Wanted UV light box for PCB exposure - Page 1
Forum section: electronics / general

author: alanb
author_rank: Frequent Contributor
timestamp: November 23, 2012, 09:42:39 am
content: Looking for a very low cost UV light box new or second hand located in UK. I will only be making small boards therefore the exposure area does not need to be much bigger than 100mm square. A timer is not essential.I am considering constructing as an alternative to purchasing if I cant find one cheap enough.

author: ttp
author_rank: Regular Contributor
timestamp: November 23, 2012, 10:54:50 am
content: Have you considered thermotransfer for making PCBs? Lot simpler in my opinion. If you haven't heard about it watch this video

author: alanb
author_rank: Frequent Contributor
timestamp: November 23, 2012, 11:02:15 am
content: I've considered it but came to the conclusion that UV exposure would be better.

author: notsob
author_rank: Frequent Contributor
timestamp: November 23, 2012, 12:54:10 pm
content: If you consider making one , here is a nice DIY as a guidehttp://en.elektronicastynus.be/projects/81/

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: November 23, 2012, 01:53:52 pm
content: DIY is pretty easy - an old scanner (deep and chunky, not slimline) makes a nice ready-made case, some insect killer tubes and standard fluoro ballasts, and a timer from an old microwave oven - ideally one that goes "Ping".

author: peter.mitchell
author_rank: Super Contributor
timestamp: November 23, 2012, 02:11:38 pm
content: Quote from: mikeselectricstuff on November 23, 2012, 01:53:52 pm

author: ptricks
author_rank: Frequent Contributor
timestamp: November 23, 2012, 03:18:33 pm
content: Using the photo method is definitely the way to go so you are on the right track. I would never go back to the toner method now, the difference in the quality is huge. I wanted to see how small I could go with traces at home and I made a board with a grid, spacing is 10 mil between the lines using 6 mil lines and it came out fine.I don't use an exposure box, instead I use a desk lamp, like this one with a 100W equivalent CFL bulb ( I think it uses 20W), exposure takes about 15 minutes max. I place the lamp next to the board and bend the lamp so it is directly over the board facing down. Any CFL bulb will work as they all have UV output and it doesn't take a lot of UV to expose a board.I do not recommend using LED. LED tend to have hot points in the output lighting and you can't really get even exposure that way.

author: T4P
author_rank: Super Contributor
timestamp: November 23, 2012, 04:45:58 pm
content: Lots and lots of high UV tubes from china, if you're willing to search

author: Dago
author_rank: Frequent Contributor
timestamp: November 23, 2012, 05:27:00 pm
content: You do not need an UV lamp really unless you're in a hurry. I've been exposing my boards with an 11W fluorescent tube desk lamp and it works perfectly. Exposure time is around 12 minutes with a thin plate of glass from an Ikea picture frame.

author: Zero999
author_rank: Super Contributor
timestamp: November 23, 2012, 06:04:34 pm
content: You can buy UV CFLs - even Maplin sell them.

author: nukie
author_rank: Frequent Contributor
timestamp: November 29, 2012, 10:16:27 pm
content: Ladies fingernail polish UV fluoro will work cheap plenty around.

author: miceuz
author_rank: Frequent Contributor
timestamp: November 29, 2012, 11:15:29 pm
content: I've ended up buying a couple of cheap UV money testing rigs, tearing them apart and putting into a drawer.