Replies

1. 
   Kevin | Feb 04, 2007 01:55am | #1

   I have zero experience with bleeder-type guns. But it sounds like something is interferring with the width of your fan causing it to not atomize properly at the edges. Assuming there are air-horns on your air cap I would check and make sure none are blocked with dried material. Or, assuming that your gun is more or less laid out like non-bleeder guns, I would check the baffle behind the nozzle. Make sure that the nozzle is seated properly and tightly and that there is no dried material interferring with either the seating or the path that the air takes from the fan control.

   One of the things that I'm in the habit of doing before I spray anything is to do a quick pattern test on a piece of cardboard or scrap . Anything flat and which will readily change color when wetted with lacquer or whatever you are spraying. This allows me to check that my fan is as wide as I want and especially that the material is spread evenly along the width of the fan. Just a quick pull of the trigger head-on is all you need. Then if it's not as you expected or desired you can diagnose and fix the problem before creating a mess on the actual piece which will then have to be fixed.

   If I detect a problem with the fan I will adjust and then do a more extensive test pattern by laying down a few passes to make sure that it's performing as I need it to, analyzing it with a reflection to see how well the laps melt into each other. Again, this will save you time and effort on fixing problems on the actual piece that you want to paint.

1. 
   user-25198 | Feb 05, 2007 06:01pm | #2

   Thanks Kevin, I've been looking at these things too. I'm sure all my passages are clear, but  I will look them over again in case I missed something. This has been a perfect gun (Accuspray) for 13 years. Used maybe 15 jobs per year. I think I may also focus on the turbine, perhaps it may be losing  air volume. Thanks again for your input.

   Jay Slavec

   Gila River Woodworks

    

    

    

    

    

    

1. 
   Kevin | Feb 05, 2007 08:38pm | #3

   I've got an employer-owned Accuspray 1 quart pressure-feed cupgun (conversion HVLP) at my disposal here at work and I would definitely hate to lose it. I don't use it often, but there are times when nothing else will do. I'm particularly fond of using it to spray water-based materials.  Accuspray definitely makes a top quality product!

   You might try contacting Accuspray and see if they can help you diagnose the problem.

   Does your gun have the plastic replacable needle valve tips? If so then it could be that the existing one has frayed and needs to be replaced.

2. 
   oldusty | Feb 05, 2007 09:16pm | #4

   Hi Gila Rat ,

                     I do not use an hvlp , rather an airless , but when the spray fan looks like yours I check and clean the tip first then the filter in the gun cartridge gets cleaned . With an airless if the pump is not producing enough pressure it will act like you describe as well . If there are any filters check and clean them .

                good  luck          dusty

3. 
   RGJ | Feb 06, 2007 02:53am | #5

   I'm not sure just how your gun works but it may be blowing out the center of your pattern. Most guns have atomization holes located in the center of the air cap and fan shaping holes located in the air horns. Do a trigger pull pointed straight onto a blank piece of paper or cardboard. If it looks like a figure eight then your blowing out the center of the pattern. Adjust your fan shaping until the center fills in. If you have a seperate atomization adjustment then try to lower it's pressure. Material should be dispersed evenly across the surface.

   If the viscosity has changed in the material you are spraying then the gun setup will need to be changed to reflect the viscosity change. Let us know how this works out. I use a Zan Cup sp.? to monitor the viscosity of the material I spray.

   RGJ