Replies

1. 
   DonStephan | Jul 19, 2010 07:26pm | #1

   Streaks

   One possibility may be an uneven thickness in the wet coat.  The gun may not be spraying a balanced fan and/or the amount of overlap between passes may not be spot on.  When you spray a coat, is it evenly wet when you finish the last pass?  Over the following five to ten minutes, does it maintain a uniform look as it begins to dry, or do wet and dry lines appear?

   Jeff Jewitt's spraying book is on the market, and it helped me tremendously.

2. 
   ring | Jul 20, 2010 02:30am | #2

   learn the walk

   The trick to doing large surfaces (assuming that your gun is in order) is learning to move like a machine, maintaining a constant distance, angle, and rate of progress.  This means learning a certain deliberate way of walking across the job. 

   It also helps if you do a light coat, then immediately do another light coat at 90° to the previous one.  Your piece is not really very large but even so, if the spray is drying before you get back to the next pass you will have lines where the passes overlap. 

   Practice a bit walking the length of the piece with the gun in position.  Imagine that you are a spraying machine.

   Spray a coat across grain and then immediately another coat the long direction.  You'll get the hang of it.

3. 
   sapwood | Jul 20, 2010 11:05am | #3

   I would suggest that you get a large sheet of mdf and use it to practice spraying. Just as in the other aspects of finishing, one needs to work out their methods and materials on scrap before doing the real thing. You are probably overly concerned with applying too much finish, thus you over compensate and apply too little. By working on a sample board you can see what its like to spray too much by simply doing it. 

4. 
   dlb | Jul 21, 2010 09:42pm | #4

   Thanks to everyone who posted a reply as I have picked up tips from each post. I suspect that my problem is either my compressor or the setting of my gun. I can make 4 to 5 passes leaving a uniform surface of paint on the cabinet before allowing the compressor to build up pressure again. The drop in pressure is not very noticable but I like to have as much pressure as I can.  I do leave a wet edge and the area covered by the 4 - 5 passes looks fine until it dries then I see streaks. I would conclude from the evidence that my gun is not adjusted to deliver a consistenly thick coat of paint over the entire pattern. I have not practiced on a large board but that is something I should try given the nature of the project.

   I'll post again when the project has been completed and tell y'all exactly what the problem was.

   Thanks again for all of the help,

   dlb

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1. 
   dlb | Aug 25, 2010 07:59pm | #5

   The project which started this post is still underway. The homeowner has not sold his current suite of furniture so there is no rush for me to complete the job. However, I need to get it completed as I am sick of seeing buttercup yellow (the color being applied.) I have taken the cabinet to a refinisher's shop where we sanded it to the point were we had a flat (no lines) surface. He then applied a very light coat of paint, allowed it to dry and then repeted the process. So far all is well. We now decided to apply the final coat. But before I tell the rest of the story ... ,

   My analysis of why I had streaks is (1) even though I was spraying early in the a.m. it was hot - near 90 degrees. (2) I would have to wait for my compressor to catch up before continuing spraying. (3) I was attempting to complete the job in one pass (read: apply a heavy coat of paint.) And (4) my technique was not very smooth in its application.

   So, Gerry starts the application of the final coat and everything is going smoothly. Until the bright yellow color started attracting bugs. By the end of the spray, we had 5 bugs stuck on the surface and still do as we are awaiting the paint to dry so we can debug the surface and try again.

   Thanks,

   dlb

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