12-23-2015, 02:02 PM
I have two projects where I need to apply a very nice painted finish. Many paint primers and topcoats have a lot higher viscosity than clear coats. My prior experience with paint told me I needed a new spray gun to do the kind of job I wanted to do. Researching spray guns has to be one of the most confusing undertakings you can do as a woodworker. Nearly no one says "If you want to spray this, use this.". I seriously considered buying a 3M Accuspray gun with replaceable nozzles because it would so easy to clean. Some people thought they spray great, others said they had problems. I also seriously considered the 3M PPS spray cups because of it's ease of cleaning and the fact that you can spray at any angle with it, including upside down. In the end, I did what I should have done in the beginning. I called Jeff Jewitt at Homestead Finishing and told him what I wanted to spray. He immediately said "Oh, you need an AM Smartpak gun." It's a pressurized bottom cup gun that he claims can spray anything from shellac and lacquer up to latex paint. I ended up buying the AM-6008/PPS, which uses a 30 oz pressurized PPS cup. I bought the HVLP gun because my compressor can easily supply the 10 CFM it needs. For smaller compressors he offers a LVLP version.
I ordered the gun on Monday AM and it arrived on Tuesday AM. Talk about great service. The gun is packed in a nice padded plastic case, and contains 3 needles and nozzles, 3 air caps, a spare parts kit, and a cleaning brush and wrench.
Jeff includes are very well written set of instructions with the gun. 3M's PPS documentation was included with their cup, too.
The PPS cup system consists of a rigid outer cup and retaining ring, and an inner, replaceable flexible cup and cap with integral filter.
Here is the gun loaded with Sealcoat shellac. There are two pressure regulators. The one closest to the gun, included with the kit, controls the pressure to the PPS cup; you'll see a hose going from that regulator to the bottom of the cup. It's adjustable up to 10 psi, but you basically just set it at 5 psi for most materials. The lower regulator, not included with the kit, is used to set the inlet air pressure to the gun. With this gun you normally set it at 29 psi. The PPS cup attaches to the gun by pushing the gun adapter tube down over the filter cap and turning 1/4 turn to lock it in place.
After filling the cup and attaching it to the gun, you pull the trigger to pressurize the cup. That collapses the flexible inner cup and forces fluid up into the gun. When the gun starts to spray you are ready to go.
I used the 1.1 mm needle and nozzle to spray the Sealcoat. The flow and pattern were easy to adjust with the two control knobs, following Jeff's instructions, and I had no trouble spraying my drawer boxes. When that was dry I switched to EnduroVar and the 1.3 mm needle/nozzle set and top coated the drawers. EnduroVar has not been that easy for me to spray with my gravity feed HVLP guns, but it was easy peasy with this gun. I got very uniform coverage and very little to no orange peel.
OK, I was feeling good, but now the real test. Paint. I needed to prime and paint a laboratory cabinet and drawer faces I've been working on. I bought BIN Shellac primer and GF's Enduro White Poly for it. The product data sheet for the BIN said the viscosity was 60 KU, which is about 74 seconds through a #4 Ford cup, but I measured only 25 - 30 seconds. Curious. So, at that low measured viscosity I used the 1.1 needle/nozzle set and it sprayed fantastic. The photos are poor, but hopefully will give you some idea of how good it came out. Absolutely uniform with no orange peel, runs, sags, etc.
I sprayed two coats, sanding lightly in between to knock off the whiskers, and filling a couple of pin holes. It's silky smooth now and ready for top coating when the Enduro Pigmented Poly arrives.
Clean up was very simple with the PPS cup. The outer cup never sees liquid so the only clean up is wipe off any overspray. You can clean out the flexible cup or dispose of it. I'm cheap, so I cleaned it out which was pretty simple. I just doused it with ammonia and then soapy water. The gun, however, is no different than most others and required a near complete break down to get all the BIN out of it. This is where the 3M Accuspray gun would have an advantage. But the Qualspray gun sprays beautifully so I'm not complaining.
I hope this little review might be of use to others trying to sort through the maze of spray gun options. I think this gun is going to be my preferred setup for most everything I spray. I'll report back how it worked on the Enduro Pigmented Poly, which is supposed to be around 65 seconds viscosity.
John
I ordered the gun on Monday AM and it arrived on Tuesday AM. Talk about great service. The gun is packed in a nice padded plastic case, and contains 3 needles and nozzles, 3 air caps, a spare parts kit, and a cleaning brush and wrench.
Jeff includes are very well written set of instructions with the gun. 3M's PPS documentation was included with their cup, too.
The PPS cup system consists of a rigid outer cup and retaining ring, and an inner, replaceable flexible cup and cap with integral filter.
Here is the gun loaded with Sealcoat shellac. There are two pressure regulators. The one closest to the gun, included with the kit, controls the pressure to the PPS cup; you'll see a hose going from that regulator to the bottom of the cup. It's adjustable up to 10 psi, but you basically just set it at 5 psi for most materials. The lower regulator, not included with the kit, is used to set the inlet air pressure to the gun. With this gun you normally set it at 29 psi. The PPS cup attaches to the gun by pushing the gun adapter tube down over the filter cap and turning 1/4 turn to lock it in place.
After filling the cup and attaching it to the gun, you pull the trigger to pressurize the cup. That collapses the flexible inner cup and forces fluid up into the gun. When the gun starts to spray you are ready to go.
I used the 1.1 mm needle and nozzle to spray the Sealcoat. The flow and pattern were easy to adjust with the two control knobs, following Jeff's instructions, and I had no trouble spraying my drawer boxes. When that was dry I switched to EnduroVar and the 1.3 mm needle/nozzle set and top coated the drawers. EnduroVar has not been that easy for me to spray with my gravity feed HVLP guns, but it was easy peasy with this gun. I got very uniform coverage and very little to no orange peel.
OK, I was feeling good, but now the real test. Paint. I needed to prime and paint a laboratory cabinet and drawer faces I've been working on. I bought BIN Shellac primer and GF's Enduro White Poly for it. The product data sheet for the BIN said the viscosity was 60 KU, which is about 74 seconds through a #4 Ford cup, but I measured only 25 - 30 seconds. Curious. So, at that low measured viscosity I used the 1.1 needle/nozzle set and it sprayed fantastic. The photos are poor, but hopefully will give you some idea of how good it came out. Absolutely uniform with no orange peel, runs, sags, etc.
I sprayed two coats, sanding lightly in between to knock off the whiskers, and filling a couple of pin holes. It's silky smooth now and ready for top coating when the Enduro Pigmented Poly arrives.
Clean up was very simple with the PPS cup. The outer cup never sees liquid so the only clean up is wipe off any overspray. You can clean out the flexible cup or dispose of it. I'm cheap, so I cleaned it out which was pretty simple. I just doused it with ammonia and then soapy water. The gun, however, is no different than most others and required a near complete break down to get all the BIN out of it. This is where the 3M Accuspray gun would have an advantage. But the Qualspray gun sprays beautifully so I'm not complaining.
I hope this little review might be of use to others trying to sort through the maze of spray gun options. I think this gun is going to be my preferred setup for most everything I spray. I'll report back how it worked on the Enduro Pigmented Poly, which is supposed to be around 65 seconds viscosity.
John