RCA 6146 Tube

EB5AGV's CDial project

Keep them glowing!

CDial (top part) CDial (top part)

What is a CDial?

A CDial is, as its name says a 'CD-dial' or, in other words, a dial engraved (and this is the difference with conventional approaches) on a CD-ROM. The CDial idea is twofolded: first, use those old CD-ROMs with outdated software or which produced an error while creating and second, give to your homebrew (HB) rig an special and unique look.

I have just made one CDial at the moment which is the one I have pictured in this page (by the way, it is very difficult to take pictures from a CD-ROM!).

The dial logging scale and markings are engraved in the 'data' side of the CD-ROM, so the label at the other side is of no importance.

Customizing your CDial

The CDial engraving can be customized to suit your needs in various ways.

The sample has a logging scale from 0 to 99, equally spaced in 360 degrees, but this can be changed to, let's say, 270 degrees and, of course, with other markings and orientation: the CDial sample I made was intended for FIXED dial and movable pointer, so the numbers would be always read fine (not upside down in any case). In case of a MOVABLE dial and fixed pointer all what is needed is to change the dial markings and put all of them facing to the center of the circle, as in a Collins S-line or KWM-2 dial, for example.

There is space also for the callsing ('EB5AGV' in my case, as you can see in the picture) or the builder's name or... what you want!

CDial (bottom part) CDial (bottom part)

In the bottom part you can put the name of your homebrewed rig ('HB-1 RX' in the sample).

The CD in the sample CDial is a writable CD-ROM and has a dark blue background. But I can use also standard (printed) silver CD-ROMs and also golden writtable CD-ROMs. So there are three possible background colors available: blue, silver and gold.

I use AutoCAD (by AutoDesk) to draw the CDial and can supply a 'template' which can be modified by the user and sent back to me with the customized CDial.

There is also the possibility to customize your CDial with a logotype. In order to do that, I would need an AutoCAD file (or DXF) with the logo to be added.

How is a CDial made?

I have received so far lots of kind comments about the CDial. Thanks a lot to all of you!. There is one thing some of you are wondering: how the engraving is made. Well, this is, of course, the hardest thing of all this project. I use a CNC machine (computer controlled mill in this case) along with a conical tool. It is a kind of plotter, but with a mill instead of a pen. It is connected to a PC which sends the data to the controller. Of course, that machine was not intended to engrave CDs ;-), so one of the toughest problem was how to fix the CD to be engraved without damaging it. It should be perfectly parallel to the milling machine plane, as the engraving is just 0.5 to 0.6 mm depth. Once this was solved there were other things which didn't work, as the CD plastic material melted instead of being cut... Some tweaking with the rotation and advance (XY) speed gave the final result, after some wasted CDs...

Ordering your custom CDial

I started this project as a personal way to enhance my homebrew gear and also to use those old CD-ROM instead of throwing them to the trash. But if anybody is interested in having a custom CDial made, I can offer them at a (I think) very reasonable price. As I have told before, a CDial can be customized with different dial divisions and markings to suit your needs.

I can offer them (including the support CD) for an introductory price of US $15 plus shipping for one unit and US $12 each plus shipping for two or more units. One good thing is that the CDial doesn't weight a lot and also it can be accomodated in an standard CD-ROM box for shipping so cost won't be high.

You can contact me by e-mail

CDial art ;-)

CDial - some light effects! CDial - some light effects!

CDial - more light effects! CDial - more light effects!

More ideas

I have been toying with the idea of doing some 'linear' (not round as a CDial) dial scales. I can use methacrylate, Lexan or other plastics as a support. Such an engraved dial, conveniently lighted (by the edges), could be very nice looking.

I can also engrave dual color plastic front panels, using a two layer plastic so, when you engrave the surface, you get the second color for the engraved parts. The milling machine controller front panel is done that way and it looks really nice.

Apart of the engraving, there is the possibility to cut the front panel or dial and make any needed holes.

Please, I would like to hear from you if you find anything of these interesting or you have any other idea or comment. This is my e-mail


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