how much for change water pipe into copper?
You don't want to do that. The new plastics are 100% more reliable and easier to add too and repair. If it aint broke, don't fix it.
They run cooler, they are less affected by dirt ( especially usefully for grinders) since they are pressurized by the, presumably filtered, air that powers them, while electric motors usually have to be cooled with the ambient air, often blown directly through the motor. They tend to last longer (for the above reasons) In areas where electrical shock could be a hazard, the lack of electricity is an obvious advantage. In many cases they are smaller and lighter than equivalent electrically powered tools. On the other hand, it can take a 5 horsepower or so compressor to run pneumatic die grinder roughly equivalent to a 1/4 horsepower electric one, so there is a trade off.
unless you have very soft water, you don't want to do this. we just had a guy come by to test our water, and he said that copper pipe was the worst to have when you have hard water. I can't remember what he said about it, but you DO NOT want to do this. plus the price of copper has gone up, and yeah, just don't do it. if you want the look, buy some copper spray paint and spray paint whatever you decide to do, if it going to be visible anyway.
I think you want to change lead pipes, and replace them with copper, plastic is cheaper to install, but if in view, copper is more rigid and looks better.
