Hi, In recent years Centari has basically eliminated the recommendation for flash times between coats. It used to be 5-10 minutes like most other enamels. What it means is that as soon as you are done with the first coat, you can immediately begin the next one. No waiting between coats. I take that with a certain amount of caution. Centari is a very easy spraying paint that is difficult to run. However, there is a difference between painting an entire car and painting a small tractor part, such as an air cleaner. For smaller parts, I still give it a few minutes between coats - it does no harm. Don't forget that for a large part or an entire car, there is a certain amount of flash time automatically built in to the procedure. That's the time it takes to complete one coat. You don't get that with a small part. A cross coat technique is also recommended. That means the follow coat passes are applied 90 degrees to the previous coat passes. I do that on the larger, broad parts such as a car hood, but don't bother with it on the smaller ones. I think you are doing it about right. There is no need to begin the first coat with a "tack coat" as was typical with the old alkyd slow dry enamels. Start right off with a full coat that essentially results in complete coverage. It's tempting to stop after the second coat because of the good coverage but I always go ahead and apply a third. For good measure if nothing else. I don't know which field mix version of Centari you are using. There are three different ones: Centari with Ultra Performance Pak, Centari with 793S hardener and Centari with Ultra 1K Pak. The minimum 4 hour recoat period applies to the later two mixes. There is no stated minimum recoat period for the first mix. Do not confuse the recoat period with flash time. Recoat refers to applying more paint after the first coat(s) have had a chance to dry a considerable amount. There is a chance of wrinkling of the paint film if additional paint is applied before that recoat time has elapsed. A 4 hour minimum recoat period is a very short time as far as I'm concerned. It used to be measured in days in the past - and may still be with some paints if a hardener is not used, depending on how agressive the reducers are. DuPont says the 4 hours is safe. It won't do any harm if you exceed that as a precaution. If you go beyond 24 hours though, I'd consider a light scuffing with Scotch-Brite before applying more paint. That's specifically recommended for the first field mix mentioned above. It's not stated for the other two. Centari is an excellent acrylic enamel, as is Delstar in the PPG line (if you can find Delstar and care to pay the price). Centari is similarly expensive. I recommend using Centari with the Ultra Performance Pak, if you haven't already done so. I consider it the best of the three available field mixes. The only one that is iso-free is the Ultra 1K Pak mix. If you are getting a bit of orange peel, try using the next slower reducer listed for the temperature at the time of spraying. Also make sure that your air pressure is adjusted correctly at the gun. Additionally, If you are doing an entire chassis at one time, follow the zero flash time recommendation and apply the second coat as soon a possible and in the same shooting sequence. Have enough paint mixed up before hand for all the coats so as to avoid taking time out to mix more in the middle of the process. Rod
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