stick the other end of the fibre where the ink cartridge lives. Add some focusing optics on the end, and presto. 

Need to modulate the output of the laser according to the make-ink-go-now signal, and we're away.

So the next question is power density...

Submitted by jeff on Tue, 08/07/2007 - 17:26. categories [ ]

Direct PCB laser printing - a different approach

Recently I've rather gone off the whole direct toner to PCB approach. Just doesn't seem to be robust enough. Having recently fabricated some PCBs in the Chemistry department I've seen some of the insane artwork they use. The artwork is (or was, before it was outsourced) produced in the university printing studio. The artwork is staggeringly good - incredibly black. High resolution too.

The process is as follows: 

Submitted by jeff on Tue, 08/07/2007 - 14:05. categories [ ]

Agate Ring

I made this ring from sterling silver and a 10x5 marquise cut green agate stone. I like its bold, chunky, simple design. It is inspired by a piece by Carles Codina.

I started off by annealing a length of 3mm round sterling silver wire. I went for round rather than D-shaped as I thought it would look better with the chosen setting design. I heated it to cherry red and quenched in pickle.

DIY X-ray Machine

The other day I thought "wouldn't it be cool if I could make an X-ray machine for reverse engineering PCBs, etc". So I looked around and found an ancient Scientific American article. It seems that all one needs to produce X-rays is an HV supply and an evacuated tube containing a cold electron-emitting cathode and some kind of target anode.

Submitted by jeff on Mon, 04/16/2007 - 17:31. categories [ ]

PSP Wifi Reflow

I reattach the wifi module to a PCB from a Playstation Portable using my hot air reflow station.

Internal Bluetooth

I wanted to add internal bluetooth to my tablet PC, so I took a USB bluetooth dongle and shoehorned it into my tablet; adding a little control PCB to allow it to be turned on and off.