Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: Hawaii00000 on February 13, 2009, 08:27:01 PM
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If I painted a home-made pcb, then ironed silkscreen from a laser printer onto the paint (just like when you make a pcb), and coated the entire thing with polyurethane, would it work?
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you dont have any conductive elements...
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I don't think you get the question.
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I think Maltik meant that you would end up covering all of you solder pads if you just covered the whole thing with paint and polyurethane. As long as you don't mind your silkscreen being anything but white that part would probably work. Of course if you wanted a good contrast you could use white paint withe a black silk screen. Though you still have the issue of masking the solder pads to prevent the paint and polyurethane from covering them. An Idea I had but have never tried because I'm yet to make my own board would be to put a little grease or patrolium jelly on the solder pads before painting then once the paint is dry use rubbing alcohol to clean the grease/patrolium jelly off the pads. It would be a long process for a board of any detail.
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What paint would you use? Iron-on transfer happens at over 180 degree Celsius, doesn't paint crack at that temperature? I'm pretty sure my heat gun is supposed to be used for "removing old paint" so heat IS used to remove paint.
Another idea: since you're designing a double-sided PCB, you'll have traces on the side you're going to transfer the silkscreen to. The uneven surface might cause problems with your transfer, like only transferring to the traces (because the iron will not be able to push the paper down to the PCB). Try adding something flexible between the iron and the transfer material, like some cotton cloth (never tried that).
The only kind of silk screen I'd ever bother with for a home made PCB would be basic black lines and text (toner transfer) directly to the PCB. I don't expect my PCBs to last for ever (I have yet to use any of my PCBs for more then 2 weeks :D ). And I haven't tried adding any kind of "silkscreen" to my PCB. I usually design something that resemble silkscreen, I print that and I keep the printout on hand while I'm soldering. If something is worth mentioning on the PCB I just hand-write it with a pen.
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I think Maltik meant that you would end up covering all of you solder pads if you just covered the whole thing with paint and polyurethane.
Well the PCB probably needs to be covered in polyurethane anyway so the copper doesn't corrode. I just need to solder the components on first.
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What paint would you use? Iron-on transfer happens at over 180 degree Celsius, doesn't paint crack at that temperature? I'm pretty sure my heat gun is supposed to be used for "removing old paint" so heat IS used to remove paint.
Can't you buy heat resistant paint?
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http://www.pulsarprofx.com/pcbfx/main_site/pages/direct_etch/the_8min_pcb/the_8min_pcb.html
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Amazing - if the photos are correct.
But for home mades, black toner is quite fine for me - anything more needed, I'll go for Olimex.
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Cool!
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I think Maltik meant that you would end up covering all of you solder pads if you just covered the whole thing with paint and polyurethane. As long as you don't mind your silkscreen being anything but white that part would probably work. Of course if you wanted a good contrast you could use white paint withe a black silk screen. Though you still have the issue of masking the solder pads to prevent the paint and polyurethane from covering them. An Idea I had but have never tried because I'm yet to make my own board would be to put a little grease or patrolium jelly on the solder pads before painting then once the paint is dry use rubbing alcohol to clean the grease/patrolium jelly off the pads. It would be a long process for a board of any detail.
Yes, I have seen many people complain about lack of continuity due to excessive insulation such as polyutherane, hot glue, patrolium jelly, etc... But a think layer should be fine
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[...] But a think layer should be fine
Wheee, mind controlled spraying :P ;D
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How do you usually stop the copper from corroding? Do you just do a thin layer?
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That website I linked you to above mentioned tinning the pads.
Pads are usually tinned with tin, but they offer a $50 bottle of silver for tinning your pads
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A few things:
The guy that mentioned petroleum jelly before painting: That's a great idea. You said it would take a while, but if you made a negative mask you could apply the petro jelly using that in one swipe. Of course, making a negative mask, like a solder paste mask, is not easy either, but I just happen to have a cnc machine that can do it. I might have to try this one.
The pulsarprofx link: I use that system and it works awesome and exactly as described. The green/white foil merges with the toner and sticks to the pcb better, plain toner comes off easier. I just saw those pics again and it gave me an idea. What if you took the solder paste mask from your cad package, printed it to toner, transfered it to pcb and coated with green foil. You just made a protective silkscreen-like layer but with the pads clear. Then, do the same thing with the legend layer and the white foil. That would look really good I would think.