I think you can use any container (avoid transparent to protect your eyes) as long as it is not too deep or you will have to expose longer.
I have a tablesaw in the room (don't ask) so it was easy to just slap a box together from a piece of scrap chipboard wy wife pitched up at home with... she knows just what kind of stuff I keep my eyes open for always..
I have a tablesaw in the room (don't ask) so it was easy to just slap a box together from a piece of scrap chipboard wy wife pitched up at home with... she knows just what kind of stuff I keep my eyes open for always..
Nordic said:I think you can use any container (avoid transparent to protect your eyes) as long as it is not too deep or you will have to expose longer.
I have a tablesaw in the room (don't ask) so it was easy to just slap a box together from a piece of scrap chipboard wy wife pitched up at home with... she knows just what kind of stuff I keep my eyes open for always..
es44 said:
Respect.... Does she have a sister who's single? You're a lucky man
best regards
Ebbe
does she have two single sisters?
Fellows, the right women are out there... I have one similar...
While dating, before marriage ( ! ) casually mention digging around in a pile of rubbish for the miscellaneous bit of useful stuff...
the reaction is one of the criteria for mate selection (for some of us)
BTW thanks for this thread, I had never thought of the idea, but it's a very good one.
While dating, before marriage ( ! ) casually mention digging around in a pile of rubbish for the miscellaneous bit of useful stuff...
the reaction is one of the criteria for mate selection (for some of us)
BTW thanks for this thread, I had never thought of the idea, but it's a very good one.
For what it's worth...
I have several UV-C (2.54nm wavelength) flourescent lamps made by
Atlantic UV that I bought on e-bay several years ago when I was going
to build a similar project.
However, the Atlantic UV Corporation informed me that UV-C tubes are
actually made out of clear QUARTZ because glass will filter out the short
2.54nm UV wavelength. In other words, making them out of glass tubes
would render them useless. This explains why UV-C bulbs are so damned
expensive.
I was planning to use GLASS to hold the artwork in place over the PCB.
Get it? The plan is flawed because the glass will, in essence, neutralize
the benefits of using UV-C.
However, I see lots of these projects being built, and everyone seems
satisfied with the end results, but if they're using glass to hold the
artwork, how does the UV-C get through? Is the filtered out UV-C beneficial?
How does this make the exposure "better?"
I'm beginning to wonder if people building these projects with glass
are fooled into thinking that UV-C bulbs are the magic bullet, when
it's quite likely that regular soft-white, or perhaps UV-B (blacklight)
would provide the exact same results, maybe even better.
UV-C and glass... the new snake oil??? Next we'll be having debates
as to whether PCB's exposed with UV-C rays "sound better."
Anyone care to share their thoughts on this?
(Sorry if my post seems repetitive. I'm fighting a killer headache which
adversely affects my concentration.)
I have several UV-C (2.54nm wavelength) flourescent lamps made by
Atlantic UV that I bought on e-bay several years ago when I was going
to build a similar project.
However, the Atlantic UV Corporation informed me that UV-C tubes are
actually made out of clear QUARTZ because glass will filter out the short
2.54nm UV wavelength. In other words, making them out of glass tubes
would render them useless. This explains why UV-C bulbs are so damned
expensive.
I was planning to use GLASS to hold the artwork in place over the PCB.
Get it? The plan is flawed because the glass will, in essence, neutralize
the benefits of using UV-C.
However, I see lots of these projects being built, and everyone seems
satisfied with the end results, but if they're using glass to hold the
artwork, how does the UV-C get through? Is the filtered out UV-C beneficial?
How does this make the exposure "better?"
I'm beginning to wonder if people building these projects with glass
are fooled into thinking that UV-C bulbs are the magic bullet, when
it's quite likely that regular soft-white, or perhaps UV-B (blacklight)
would provide the exact same results, maybe even better.
UV-C and glass... the new snake oil??? Next we'll be having debates
as to whether PCB's exposed with UV-C rays "sound better."
Anyone care to share their thoughts on this?
(Sorry if my post seems repetitive. I'm fighting a killer headache which
adversely affects my concentration.)
you don't need that much UV. those UV lamps are also called "germicidal lamps" which have the harmful UV output. glass blocks this UV which (I'm not sure if it will make it safer) isn't actually needed in photoetching.....well, not that much UV though.
I'm using ordinary flourescent lamps for this purpose and it works well so a little UV is enough......
I'm using ordinary flourescent lamps for this purpose and it works well so a little UV is enough......
It al depends on the duty cycle... but a 9v batery operated exposure box would be worth haveing to wait 4 minutes for if it was a 50% cycle...
I'm speaking under correction but I think it was strobing at 270 something times per second....which I don't think allows it to reach a fully off state during use...
I'm speaking under correction but I think it was strobing at 270 something times per second....which I don't think allows it to reach a fully off state during use...
Nordic said:
LEDs switch so fast 270Hz is nothing. One thing pulsing allows is much higher forward current, giving more range in signalling applications (and from a torch beam). Though to keep temperature down the average current can never be better than that from a continuous supply.
There are a number of circuits around using a battery-powered LC oscillator supply, a big plus is they allow the battery to run almost flat and still produce light. See this Joule Thief.
Type 'C' UV is shortwave (below 280nm) and most dangerous; kills bugs but also causes skin cancers, blindness. Ordinary window glass will block 90% but pass 90% of relatively harmless UVA.
Finaly got to test it on a larger pice of PCB, had to increase the distance to the board by about 1cm to get better overlap, but all's well that ends well...
The funny colour is a combination, of photopositive not being removed yet, andthe infrared light from my webcam...
So there for those who doubted it...
No idea what the partnumber was... was from cheapy local electronics shop, so just about any uv led should work... you can always just buy one first and test it on some photoresist at home... If you have a choice getting one with wider angle beam, might make it possible to get more even lighting at closer distances...
The beam angle would affect the distance to the pcb to some extent, mine is about 4" (10cm), I started mounting the leds at the full length of their legs, and then moved them back in the pcb, to get better results with larger PCB pieces (obviously it takes a minute or so longer exposure if you increase te distance- don't think overexposure is ever going to be a problem, so you could even try leaving it on 5 o 10 minutes, if first attempts don't come out 100%... it did take me a few tries never haveing done photoetching before... so easyto go wrong with the damn chemicals - then you need to clean the PCB and start over..
The beam angle would affect the distance to the pcb to some extent, mine is about 4" (10cm), I started mounting the leds at the full length of their legs, and then moved them back in the pcb, to get better results with larger PCB pieces (obviously it takes a minute or so longer exposure if you increase te distance- don't think overexposure is ever going to be a problem, so you could even try leaving it on 5 o 10 minutes, if first attempts don't come out 100%... it did take me a few tries never haveing done photoetching before... so easyto go wrong with the damn chemicals - then you need to clean the PCB and start over..
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