The following is the beginning of a blog post I started in December, and was going to post on 1/1/2016. It’s almost August. I don’t think I’ll get back to it. Still, some interesting bits in there.
At the end of 2014, I was on the verge of having a 62MAS inspired dial made. Somewhere along the way, the LE Sumo was released, which kind of took the wind out of my sails. Of course the aftermarket version is readily available, but I was going to put a bit of my own spin on it.
I thought I had settled a few designs to start off with, but a few projects ended up challenging me to work out a way to make it happen in-house, or at least locally.
I started with trying to find indices or anything that could be used for indices, and perhaps figure out a template or some way to get the alignment correct. Despite how much I like my 6309 Lozenge (named for the tall white indices which look a bit like medicinal tablets), I didn’t want to go through the process of making them again; honestly, the alignment of the indices isn’t precise enough to send out to a paying client. My first thought was thick vinyl, cut by a plotter, but the results weren’t satisfactory, and though I could get the adhesive vinyl on cleanly enough, often there was warping and pulling so the dial was slightly askew. I next went to a local laser engraver hoping to have some plastic laser cut, but again, the results weren’t anything nearing production quality.
Along the way I had a couple projects commissioned that required metal framed indices. I was distracted from looking for solid white indices to some way to make index frames that could be adhered to the various surfaces I was working with. I ordered all manner of small metal tubes and cutters. Many attempts over the course of many weeks resulted in nothing usable.
Photo Chemical Machining was the next method I investigated. Another very time consuming process involving a high level of preparation, with some attempts resulting in decent definition, but others dissolving into disappointment and ferric chloride.
A basic PCM how-to (if you have ever screen printed, some of this will sound familiar – except you can use a screen over and over, and this is a one shot deal):
- Create artwork in Adobe Illustrator or other program
- Make the negative artwork (black will etch, white will resist)
- Print on transparency
- Prep & clean sheet metal with very fine grit sanding (3000) pads
- Turn out all UV light
- Peel front & apply resist film to metal
- Remove excess water, cover and let dry.
- Place transparency face down on the film, clamp in place
- Expose to high UV light – your time may vary, about 28 seconds ended up being my sweet spot
- REMOVE THE CLEAR BACKING FROM THE FILM!!!!! FOR THE LOVE OF ALL THAT IS GOOD DO NOT FORGET THIS STEP!!!!!
- Develop the film in caustic soda based solution for 1-2 min, flipping the piece every 30 seconds or so. Lightly brush the resist film, it will start to dissolve in the areas that were masked out by black.
- If you did not remove the clear backing, you know now… the masked areas are not dissolving. You can try removing it and developing it again, most likely you’ll have to go back to the “prep and clean” point in the list and start again- it’s only been about an hour and a half since you did it the first time.
- Rinse under water and let dry
- Affix to hanger, and submerge in ferric chloride tank with bubbling agitator, flipping and brushing every couple minutes.
- Every 5 min or so, rinse in water to check etching depth- but don’t worry, it hasn’t gotten deep enough yet. If you are working with stainless steel, you are going to be here for a long time, probably an hour.
- Dissolve the rest of the resist film in undiluted developer.
- Now you can cut out your dial on the lathe and figure out how you are going to paint it… which is not so simple as you might think.
I can’t tell you how disappointing it is to get to the end of that process and have nothing worth using, or see where the film was not well affixed to the sheet and your design has partially etched away. I spent a lot of time working this method over, and actually got it to a point that was halfway decent. I made my robins egg blue dial mini monster, and my sister’s creature dial with it. It is simply too time consuming and labor intensive. And your printer resolution will be surprisingly apparent in your etchings.
I had an order come through for a carbon fiber dial about midway through the year, and so I was also back on that track, looking for ways to make solid white indices. This resulted in spending some time working on mold making and casting.
Throughout all this, I was still trying to crank out the more simple projects as they came through, running my little watchmakers lathe to death working on cutting dials, chapter rings, perfecting my baby tuna bezel conversion, and of course, doing plenty of media blasting and Cerakote.
Maybe I’ll start the 2017 State of the Art now…
The quick finish version is that I hooked up with great laser engraver, got a new lathe (and mill, but that is 2016 material), and there is a lot of cool stuff right around the corner.