After about 3 pots of sand we noticed we were blowing a lot of sand and no paint was coming off, and the pressure in the pot was dropping uncontrollably. We looked everything over and found this. The nozzle, which is attached to the hose, had a leak. Over time, the sand blasting out that leak wore away the feed to the nozzle, until there was such a large leak that we couldn't keep pressure up, causing sand to just dump out, not enough pressure to get the abrasive quality we need...