Building a UV PCB exposure box?

Started by April 6, 2007
"Aly" <,shfskfjsf@sliuflky4iuhdf.erl> wrote in message
news:YJ6dnVGYZuF3h4vbnZ2dnUVZ8qqlnZ2d@bt.com...
> Hello, >
<SNIP>
>
Thank you to those who are replying. I'm following with interest. At the moment I'm swaying towards the &#2013266083;100 for sake of ease. Oh, printer, photo inkjet, transparances, Brother DCP-340CW apparently 1200x6000dpi... we'll see about that. :-) Aly Aly :-)
On 6 Apr, 11:05, "Aly" <,shfskf...@sliuflky4iuhdf.erl> wrote:
> Hello, > > Ideas please? > > A small professional UV box with two 8W tubes will cost about =A3100, and=
is,
> professionally made and neat and tidy. I'm wondering if for sake of ease=
it
> would be easier to just go out and buy one? > > I've seen the UV "fly killer," tubes on eBay for say =A310, which are > mentioned in a few of the tutorials online. Ballasts I have at home > somewhere. Would need a neat little case, cut glass, switches, bits bobs, > and time. > > This is all purely for making the odd PCB so nothing commercial. There's > also those little UV nail boxes for curing the plastic, they're only about > =A320 although I wonder about even coverage with those, and if indeed it =
is
> the right type of UV? > > Circular tubes? U-shaped tubes? Straight tubes? Little 9W dual parallel > tubes? > > I'm just wondering in the end if it would be easier to just buy one, > although that's not really in keeping with the spirit of diy. > > Many thanks for any input, I'm just looking for ideas and opinons really. > I'd also be half tempted to put in regular tubes too so that it can be us=
ed
> as a light box. > > Friendly regards, > > Alison > > ps. There's this one at Rapid for =A3110 in a little kit; > > <http://www.rapidonline.com/searchresults.aspx?style=3D0&kw=3D34-0690>
I built one using two UV tubes in standard 12" fluorescent fittings, with a box made from MDF and a sheet of glass. It cost me about 20 GBP. Leon
On 6 Apr, 12:03, "larwe" <zwsdot...@gmail.com> wrote:
> On Apr 6, 6:05 am, "Aly" <,shfskf...@sliuflky4iuhdf.erl> wrote: > > > somewhere. Would need a neat little case, cut glass, switches, bits bobs, > > You need _quartz_ glass to pass all UV. Apart from this issue, all the > mechanical needs are satisfied by taking an old scanner and removing > the innards; put the UV tubes and reflector inside where the scan > mechanism used to go, and put your PCB on the glass, then close the > lid. > > > Many thanks for any input, I'm just looking for ideas and opinons really. > > I'd also be half tempted to put in regular tubes too so that it can be used > > as a light box. > > Not advisable. If you're building a UV box, you should interlock it so > that the tubes cannot come on while the lid is open. There are fun > ways of going blind, and dumb ways... stick to the fun ways.
You don't need quartz, ordinary window glass is transparent to the long-wave UV used for PCB exposure. The light isn't particularly hazardous. Leon
On 6 Apr, 14:54, "Aly" <,shfskf...@sliuflky4iuhdf.erl> wrote:
> "Aly" <,shfskf...@sliuflky4iuhdf.erl> wrote in message > > news:YJ6dnVGYZuF3h4vbnZ2dnUVZ8qqlnZ2d@bt.com... > > > Hello, > > <SNIP> > > Thank you to those who are replying. I'm following with interest. > > At the moment I'm swaying towards the =A3100 for sake of ease. Oh, print=
er,
> photo inkjet, transparances, Brother DCP-340CW apparently 1200x6000dpi... > we'll see about that. > > :-) Aly > > Aly :-)
I use an HP 5940 printer with JetStar premium film, results are excellent. Leon
On Fri, 6 Apr 2007 11:05:04 +0100, "Aly"
<,shfskfjsf@sliuflky4iuhdf.erl> wrote:

