Originally Posted by splatee
Well I have not ordered the needle yet. So the recomendation now is to go with a 1.0mm needle? I have never used a spray gun before so is a 1.0mm a bit more "forgiving" for a newbie lol. And the main reason with using the Delta Pearl was I already had a few bottles and I was trying to keep cost down because my current screen was suppose to be the "last" screen made per the wife.
Well, considering the desired "permanence" of the screen, it would seem to be that by reverting backwards to a Pearl that was replaced over 3 years ago is a backward step that will relegate your screen to being less than what is possible...if indeed desirable. Then again, a great many used the Delta Pearl in the past with excellent results, so there is that to take under consideration.
Explaining the Needle thingee.....
It's all about "Droplet Size". a 1.5 mm needle produces a finer mist than the 2.0 needle that comes with Graco or Wagner sprayers. So that means less paint induced texture. Even so, to reduce texture to a minimum using a 1.5 mm needle, it is best to sand the painted surface (...after the 3rd or 4th Duster...) then apply 2 "Finish" Dusters.
I myself do repeated screens, so owning multiple Needles for the Graco is more "normal". As such, recently, after having painted a 145"er using the 1.5 mm needle assembly, and using Silver Fire v2.5 4.0
, because of the improvement in both gain and contrast enhancement, paint texture that was not nearly so apparent became to me intolerable. Tiny bumps created not so much a "dirty look"...such as when metallic particles are observed, but a shadow effect where the outside edges of the bumps were visible from 7'-8' away during bright, panning scenes.
Considering that the entire screen was evenly patterned with these "bumps" (...what were in fact a very slight orange peel effect....) I determined to sand down the offending protrusions using a "Medium Grit" Sanding sponge. Doing so, I could then see how what with the "tops" being leveled out, when I reached the point were the "tops" were completely leveled, the surface took on a completely uniform Silver/Gray.
Last year when I painted upon a 106" Mfg Tab Tensioned Screen, I used a 1.0 mm Needle so I would be certain the coating would mist effectively, and produce the absolute tiniest droplets possible while still allowing enough paint to flow out to produce at least a 8" - 9" tall spray pattern. Even so, thinning was essential, to the point where almost no "pooling" within the Sock Strainer occurred....and the number of Duster coats increased by 3 up into the 7-8 category.
But those thin coats dried really quickly when a fan was employed (20-25 minutes) so a complete job was accomplished in just over 3.5 hours time. The end result then was a surface devoid of "ANY" observable texture.
For those with a Graco, you could first use the stock needle for 3 "Light" Dusters, then let the surface dry overnight to a "Bone Dry" point. Then sand the paint down to flatten texture (....but not so much as to remove "color"...) and then changing out the needle to a 1.5 mm or 1.0 mm, apply 3-4 additional Dusters with 70% overlap to achieve a ultra smooth finish.
With my most recent screen, I used a 1.5 mm tip initially, with 5 Dusters, and got the unwanted texture issues because texture is cumulative, and the rolled on primer below was not sanded due to time restraints (...and a bit of frustration with having to make a "screen wise' repair...) so in effect, that was my "Bad". Yeah....I do 'em too, but if they occur, I own up to them and relate 'em so others will not suffer the same torment.
Had I aggressively sanded the primed drywall, the 1.5 mm needle almost certainly would have worked fine, because the paint would have flowed together and dried "Flattened out" instead of simply coating the existing rolled texture.....building up over those existing bumps, and highlighting that texture.
When I use Sintra or any other perfectly smooth surface that requires no priming, of course almost all of the above is moot. But all the same, if one gets to a point in painting and the surface does in fact show a degree of uneven texture, sanding the surface down a bit before continuing will go very far toward eliminating such.
Lastly, the 1.0 mm needle is simply a dead-to-rights assurance that it will be almost impossible to get any degree of texture. It also greatly lessens the possibility of Runs i9f one observes proper Dusting technique and DOES NOT
try to hasten things along by moving slower across the surface that recommended. Then again so does using the 1.5 mm needle, to a greater extent than the 2.0 mm assembly.
It can be a bit difficult deciding what advice to dispense, determining what I can and often do myself, and what to expect from DIY'ers. While I don't mind and can easily justify purchasing whatever I feel is needed, and redoing a surface if my own personal goals are not met, others have both time and budgetary restraints to consider....not to mention even more of an issue as far as patience.
All that said, I still want more than anything else for anyone who makes the attempt to nail down optimal results. It is what drives me to post as often and as much as I do, (...and drives the Wife to....well I'll abstain from that description...) so if and when i change a method or offer up a different take, all can be assured it comes from both experience and the effort to achieve as perfect an application as possible.