Friday, September 6, 2013

JetFlex Revisited – Ammonia = Better Cleanup

After doing the final preparations for primer this morning, the parts prepared over the last few days were primed with Akzo primer. After doing a disassembly of the HVLP gun followed by a good cleanup, the gun was reassembled for a round of JetFlex.

Another batch of JetFlex was prepared using the same 15% thinning with distilled water as last time. The parts that will show inside the cockpit were then sprayed. This time two light coats were sprayed waiting 15 minutes between coats. The results look OK but I feel there is room for improvement. Think the 1.4 mm spray tip on the HVLP gun is barely big enough for this paint. Unfortunately, the next size larger tip available for the HVLP gun is 1.8 mm which may be too big … but tempted to order one just to see if it makes for a silky smooth finish.

Frequent readers of the DOG Aviation Blog may remember the first time JetFlex was used, distilled water was run through the HVLP gun but basically did little to clean the inside of the gun ... so the equipment cleanup was a bear. After spending a lot of time cleaning, it was discovered the JetFlex application data sheet suggests using a water and ammonia solution for cleanup.

This time, things were done differently. A 50/50 mixture of distilled water and ammonia was prepared prior to painting. The measuring ladle was not left in the air for 5 minutes like last time and was immediately placed in the ammonia solution to soak. It was immediately apparent the cleaning solution actually cuts through the paint. Frankly, I was a bit shocked at how well it worked compared to the plain water used last time.

For this spray session the HVLP gun was not run dry and when the last piece was finally sprayed with JetFlex, the ammonia cleaning solution was immediately run into the gun. This time the gun cleanup was no more difficult than when using solvent based paint … in fact, it may have been easier. The ammonia solution did a splendid job of cleaning the inside of the gun! I also feel not running the spray gun dry also plays a big part in easy cleanup … because JetFlex forms a film almost instantly so if the inside of the gun is kept wet, there is really no film buildup inside the gun to speak of.  That said, the ammonia solution will still cut through the film with just a little elbow grease.

Now that the cleanup issue has been resolved, I’m very pleased with JetFlex but feel there is room for improvement in my spraying skills and/or using a larger spray tip. Think it is time for the DOG Aviation procurement department to acquire a larger tip for the HVLP gun to see if that improves the final product.