>Hello, > >Ideas please? > >A small professional UV box with two 8W tubes will cost about &#2013266083;100, and
is,
>professionally made and neat and tidy. I'm wondering if for sake of ease it >would be easier to just go out and buy one? > >I've seen the UV "fly killer," tubes on eBay for say &#2013266083;10, which are >mentioned in a few of the tutorials online. Ballasts I have at home >somewhere. Would need a neat little case, cut glass, switches, bits bobs, >and time. > >This is all purely for making the odd PCB so nothing commercial. There's >also those little UV nail boxes for curing the plastic, they're only about >&#2013266083;20 although I wonder about even coverage with those, and if indeed it
is
>the right type of UV? > >Circular tubes? U-shaped tubes? Straight tubes? Little 9W dual parallel >tubes? > >I'm just wondering in the end if it would be easier to just buy one, >although that's not really in keeping with the spirit of diy. > >Many thanks for any input, I'm just looking for ideas and opinons really. >I'd also be half tempted to put in regular tubes too so that it can be used >as a light box. >
I don't use the photo method much anymore, but for many years I did it wifh a UV tanning floodlamp in one of those clamp-on utility lights with a spun aluminum reflector. I'd lay the PCB on a piece of plywood on the floor, with the artwork taped over it and a sheet of ordinary window glass on top to make sure everything was flat. The tanning light was clamped to the back of a chair so it was 2-3 feet from the work, and pointing straight down at the center of the board. True, that plain glass probably blocked some UV, but so what? The tanning flood puts out a ton of it, and you don't really want a super-short exposure here. Several minutes is fine, since it gives you some room to adjust exposure times. Best regards, Bob Masta D A Q A R T A Data AcQuisition And Real-Time Analysis www.daqarta.com Scope, Spectrum, Spectrogram, Signal Generator Science with your sound card!
On Apr 6, 9:09 am, "petrus bitbyter"
<pieterkraltlaatdit...@enditookhccnet.nl> wrote:

> _Quartz_ glass? I was told so very often. But the glas of scanner is > apparently good enough.
It depends on the UV wavelength required for this application, I assumed it was rather short-wave. Below 170nm or so quartz glass is really necessary. Germicidal lamps have a quartz envelope.
On 6 Apr 2007 05:32:44 -0700, "larwe" <zwsdotcom@gmail.com> wrote:

>On Apr 6, 8:28 am, Mike Harrison <m...@whitewing.co.uk> wrote: > >> The type of UV tube used for PCB exposure are not particularly hazardous ( unlike
the germicidal
>> ones used in UV erasers). > >What wavelength is required? I assumed they were the same.
I think germicidal ones are something like 254nm There are 3 types of commonly available UV fluorescent - easily distinguishged by their appearance : Clear glass : germicidal/eprom eraser. Dangerous. Black/dark violet : theatrical/disco - not very good for PCBs White : fly killer/PCB UV exposure
"Aly" <,shfskfjsf@sliuflky4iuhdf.erl> wrote in message
news:YJ6dnVGYZuF3h4vbnZ2dnUVZ8qqlnZ2d@bt.com...
> Hello, >
What nM are we talking about for photoresist exposure? I'm looking at UV LEDs on eBay at the moment. 150mcd, about 400nM. Search for inside the brackets. ( UV "LEDs" ) to weed out the other stuff.
"Aly" <,shfskfjsf@sliuflky4iuhdf.erl> wrote in message 
news:UN6dnbvj9KUl9ovbnZ2dnUVZ8saonZ2d@bt.com...
> "Aly" <,shfskfjsf@sliuflky4iuhdf.erl> wrote in message > news:YJ6dnVGYZuF3h4vbnZ2dnUVZ8qqlnZ2d@bt.com... >> Hello, >> > > What nM are we talking about for photoresist exposure? > > I'm looking at UV LEDs on eBay at the moment. 150mcd, about 400nM. > > Search for inside the brackets. ( UV "LEDs" ) to weed out the other > stuff. >
Not sure they have the intensity needed for etching, youd probably need hundreds of them lol. That said they're fairly cheap.
On 6 Apr, 16:49, "Aly" <,shfskf...@sliuflky4iuhdf.erl> wrote:
> "Aly" <,shfskf...@sliuflky4iuhdf.erl> wrote in message > > news:YJ6dnVGYZuF3h4vbnZ2dnUVZ8qqlnZ2d@bt.com... > > > Hello, > > What nM are we talking about for photoresist exposure? > > I'm looking at UV LEDs on eBay at the moment. 150mcd, about 400nM. > > Search for inside the brackets. ( UV "LEDs" ) to weed out the other stuff.
UV LEDs can work, Elektor mag. had a design a few months ago. Leon