From b32a16494f129602d32a0e1493849b0fd97a0615 Mon Sep 17 00:00:00 2001 From: Mark van Renswoude Date: Wed, 7 Nov 2018 22:37:39 +0100 Subject: [PATCH] Updated bom (markdown) --- electronics/bom.md | 43 +++++++++++++++++++++++++++++++++++++------ 1 file changed, 37 insertions(+), 6 deletions(-) diff --git a/electronics/bom.md b/electronics/bom.md index 2a09186..1d5f652 100644 --- a/electronics/bom.md +++ b/electronics/bom.md @@ -4,24 +4,55 @@ [[_TOC_]] - -#### Laminator +## Tools +### Laminator Some household laminators will do, just be sure it supports the extra thickness of a circuit board and possibly cardboard to help it along. I got a generic A3 laminator from AliExpress which has a temperature setting and adjustable springs. It has no brand name, but if you search for "A3 laminator" it's the one that looks like this: [[bom/laminator.jpg|width=400px]] -#### Printer +### Printer Many people use a laser printer, but the ones I had did not deposit enough toner to work all that well. For an inkjet printer the best results are achieved with inks based on pigments instead of dyes. The printer I use is a Canon PIXMA iP7250, which is not all that expensive. For any Canon use the official "PGI" range or cartridges, as these are pigment based. With these I do not need to double up on transparencies to get great results. -#### Transparencies +## Consumables +### Transparencies Use transparencies designed for your printer type. The ones I use are Esselte 57161. -#### Circuit board +http://www.123inkt.nl/Esselte-57161-transparanten-voor-inkjet-printers-50-bladen-57161-i22534-t33400.html + +### Circuit board I don't use boards with a presensitized photoresist layer, so any plain single or double sided board will do. Don't get the cheap cardboard ones though. Adding the film yourself is a bit of extra work, but allows you to retry if the exposure fails. Replacing the film is a lot cheaper than wasting copper. -#### Photosensitive film +### Photosensitive film Search eBay for "photosensitive dry film PCB". The rolls are blue and typically come in 30cm x 5m. + +### UV curable solder mask (optional) +UV curable paint which can be used to create a solder mask. +The set I got comes in little syringe tubes in various colours and were ordered from AliExpress. + + +## Chemicals +Note: I forgot most of my chemistry lessons, so any chemist will probably yell at me for getting the mixes all wrong. They are not accurate by a long stretch. They are however good enough to work well for my purpose. + +### Sodium metasilicate +Used to develop the photosensitive film. The recommended solution is 4,8%. + +Purchased as a 37% solution:
+https://www.deoplosmiddelspecialist.nl/kopen/natriumsilicaat-glaswater + +Added 100 ml of the sodium metasilicate solution to 750 ml of demineralised water. + +### Ferric chloride +Used to do the actual etching. You can get it in solid form and dilute it yourself, but since I don't use that much I just get it premixed to 40% in 1 liter bottles, which can be used straight up: +https://www.deoplosmiddelspecialist.nl/kopen/Ijzerchloride-40-1L + +### Sodium hydroxide +Used to remove the remaining photosensitive film after etching. The recommended solution is 1%. + +Purchased as a 10% solution:
+https://www.deoplosmiddelspecialist.nl/kopen/Natronloog10 + +Added 100 ml of the sodium hydroxide solution to 900 ml of demineralised water. \ No newline at end of file