Oak & Acrylic Nixie Clock

I've always been fascinated by how things work, what makes them tick, and it turned into an expensive obsession of taking things apart. I was never very good at making things though, lacking the patience of process to get things just right, choosing to hack at things with little precision. Measure twice, cut once was the often ignored advice of my father.

In recent years though, I've started making clocks. First was an Arduino based binary clock which sat quite happily on my desk at work for a couple of years. It was a great talking point. I could read the time, but no-one else seemed to grasp the concept. The second was a Word Clock, again based around Arduino. The Third (which I still haven't finished) is a work commission for a Rasp Pi based 16x32 led panel. It will have 2 lines, for current time and meeting time elapsed. The only thing I need to do now is learn Python to get it coded!!

My Fourth clock project is the subject of this Instructable. It was searching the clock section of Instructables that I saw my first nixie clock and I knew I needed to make one.

Step one was to do some research and choose which tubes to use. I quickly settled on 6 IN-1s from an eBay seller in Ukraine. Before I knew it, I'd bought them and then scratched my head and started to wonder what to do with them.

Task one was to look up tube dimensions and I found out that the tubes had a diameter of 30mm viewable, with the main body diameter of 35mm. The tubes overall depth was 65mm. So these sizes would largely determine the size of my clock. So the paper and pencil came out. It needed to have space at the ends, gaps between the hours - Minutes - Secs, and it would be nice to have some neon colon indicators too. So a quick search and another eBay visit and 5 INS-1 indicators were ordered.

I think panic set in at the thought of drilling 6 perfect 30mm holes and 4 perfect 6mm holes in a chunk of wood. It this point, I was thinking of using a trinket box or similar and just cutting holes in it. I wasn't even sure how I would drive them (Arduino, Rasp Pi etc) or power them as they each require an unfamiliar 170volts!!

So next job was to decide what would make the clock tick.

The logical place to start was the 170V DC to power the nixie tubes. But seeing so many clocks around, it can't be so hard. can it? After much deliberation, I decided to go with PVElectronics brilliant 'Dink' remote tubes board which really did tick all of my boxes. In provided the power, the micro-controller to display the time, but in such an adaptable format. I just knew it was the foundation I was looking for.

Right, on with the design. So now I knew the size of the tubes, I also needed the case to 'hide' a smallish pcb and wiring.

Having decided on tubes, indicators and the 'brain' of the clock. All I needed was a pretty box. After 4 days on the iPad, searching for wooden boxes, I gave up and decided to make one. White and oak, the idea stuck after looking at my wardrobe, which happens to be, white with an oak top.

So with the design concept in my head, let's get down to business and sketch it out. Then decide on materials for the white part having already chosen a nice piece of oak for base and top.

It was a Youtube search for laser cutting that led me to RazorLab.co.uk who could laser cut me some MDF which I could paint white. Then I saw the white acrylic option and got really excited.

The tutorial to design the clock forced me to quickly learn Adobe Illustrator. So Youtube comes to the rescue again and before long, I was designing my clock front, socket holder, sides and back. All in bright white 3mm acrylic sheet. So while the learning curve shallows and the design takes shape, I'll turn my attention......

Sockets!!!!!!!!!! Oh no! I'd read that the sockets for IN-1s were like hen's teeth. So back to the drawing board (Google) to see how I can hold the tubes in place with resorting to hot glue and luck.

One of the best parts of any project has to be ordering the parts and waiting for the postman to call. The tubes were still on their way from Ukraine, the INS-1 indicators had arrived and I'd started to solder together the kit from PVElectronics.

It's worth mention that the kit from PV is superb, very easy to put together, with first class documentation. Highly recommended.

The sockets were still an issue, but one Saturday night, I'd found a reference to IN-1 tube sockets in a forum and the fantastic guy had linked a 3D model file a socket for my tubes. By 3:00pm the following day, i'd found a printer hub on 3D Hub, agreed a price and watched them being printed, live online. They were delivered on Wednesday of that week! I've included the main file to save you the search. I didn't have any issues with tolerances as the 08-50-0106 MOLEX crimps take up any slack between pins and sockets.

Kit built and tested, discharging capacitors read up on and crimp connectors ordered. On with the wires and a first plug in test..... held my breath and it worked! WOW...

Parts used so far:

• PVElectronics - Dink - kit for remote nixie tubes
• IN-1 Tubes x 6
• INS-1 indicators x 5 (needed 4)
• 3D printed sockets for IN-1 x 6 - from Wellmeadow's Hub on 3DHub
• 08-50-0106 MOLEX crimps x 100 from eBay - you need 66
• Red & Black insulated multi-strand wire 20g - Maplin
• 2.5mm heat shrink - Maplin

So that little lot got me my first nixie working...

I've probably gone overboard with the gauge of wire. I had become quite paranoid about the high voltages involved, so gone for heavier gauge wire that I really needed to.

Even so, there was the same number of wires to cut, strip, tin and connect together. One advantage of the circuit design is the fact that there are only 10 cathode wires, one for each digit 0 - 9 which daisy chain along from each tube to the next, and 6 anode wires, 1 going to each anode pin. So 16 wires connected to the board. But 66 wires all together, to be soldered together, plus the red anodes.

Molex crimps were connected to the wires, all spaced out differently to allow for gaps between tubes. A wooden board was used to hold the sockets while wires are inserted and tie-wrapped.

