I‘m interested in building a solar water heater for my home and I‘m searching for the best materials with which to work.
copper and aluminum are two of the best
maybe you have some grit or a stone in your wheel? mine had that and made a weird whining noise but went after a few weeks :P
sounds like a wheel bearing
your brake pads are going, you need to replace them just take your car to a garage or something and they will do it for you
Copper tubing is readily available, and easy to work with because you can solder it with plumber's solder. For the box that holds the tubing, I'm not sure it matters so much how conductive it is. What would matter is how well sealed it is against drafts, and how well insulated on the outside. I would just use something like galvanized steel, and paint the inside black with roofer's spray paint, you know, the kind they use to paint metal roof flashings.
