PCB Making Equipment

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We have two methods for making PCB's at HackRVA; toner transfer and photoresist. Toner transfer is the simpler and most common DIY method. Photoresist takes more practice.


PCB Making Equipment

Some of our equipment includes:

  • Laminator for heating board and toner transfer.
  • T-shirt press for heating board and toner transfer.
  • Griddle for heating acid.
  • Dedicated laser jet printer for printing designs on toner transfer paper.
  • Lighting for photoresist image transfer onto copper.
  • Toaster ovens for solder reflow.
  • Shear for cutting copper clad board to size.
  • Dremel Drill Press for drilling through holes.

PCB Making Workstation

We have a PCB making station in the Tech Lab. All the stuff is in the labeled file cabinet. The PCB making workstation is stocked only for toner transfer since that's the more common DIY method.

Supplies

  • Single Sided Copper
  • Double Sided Copper
  • Ferric Chloride Acid
  • Toner Transfer Paper
  • Goggles
  • Nitrile Gloves
  • Sponges
  • Steel Wool
  • Ziplock Bags
  • Containers for Liquids
  • Minerial Spirits
  • Dremel Drill Bits for through-hole drilling

If any supplies are low or you wish to buy stuff for your own stash - here's the ordering sheet: PCB Supplies

Email us at infoAThackrva.org if something needs to be replaced or purchased.

Steps for Etching a PCB with Toner Transfer

There are as many variations on PCB toner transfer as their are people doing it. In general they all involve putting toner onto special paper, transferring that toner to the board with heat, etching the remaining copper away with acid, then cleaning of the remaining toner.

This is the specific steps we recommend for beginners doing smaller (<3"x2") single sided boards.

1) Clean board very very thoroughly with steel wool and a bit of soap. Fine grit sandpaper is also good. The cleanness of the board will directly impact the quality of the finished product.

2) Print the board artwork onto the toner transfer paper. Use the recommended laser printer at the space. It is a good idea to set the printer to its highest quality and heaviest ink settings. Also, printing a test print on a sheet of regular paper - this prevents wasting toner transfer paper if an error in scale or direction has been made. (be aware of the image being flipped or "mirrored" incorrectly).

3) Cut out the toner transfer paper with your image and tape it down on one or two edges to the copper (if needed, cut the copper to the correct size with the shear). The tape will prevent the image from slipping as it is run through the laminator.

4) Run the copper with the toner transfer attached through the laminator several times. 10 to 15 times is probably a good number - in general the copper should be too hot to touch comfortably. In some cases, if not enough heat is happening, using a clothes iron can prep the board for extra heat. This will happen on slightly bigger boards or if the laminator just isn't getting hot enough. To test to see if toner is sticking to the copper, pull up an edge just enough to see if the artwork boarder line is sticking properly.

5) Once the toner paper is sufficiently adhered to the copper, take the copper board with the toner transfer paper still attached and place it into a container of water. (The temperature of the water is not important) Let the board soak - after a while, the paper should become somewhat translucent and lift away from the copper under its own volition leaving the toner image on the copper.

6) Take a small amount of liquid Ferric Chloride acid and put it in a ziplock bag. Put the copper board into the ziplock with the acid and squish it around. Avoid rubbing hard, possibly effecting the toner artwork, but you do need to agitate the acid from time to time. Putting the bag in another container and rocking it back and forth by hand can also work if squishing doesn't seem right. 10-15 minutes is about the right time on a smaller board - though this can vary if you add heat (pancake griddle) or there the board is large or there's an abnormally large amount of copper that must be removed w/r/t board size (filling the board properly on your PCB artwork will typically prevent this).

7) Once the copper has etched away, take out the board and clean off with water. Finally, clean off the toner with minerial spirits or paint thinner to remove the toner that was left over.

That's it - happy board making

Other Stuff for Making PCBs

There are several things that you might do after the PCB has been etched. Here are some of them and the tools that go with it.

  • Cut the PCB down to size using the shear. We have a shear specifically for this purpose.
  • Test the traces out for continuity with a multimeter. If you have broken traces this will detect them (making fatter traces in your artwork will minimize trace breakage as well).
  • Drilling through-holes with the Dremel press. There are several Dremel press tools in the Tech Lab and at least 2 Dremels in the space. There are also Dremel drill bits for this purpose in the PCB Making Workstation with a label.
  • Laser cutter or CNC router for solder-paste stencil. It is possible to make a stencil with these tools.
  • Surface mount solder reflow - this can be completed with the toaster ovens that are designated for this purpose.