Each tube was then connected to a socket and the wiring connected to the circuit board. Trial and error was used to ensure the tubes all displayed the right digit at the right time. Fortunately made easier with PVElectronics startup sequence cycling through from 0 to 9.

Then came the task of making good the contacts between crimp and tube pin. Some were okay, others needed a very light drop of solder. Others felt like open heart surgery was required to start them.

The only new purchase for this stage :

• Roll of 6mm self adhesive cloth wiring loom tape (to tidy up the sockets)

So, with all tubes connected, soldered in as necessary, and all loom tidied with wiring loom tape. The clock had become, well, a clock. Just needs a house.

Using Adobe Illustrator, I put all of the built elements together and designed a pine frame to support the acrylic sheets. I managed to build the whole frame from different length sections of 30mm x 10mm planed pine.

A number of trips to different DIY stores made it clear that 30mm x 10mm was not an 'off the shelf' size. So I would need to have some cut to size. I found a timber merchant in Doncaster who claimed that no job was too small. After an email enquiry and a Saturday morning drive, this was proven true. My dimensions list was quickly converted into a bag of wood. This was then glued, clamped and sanded down to form the main frame, ready for the acrylic.

Parts used:

• Pine planed stripwood 30mm x 10mm
  
  • 302mm x 4
  • 282mm x 2
  • 90mm x 2
  • 34mm x 6
  • 26mm x 2
  • 20mm x 7
• Wood glue

I put all of my illustrator learning into practice and finished the design for front, back, sides and socket holders. It just doesn't make sense to cut holes (30mm, 35mm, 10mm, 6mm and 2mm) myself, when you can get the laser to do it.

I'd also put some engraving detail into the design, for the logos and 12V socket label.

My completed design was sent off to RazorLabs and verified. It went backwards and forwards twice as I'd missed a couple of lines and deleted their template outline, so the design was actually bigger than my first material choice size. Dropping the design into their larger material template did the trick and the design re-verified.

I must admit to feeling very proud when it was delivered. Carefully opening up the package and inspecting my design, in the flesh, so to speak.

The tubes were then attached to the acrylic socket holder with 10mm M2 nuts and bolts. Then the whole panel, now complete with tubes, was glued to the pine frame using epoxy glue.

Parts used:

• Laser cut 3mm white acrylic sheeting
• 10mm M2 nuts and bolts
• Epoxy glue

While searching for oak for my clock, I was strangely drawn to a seller in Pickering, North Yorkshire, UK, who was offering off-cuts of oak left over from larger projects. Several of which were the right size for me. It was the fact that he oak was locally sourced that appealed. In a project which has so far used nixie tubes from Ukraine, 3D printed sockets from Shrewsbury UK, acrylic from London, nuts & bolts from China and wiring loom tape from Germany, it seemed right to use the stand-out material of the project from a local source (40 miles away).

So I ordered a small piece and it was delivered 2 weeks later. This was cut to size and sanded. Then the pcb was mounted using 30mm M3 countersunk bolts into brass hex M3 stand-offs, then the pcb was secured using nylon M3 washers and bolts.

The INS-1 indicators were pushed through the 6mm holes in the front acrylic and wires put through the 10mm holes in the socket acrylic before the front was glued. Next, the whole front assembly with the tubes was glued and clamped to the oak base.

Parts used:

• Kiln dried oak - 320mm x 250mm x 24mm
• 30mm countersunk M3 bolts x 4
• 15mm brass hex M3 stand-offs x 4
• M3 nylon washers and bolts
• Wood glue

We'll come back to the oak soon.

The pcb has 3 small push button switches to alter time, alarm, settings etc. This will be hidden inside the clock. So the next stage is to add some nice remote switches.

I'd found the switches in Maplin, but refused to pay the £7 each they were looking for. So I found some on eBay for £1 each from China with an orange 12V led angel eye.

From the spec sheet, I needed to cut 16mm and 18mm holes in front, and 20 or 25mm holes in the back, to secure the nuts. So a pack of flat drills was ordered and quickly delivered. It was with heavy heart that I drilled into the lovely piece of oak, but it was worth it.

One of the design bonuses on the Dink circuit board is a facility for 'show' leds. So a builder can install a row of leds to light up the tubes. It happens to be a 12V supply and, better still, you can programme the leds to switch off at night.

So more wire, solder and heat shrink. 4 cables were soldered to the main board, just before it was secured onto the oak base. These were then connected to the new switches.

Parts used:

• 12Volt stainless steel orange angel eye switches x 3
• Red & Black 20g multi-core wire
• 2mm heat shrink

Next was the back. The rear acrylic was glued in place on the rear pine frame. The 12V power supply socket was installed and the rear frame assembly glued to the oak base.

The acrylic sides were then cut to size and glued in place, hiding the rest of the pine frame.

To finish off all 4 corners, I bought some 4mm oak strip wood from the Cornwall Model Boat Centre. These were cut to length, sanded and glued in place. I think they finish the corners off lovely.

Once the sides and corners were done. It was time to literally put the lid on the project. So a generous amount of wood glue was applied and the whole thing clamped up.

Parts used:

• 90mm x 4mm Oak strip wood - x 4
• Wood glue

Once glued up, the only thing left to do was protection.

Self adhesive felt was applied to the oak base to help protect furniture. Next the oak base, top and strip wood was treated with 3 coats of Danish Oil to give a beautiful satin finish. It now has pride of place in our office / spare room.

I do hope you've enjoyed my journey and if you have stayed with it, thank you.