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September 2017

What’s In A Board?

There are plenty of high quality, double-sided printed prototyping boards readily available on eBay. They are perfect if used as they are, unless — as it often happens — the need arises to trim, grind, or otherwise shape them.

Here is my problem: I am deeply concerned that these boards are made with asbestos. I know that for any grinding job a facial mask is a must, but if the dust created in the process could contain asbestos particles, much stronger protection measures would be warranted. Or, perhaps such operations should be entirely avoided.

I imagine that many electronics enthusiasts cut or even grind these items, completely unaware of the danger they may pose. I tried to gather information from the Web about these products, with little success.

I would like to know — preferably from an authoritative source — what materials are used in production of these (mostly Chinese in origin) prototyping boards.

#9171
Jan Raj
Philadelphia, PA



Answers

The substrate of most of these boards will be made of FR4 or G10. Both of these are glass epoxy laminates. Some less popular substrates include phenolic or even aluminum.

In addition to the substrate there is copper (obviously), plus solder mask and silkscreen. The solder mask and silkscreen are often made of lacquer or epoxy-based inks. As far as I know asbestos is not used in the production of PCB’s.

It’s good that you’re concerned about personal protection, though. The glass fibers that are released when cutting these boards can still be hazardous, and personal protective equipment is always a good idea.

Rick Curl
Pinson, AL

It’s unlikely you’ll find asbestos in circuit-board material. Most are fiberglass and epoxy. Still, you don’t want to breathe fiberglass dust when you cut a board. A dust mask and safety glasses work well to keep dust out of lungs and eyes.

Most often I use a sharp box cutter or an X-acto knife to score the PCB and then snap the sections apart. The knife doesn’t need to cut all the way through a piece of board. A small coping saw with a fine-tooth blade would also work.

Also look at jeweler’s saws that come with fine-tooth blades. You’ll need a vise or a clamp to hold the PCB steady for sawing.

Jon Titus
Herriman, UT

I have worked with electronics for about 50 years, and with circuit board design for about 30 years. I have never even heard of a circuit board made with any asbestos. Most circuit board material is FR-4, which is glass epoxy — that is, fiberglass. It is usually 0.0625” (1/16th) inch thick.

When cutting or sanding circuit boards you should wear breathing protection — some kind of dust mask — as the dust created by cutting the fiberglass board is hazardous.

You can see more info on circuit board materials here, https://en.wikipedia.org/wiki/Printed_circuit_board.

Stan
West Hills

I cannot say for all boards, but the ones I see usually specify FR4 fiberglass, which is asbestos-free. Of course, grinding fiberglass isn’t ideal either; you should always wear breathing protection while grinding ANY PCB since the dust isn’t the best thing in the world to breathe.

Ralph Phillips
Bossier City, LA

A "proper" PC board is made from epoxy resin with a fiberglass filler or from phenolic resin with paper filler. Any of this stuff would be better if you didn't breathe it, but it's not asbestos. One way to minimize the problem is to cut the fiberglass board with tin snips. That makes little to no dust.

Chip Veres
Miami, FL

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