This is an old revision of the document!
pcb creation
this doc aims to explain how to make pcbs using the photo etching method on uv sensitive boards
kit list
- acetate (we have)
- az303 developer (we have)
- uv light box (we have)
- bubble etch tank (we have)
- ferric chloride 40% premixed (we have)
- a timer (attached with magnet to shelves above the bubble tank)
printing
using eagle
- show the layers you need. I used top, pads, vias and dimension for a combo SMT and through hole board
- print from eagle to laser printer, click the mirror and black box
- acetate face down in laser printer
- make sure the print is black enough or you will have problems with the resist - you can try printing twice
exposure
- if you've had to cut the board down, make sure it's flat with a file or you may get uv leaking under the acetate
- peel off protective cover on the board
- line up the artwork on the board. You may want to hold it in place with tape
- make sure it's the right way round!
- put the board down on the uv lightbox glass with the acetate between
- set timer for 1.5 minutes, press go
problems
- If you see pitting in the resultant mask it's because you exposed for too long or the acetate wasn't dark enough
developer
we don't have a slot for this in the etch tank so we do it in a shallow tray
- put the board in a shallow tray
- cover with the developer
- leave for 2 minutes
- wipe off developed mask and rinse in water
etching
- turn on the tank and the heater
- set the thermostat to 4 and wait for heater lamp to go out
- put board in the mesh holder and immerse in the ferric chloride
- turn on the bubble pump
- wait for until etching is complete (at least 3 minutes). timings vary on size of board, temperature and as ferric chloride is used.
- clean off the mask with acetone
- resources/bubble-etch.1434400586
- Last modified: 6 years ago
- by mattvenn