Hi, Guys. I have completed painting a 5" loco with cellulose (car paint). It was quick and easy and gave a good hard finish.Several members in my club use car paint very successfully and even spray on a fuel proofer which makes the paint go even harder. Everything was fine until during a steaming session the boiler primed. It spouted water and wet steam from the chimney and quickly lowered the water level in the boiler. Soon after I noticed that the paint was blistering and appeared to have softened.What happened? Was there an acid content coming from the chimney which the paint could'n't withstand, or was it just excess heat from the boiler during the priming? I have been rubbing down today and found the paint really hard - I had to use P120 to break up the blisters. So I'm stuck. Should I persist with cellulose (assuming no more priming) or should I revert to enamel? I know enamel can go on top of cellulose safely but it takes a long time to harden.Can anyone give me some guidance? I wont be the first to have hit this problem, I 'm sure. Jon MODEL ENGINEERING DISCUSSION LIST. To UNSUBSCRIBE from this list, send a blank email to, modeleng-request@xxxxxxxxxxxxx with the word "unsubscribe" in the subject line.