I am getting set up to make a compact diameter double action telescopic hydraulic cylinder After researching and contacting far too numerous tubing suppliers to mention on 3 continents I came to the conclusion that the only way to make my prototype is to buy tubing already with the correct honed diameter and deal with the OD's myself due to the cost of having to special order some custom made This means over the next couple of months I will be having to make my own centerless grinder which I plan on being a belt sander with attachments