Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

I bought some of the dry film from the same ebay vendor last month. I have not had any problems with it. Make sure the board is clean. I use Bar Keepers Friend and a scrub brush to clean the board. After cleaning and rinsing, I blow dry the board with a hair dryer and only handle it by the edges.

When laminating the board I work under an orange CFL 13 watt bulb that I bought at Home Depot. The brand name is Feit and I have it about 4 feet from my work area.

I have a Scotch TL901 laminator that I use for laminating the board. I put it on the 5 mil setting which is the highest heat. I pass the board through the laminator once, flip it over, and pass it through a second time. By then the board is pretty warm (almost too hot to hold).

I have four FT15T8/BL bulbs mounted in a wooden frame. I expose the board at a distance of 4 inces from the bulbs for 2 minutes. I then let the board sit for 15 minutes before developing. My developing solution is 100% sodium carbonate that I bought at a pool supply house. The name on the container is Pool Season and the product name is pH UP. The ratio is the 20g/L mentioned above. The developer is heated to around 90 degrees F for best results.

I picked up my process from this site: http://www.thinktink.com. They have several tutorials on their site that were very helpful in getting my process down to where it is alway 100% reliable.

Ray