11 Hand-Made Prototype PCB Guide

 

Laser printouts

·        Top layer — Holes (vias), top copper, outline only

·        Bottom layer — Mirrored Holes (vias), bottom copper, and outline

·        Laser printer (select highest dpi)

·        Take printouts only on Photo papers (for a better-quality heat transfer), magazine laminated papers shall be used

Equipment

·        Fr4 copper board

·        Dry iron without water vapor

·        Surgical sprite or any liquid alcohol

·        Stain removing chemical (Brasso) or sandpaper

·        Low humidity room (for better results)

·        Thin metal single-core wires for aligning (0.5mm gage) — alternatives — metal wire of resistors or 0.3mm gauge coil wires

·        Double side PCB — vias — 0.7mm coil wires (coating should be removed cleaned)

·        Hand drill — Dremel and drill

·        drill bits 0.3mm /0.7mm

Process

·        Cut the required size of copper board

·        Clean the copper board both sides using Brasso, all the stains should be removed

·        Cut laser printed photo paper

·        Clean the copper board with alcohol before start heat transfer, before pacing printout on copper board

·        Take a printout of one side only (prefer top side first)

·        Place laser printout on copper board

·        Heat transfer should be started immediately after taking the printout — otherwise, the humidity will damage the quality of the heat transfer process

·        Heat transfer for 10min 15min

·        During ironing do not pat photo paper to slip or move on the copper board, hold it until it gets to stick with the PCB board

·        Heat transferring more than 15 min will damage the printout — damages transferred tonner — damages copper paths in the PCB board

·        Clean the PCB — use water to wet the sticked photo paper, use a smooth brush to the pill of the paper, do this carefully otherwise tonner will come off from the PCB board

·        Small tonner damaged areas can be repaired with a permeant marker- not recommended for complex PCBs with many damaged areas — redo the process if you have messed up

·        For double-sided PCBs — make 3 holes (0.5mm/ 0.3mm or less) for aligning if holes are bigger the PCB will misalign — go for random places on PCB — ( eg- not square- random places will align the PCB properly)

·        Take a printout of the other side (mirrored bottom side)

·        Place bottom side mirrored print out on the other side of the copper board

·        Make the same three holes on bottom side printout

·        Use 0.3mm/0.5mm metal wires for aligning

·        Heat transfer for 10min 15min

·        Do not let PCB boardslide on the surface, transferred tonner on the other side (top side layout) will damage

·        Clean the PCB — use water to wet the sticked photo paper, use a smooth bush to peel off the wet photo paper, do this carefully otherwise tonner will come off from the PCB board

·        Use ferric chloride for etching — hot water — speedups the process

·        Room temperature water also fine

·        Use ferric chloride powder- this speed up the process

·        Don’t use stiffed ferric chloride — it is not soluble in water

·        Don’t breathe the smoke comes during the etching process — this is harmful chlorine gas

·        Once all the unwanted copper is etched PCB is ready for soldering.