The Word Clock - Arduino version

Step 2 The hardware - Make the controller board

Enough talk - lets start by making the controller board.

If you want to etch your own board, you can download the attached a PDF file and follow the steps I used.

TONER TRANSFER IS EASY

When I made the board, I photocopied the page onto Toner Transfer paper (Press-n-Peel Blue), then I used an old laminator to transfer the image onto a piece of very clean PCB stock.  I etched the board in a mixture of Hydrochloric Acid and Hydrogen Peroxide etchant.  There is a brilliant Instructable that describes the process at www.instructables.com/id/Stop-using-Ferric-Chloride-etchant!--A-better-etc/

BE SAFE

When you etch ANYTHING - make sure you are wearing safety goggles, and old clothing.

CLEAN UP

When the etch process is complete, everything was rinsed very well under running water to remove all traces of etchant.  Just before I rinsed everything, the etchant was collected for use with the next project.

DRILL HOLES

Once the board had been rinsed and dried, I used a Dremmel to drill the holes, and removed the Press-n-Peel film using some steel wool, detergent anf good old elbow grease.

This time, I took buckets of photos of the process - It is very pretty!

I personally really enjoy making printed circuit boards, and I am sure that you can make them yourself.  However, if you would like your own controller PCB, I am able to supply blank, or pre-assembled boards.  Have a look at the last step for further information.

Comments

[diy_bloke]

Great description of the process. As I would not know where to find the blue toner, I always use the very known method of printing on glossy paper with a laserjet and then use a hot flat-iron (yeah the one used for ironing clothes) and heat transfer the toner from the glossy paper to the copper.
But you are right, it needs to be spotlessly clean

[diy_bloke]

The hydrochloric acid/hydroxy peroxide combo is really great. Have been using that for some time now, no pore expensive ammonium persulfate, no more FerriChloride stains

[drj113]

Actually, the word clock has changed quite a bit since this article.

Have a look at http://www.dougswordclock.com to see how it has expanded.

I can provide you with a plan for the current PCB, or if you like, I am happy to send you a kit for either a full clock, or just a controller.

Doug

[thegnome54]

Hey Doug,

Thanks for the awesome instructables! Your clocks are beautiful and I'm hoping to make one for myself as a 'jump into the deep end' of working with electronics.

If you'll excuse my naivety, are there alternatives to etching my own board? Would it be a terrible idea to just use a big breadboard? I'm having a bit of trouble isolating which components of this project are actually essential to the function of the clock.

Thanks again!

-Guillaume

[drj113]

I forgot to mention...

Breadboards are ok for testing projects, but for something that you want to keep they end up being unreliable over time. The little springy contacts inside them go soft.

You really want soldered connections for long term.

Doug

[drj113]

Hi,

Thanks for the wonderful response. I have had many people be encouraged enough to make a clock that I decided to sell kits for them.

While the kits are expensive to ship around the planet (there is 1.7kg of acrylic) in them, I do also sell just the controller board or even just the bare circuit board itself. Jump onto www.dougswordclock.com to see whats available.

[ptorelli]

Is it really OK to dump this stuff down your drain during the rinse phase? You said it etches stainless, what will it do to pipes (or a septic system and leach field for that matter)!

[drj113]

Ahh - you make an important point.

If you have a septic system, do not dispose of this in the drain. Septic systems rely on a complex bacterial process that this will disrupt.

Here in Australia, we have plastic / clay pipes for the drainage, and by the time 250mL of used etchant has been diluted with 10L of rinsing water, there isn't a major hastle - especially as it gets further diluted by other waste streams as it traverses the sewerage network.

Remember that Hydrochloric Acit is used in swimming pools to alter the PH of the water, so once it is diluted it isn't a big problem.

The complexity hapens when you are dealiing with commercial quantities - most governments have rules about disposing of 50L of waste products like this.

[mattadamsnet]

I have always ordered boards and never made one and I would like to try. I don't have access to a laminator, are there any alternatives i could use? Would a clothes iron be too hot, is there anything else I could try?

[drj113]

I used to use a clothes Iron. I found that it was basically pretty good, but sometimes I screwed up the process, and wasted some press-n-peel. As long as your iron is on a cool heat - one of the synthetic settings, then it should be fine - just be patient. Send me an email ([e-mail]) - and I can sand you the Version 4 Atmega boards PCB layout PDF - the project has changed a lot since I published the instructable - the controller board is smaller, and it uses an RTC to keep accurate time.

[Fuggnuggins]

If I'm not mistaken your PDF is a metric sheet of paper. I'm having a hard time resizing it to fit properly. Don't suppose you could accommodate my backwards measurements?

[drj113]

I will try  Please give me a day or so - and I will re-print it to a diferent paper size.

[Fuggnuggins]

...And I had the wrong drivers loaded. I got it working fine. Thanks for the great instructable!

[drj113]

Whoot!

That is great - I would love some photos when you get your clock going

Doug

[kebabkiller]

 Is it just me being a bit dumb but are the jumpers just a piece of wire that connect two parts on the pcb

[drj113]

You are not dumb at all, that is a very reasonable question!

The jumpers are just wires to connect diferent parts of the PCB together.  I do not have the ability to make double sided PCBs, sowhen I need to link tracks where I can not do it on the copper side, I use a jumper.

I normally use a piece of resistor lead that I have cut off.

[jb77]

do you have an eagle file that you can email to me? [e-mail]

[drj113]

Eagle's free version can only be used for tiny boards.

These boards are 6 inches x 6 inches.  they have been laid out with easyPCB. 

[jb77]

 is it possible that you´d send the files to me ?

[shanemac]

 hey man - first off - this instructable is off the chart !!

but i cannot figure out why all the "blank" areas on the PCB are left with copper - is this intentional for reducing the amount of effort or is there another reason - sorry for the dumb question - i'm an electronics noob :)

[drj113]

I do this so that the amount of copper that I need to etch to make a board is reduced.  Saves time and makes the etchant last much longer.

[shanemac]

 Thanks Man ...thought it must be something simple like that :)