The printed circuit is made of epoxy resin or fiberglass , lined with a thin layer of copper on one or both sides and covered with a photo-sensitive varnish. The lacquer layer protects the copper is irradiated, by imagewise transfer…
A good chair is important and over the years I’ve learned that not all chairs are made equal. I’ve bought inexpensive chairs and I’ve bought pricey ones and none of them lasted more than a little over a year for…