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Making a gilt dial (not decal)
- Thread starter chrome72
- Start date
yes I’m still in the learning zone. Many methods to do a mask and each one has its learning curve. I’m willing to bet you’d get a prefect transfer with your experience. I don’t plan on using black oxide on the final product. I’d be aiming for black nickel. It’s more to to show contrast and how well the mask held. I know I have some learning still. Seeing your results over time I’d consider using the film free method also.
That´ s photo printing. As mentioned a few posts earlier, the process that is used for decades to make printed circuit boards.
What you see in the photo is "smoky nickel" plating on copper. Was a bit surprised it worked quite ok, there was a "best before 08/2009" sticker on the photo coated PCB material. The mask that I have used is a professional resolution test sheet on film, not laser or ink printed at home. With fresh photoresist, mask on film, correct exposure time, correct concentration of the developer (and not touching anything with bare hands
) it should be possible to get the resolution down to a dot size of 20...30 micron. This was literally a quick and dirty experiment, that took me 20 minutes.
What you see in the photo is "smoky nickel" plating on copper. Was a bit surprised it worked quite ok, there was a "best before 08/2009" sticker on the photo coated PCB material. The mask that I have used is a professional resolution test sheet on film, not laser or ink printed at home. With fresh photoresist, mask on film, correct exposure time, correct concentration of the developer (and not touching anything with bare hands
) it should be possible to get the resolution down to a dot size of 20...30 micron. This was literally a quick and dirty experiment, that took me 20 minutes.Sometimes I feel like I am missing the boat here. I am guessing you are suggesting to actually etch the minute tracker, font etc to provide the negative relief? Then plate, then remove the mask?
I have seen others using transparent film to etch and not have to rely on transferring toner to the board. This would give you a lot better results, because you could control the placement of the image and not have to worry about messing up toner. Got any more info on your process?
I am pretty confident that the masking part is the uphill battle, plating should be pretty straightforward.
I have seen others using transparent film to etch and not have to rely on transferring toner to the board. This would give you a lot better results, because you could control the placement of the image and not have to worry about messing up toner. Got any more info on your process?
I am pretty confident that the masking part is the uphill battle, plating should be pretty straightforward.
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You can apply a negative or positive mask. That means leave the text exposed or leave everything but the text exposed.
1. The masking is applied to the polished dial, the text is masked, everything around will be plated black. The mask acts as an electrical insulator in this case.
2. Plate the whole, blank dial black, apply a negative mask, leaving the text exposed and etch the unmasked, black plating away.
Will try option 1 next, black nickel on gold plated brass, as soon as I get a fresh photoresist. I understand this was the original rlx process.
I could find Bart Cordell´s dial templates as jpg, are they available in an uncompressed or vector format?
1. The masking is applied to the polished dial, the text is masked, everything around will be plated black. The mask acts as an electrical insulator in this case.
2. Plate the whole, blank dial black, apply a negative mask, leaving the text exposed and etch the unmasked, black plating away.
Will try option 1 next, black nickel on gold plated brass, as soon as I get a fresh photoresist. I understand this was the original rlx process.
I could find Bart Cordell´s dial templates as jpg, are they available in an uncompressed or vector format?
In the print industry, a photographic film is used as a master, exposed using an imagesetter -> http://printwiki.org/Imagesetter. Very high res, sharp and opaque. Online service or printing shop, 10eur for a letter/A4 page.
So basically you create the master image on essentially transparency film, apply photosensitive film over metal, apply master image and develop in light?
it´s just one more step. The photoresist reacts with UV light and needs to be developed after exposure. The developing solution, in this example a 1,5% sodium hydroxide in water, washes off the exposed areas. A negative photoresist works the other way around, the exposed areas will remain.
This is more details on how omega speedmaster dials were plated and thus turned tropical. It pretty much says the same thing I am saying. Black nickel + Nitro cellulose lacquer. It’s the breakdown of the lacquer that allowed the tropicalization to happen.
https://www.watchbooksonly.com/articles/watch-reviews/speedmaster-chocolate-dials/
I want to make a Mitsukoshi panda dial for the speedmaster with galvanic white and black, and borrowing water slide decal tech for minute markers. Another day. I just need one of those st19 speedmasters now.
https://www.watchbooksonly.com/articles/watch-reviews/speedmaster-chocolate-dials/
I want to make a Mitsukoshi panda dial for the speedmaster with galvanic white and black, and borrowing water slide decal tech for minute markers. Another day. I just need one of those st19 speedmasters now.
When I get up and perfect this method I will be sacrificing a dial to the weather gods. I live in Houston, TX and 1,0000% humidity, 100 F degrees temps and intense sun are right around the corner. I just got a non-synthetic nitro cellulose lacquer so we will see what happens.
Though I like the results I get using film-free decal method, today I tried to make a 6538 using black chemical coating ...
Not bad for a first attempt ... and maybe I should spend more time on this ...
Well your first attempt blew my best attempt out of the water! What are you using for your black coating? Did you do double layers of film free?
- 13/10/16
- 3,917
- 2,391
- 113
I used hematite for cold coating ... hematitte is a mix of selenium dioxyde, phosphoric acid and copper sulfate ... please don't ask me about the % cause I have no idea ...
I used just 1 layer of film-free decal ... next trial I'll use 2 coats ...
And I'll spend much more time degreasing the dial plate before chemical coating, I'll probably let it soak for some hours in hot water with dish soap ...
Another quick test with the photo-coated PCB material and an ink-printed master. I didn´t expect a good result, the print is not 100% opaque and quite grainy.
The blue light in the background is the UV exposure unit.
PCB material with the protective foil partially removed, just before placing it in the UV exposure unit.
and after 3 minutes sunbathing ... into the developer solution.
20 sec...
30 sec...
40 sec...
fully developed and rinsed. As expected, bad ink-printed master, not good.. shit in - shit out.
The blue light in the background is the UV exposure unit.
PCB material with the protective foil partially removed, just before placing it in the UV exposure unit.
and after 3 minutes sunbathing ... into the developer solution.
20 sec...
30 sec...
40 sec...
fully developed and rinsed. As expected, bad ink-printed master, not good.. shit in - shit out.
As expected, bad ink-printed master, not good.. shit in - shit out.
however advice for where not to go and 1 inch (for the friends across the pond thats 25.4mm) closer to a quality process.
I ordered my plating kit, photosensitive film, and found a place near by that will create the high res transparency if i go that route, otherwise my local Staples will print a transparency on the cheap.
fully developed and rinsed. As expected, bad ink-printed master, not good.. shit in - shit out.
The black portion is the mask correct?