Boardburner2:
My feeling was to go with standard etch resist then print with UV opaque ink , not done the experiments yet though as i did not want to feed unknown ink though a fairly exspensive printer.
Am I correct to think that you mean the you would coat the board with UV sensitive etch-resist and then print on top of that with UV opaque ink which would protect the etch resist when the board was exposed to UV light?
Your link reminds me of the main reason I got rid of the Epson R1800 - it would not work unless there was ink in all the cartridges. I think if I was to go down the route of adapting a printer I would also want to figure out how to make it work with just one cartridge.
And another thought ... I think I have seen web pages where people printed onto boards with laser printers. The plastic stuff that laser printers use for ink is etch resistant.
It is also supposed to be possible to laser print onto a transparency or the smooth support-sheet that sticky labels come on (after the labels are removed) and then using a domestic iron or a laminating machine to transfer the image onto the part to be etched. I got a sheet of transparency printed and I tried once to iron the images onto brass but it did not work well and I got sidetracked on other things (which is very common with me). If that process could be made to work reliably I think I would buy a cheap laser printer.
At the moment I have been cutting etch masks from self-adhesive vinyl using my Silhouette Portrait cutter. That works well but does not allow for very fine detail.
I have been electro-etching my brass using salt water as the electrolyte so no dangerous chemicals to be managed. I didn't consider etching at all before I recently discovered electro-etching thanks to Duck Duck Go
Boardburner2:
Oddly enough it was the silouette cameo i was going to mount by print head on as it canaccomodate 2mm thickness.
That seems to be a new feature. AFAIK it used to be 0.8mm
I wonder if the Curio would be a better starting point for PCB printing because it has a tray to hold the material.
However, first it is necessary to figure out the print head
A few hours with Google (actually Duck Duck Go) suggests that one can buy other brands of pigment ink that can be used with an Epson printer and which can be "fixed" with heat to make them resist the etching process. And from what I can see the Epson Durabrite ink is waterproof and that may be all that is needed for my electro-etching.
There are aftermarket uv cure inks for epson but they are the devil to remove afterwards also have to flush the head after a print run.
Bubblejet printers which depend on water based inks for operation do not seem to feature.
Although the epson inks are mostly water based i think they may be too viscous for bubblejet.
Robin2:
However, first it is necessary to figure out the print head
Yes.
It will almost certainly require a DSO or data analyser neither of which i have.
For bubblejet heads there are many connections and their spacing does not lens thamselves pogo pins.
Either way it is a challenge.
I've been doing some browsing and this looks like a really cool idea - paint all over the surface with a permanent marker and then scrape away the ink from the areas that you want etched. Some sort of scraper in a Silhouette pen-holder should work. or maybe even a regular blade that is past its best-before date.
The brass that I want to etch is probably thin enough to go into my Portrait cutter - 10 thou is just 0.254mm.
GoForSmoke:
If you have your board with photoresist and lay the printed transparency over it, will the image block the UV well enough?
As far as I know it does and with either an ink-jet or laser printer. But I am hoping to avoid photo-resist as it adds another stage to the process (and chemicals).
At the moment the only "chemical" I need is salt water.
The photoresist i mentioned is fairly soft and will scrape off.
Have problems with thin non rigid sheet though , metal blunts the cutter and it is difficult th set the depth on anything but a flat board.
Tried on pcb and etched you get a result similar to using a Proxon mill
Have you got to grips with GPGL yet (successor of HPGL.)
Thermal transfer printing has been tried succesfully but suffers from very low resolution.
I wonder if the coatings used for hand engraving of plates may be suitable.
Permanent marker method looks cool but i could not ger it to work.
Maybe ferric chloride is too strong.
In the video though she appears to be using Potassium Persulfate , might be worth another go.
Boardburner2:
Permanent marker method looks cool but i could not ger it to work.
You are much quicker off the mark than I am
When I was trying my electro-etching using self-adhesive vinyl for the mask I did try a corner of the brass with nail polish and permanent marker and they both protected the metal. I have never tried using ferric chloride.
Presumably one could paint over the metal surface with an etch-resist pen and then scratch through that?
What were you using that caused the problem "it is difficult th set the depth on anything but a flat board."?
In the video the scriber seems to have a lot of movement to allow for an uneven surface.
I would not use a blade that I was worried about blunting. I don't yet have a pen holder for my Silhouette Portrait but I think it may be possible to mount a scriber in a pen holder.
Robin2:
What were you using that caused the problem "it is difficult th set the depth on anything but a flat board."?
In the video the scriber seems to have a lot of movement to allow for an uneven surface.
...R
Thin brass fed through my silouette.
Needed a blade to cut the etch resist as a point just tore a ragged line, setting the cutter depth right proved tricky..
I think because of flexing in the brass.
Maybe i did not have the 'right sort' of permanent marker.
I did not have the silouette when i tried the marker so i may have another go with a stylus in place of the cutter.
What worries me is that the roller mechanism may scratch the marker.
Boardburner2:
What worries me is that the roller mechanism may scratch the marker.
I'm thinking of fixing the brass to a piece of card or plasticard with the registration marks printed on it. That would mean (with my Portrait) that the drive rollers would not be in contact with the brass. There are too soft "rubber band" type rollers nearer the centre but I doubt if they would cause a problem.
The reason for the registration marks is that I want to do double-sided etching and would need some means to position the brass accurately.
One of the reasons I have not jumped to try this on my Portrait is doubts about how to scrape a wider path than would be done by the very sharp paper cutting blade. I have read on another Forum where people have deliberately made a square chisel edge on the blade so it would scrape plasticard to give the effect of wooden planks or the mortar between stones. And if you look at the video (an especially some close-ups on the guy's blog) it is clear that his cutter is running along the same path a few times separated by the width of the blade so as to scrape a wider path. I can easily see how 3D printing software could be adapted for that - in fact it is probably a natural feature. But I suspect the software I am using with the Portrait is only designed to identify edges and cut along them. I have not tried to study it yet and it may be necessary to modify it - it's just Python code.
Another reason for dithering (and there are more than 2 reasons ) is that I also have the option of using my small lathe to drive the scriber quite separately from the Portrait. And I could probably use GCode for a 3D printer with that. However the small lathe could not work over such a large area as the Portrait. The max width is about 60mm and the length maybe 130mm or, with some mods, perhaps 200mm. Also it would be very much slower.
I would also like to get (or make) a pen holder for the Portrait so that I could see it draw the shapes on paper without wasting brass.
For some of the other reasons I am unlikely to do any testing this week.
Of course the question of whether permanent marker (or some sort of spray paint) could be used in this way can easily be proved with the point of a nail held in one's hand
Robin2:
As far as I know it does and with either an ink-jet or laser printer. But I am hoping to avoid photo-resist as it adds another stage to the process (and chemicals).
At the moment the only "chemical" I need is salt water.
...R
What you get out may be toxic from copper content.
Are those buzzy etching tools unsuitable? I am guessing yes.
Of course the question of whether permanent marker (or some sort of spray paint) could be used in this way can easily be proved with the point of a nail held in one's hand
...R
Yup i am off to Sanisburies for some marker pens to give it a go tonight.
As far as dithering goes i think that may be the name of what i want to do.
Newspapers used to print pictures using varying size spots to give a tonal range.
A bit like ascii art.
In what was Staples i saw where you can give them a Photo and they laser etch a 3D image inside a block of glass.
I wondered if it might be possible to make a brass 'Photo' using the newspaper method.
